The meeting video recording and slides are now posted at
https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Regards
Bill
On Wed, 8 Jan 2020 at 11:00, Anton Komlev via TF-M <
tf-m(a)lists.trustedfirmware.org> wrote:
> Hi All,
>
>
>
> Thanks, Ken and Edison for offering the topics for tomorrow’s Tech forum.
>
> The agenda (always open) starts from:
>
> 1. Secure Partition Runtime Library
> 2. PSA FF 1.0.0 alignment
>
>
>
> Best regards,
>
> Anton
>
>
>
> *From:* TF-M <tf-m-bounces(a)lists.trustedfirmware.org> * On Behalf Of *Edison
> Ai via TF-M
> *Sent:* 07 January 2020 08:19
> *To:* 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
> *Cc:* nd <nd(a)arm.com>
> *Subject:* Re: [TF-M] TF-M Technical Forum call - January 9
>
>
>
> Hi Anton,
>
>
>
> I will share something about the PSA FF 1.0.0 alignment. About 10 – 15
> minutes.
>
>
>
> Thanks,
>
> Edison
>
>
>
> *From:* TF-M <tf-m-bounces(a)lists.trustedfirmware.org> *On Behalf Of *Ken
> Liu via TF-M
> *Sent:* Tuesday, January 7, 2020 3:33 PM
> *To:* tf-m(a)lists.trustedfirmware.org
> *Cc:* nd <nd(a)arm.com>
> *Subject:* Re: [TF-M] TF-M Technical Forum call - January 9
>
>
>
> Hi Anton,
>
> I can share the status of Secure Partition Runtime Library in the tech
> forum.
>
>
>
> /Ken
>
>
>
> *From:* TF-M <tf-m-bounces(a)lists.trustedfirmware.org> *On Behalf Of *Anton
> Komlev via TF-M
> *Sent:* Tuesday, January 7, 2020 1:56 AM
> *To:* TF-M(a)lists.trustedfirmware.org
> *Cc:* nd <nd(a)arm.com>
> *Subject:* [TF-M] TF-M Technical Forum call - January 9
>
>
>
> Hello,
>
>
>
> Hope that the new year is truly happy for everybody.
>
> The next session of the Technical Forum is planned on the coming *Thursday,
> January 9th*.
>
> Regarding the time, I think that the last session was a good compromise to
> suit majority of the participants so propose to keep the time slot *at
> 7:00-8:00 UTC*.
>
> This time suits members in Europe and Asia, although participants from US
> (specially from the East coast) might have inconveniences.
>
> Reminding that the recorded sessions and materials are available on the
> web site: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
>
>
>
> Please reply to this email to post your topics for the agenda. Any
> questions, proposals, concerns are all valid points for our open discussion
> so do not hesitate to share it.
>
>
>
> Best regards,
>
> Anton Komlev
>
>
> --
> TF-M mailing list
> TF-M(a)lists.trustedfirmware.org
> https://lists.trustedfirmware.org/mailman/listinfo/tf-m
>
--
[image: Linaro] <http://www.linaro.org/>
*Bill Fletcher* | *Field Engineering*
T: +44 7833 498336 <+44+7833+498336>
bill.fletcher(a)linaro.org | Skype: billfletcher2020
Hi.
I am a bit confused on how would the following be addressed by a having a dedicated development branch. Would it be possible to elaborate please?
There is another way maybe help to solve this problem, we can define a merge policy like this: The patches cannot be merged to master branch if the patch is not based on the TOP HEAD.
1. If you have dev branches A and B, with common ancestry the HEAD_M , they both have been tested, and are merged with 2 minutes difference, then branch B will be based on A and will not have tested in that way, but will be present in master and assumed stable.
2. If you have dev branches A and B , and we decide as policy that B needs to constantly be based on A ( i.e the newest patch should be based on the last patch under review ). There will always be a still a small window that you can make a change in A, merge it, and B is not updated. Not to account for the significant overhead this will have to development.
3. If we adopt a generic dev branch and merge it to master overnight then this problem does not exist to begin with but the overall development flow will be delayed.
The TF-M Merge strategy has the following components:
* Master as the common development branch.
* Release Tags for stable releases, based on master
* Feature branches for development of big changes without affecting the flow of master
To my understanding the following assumptions apply:
* RC tags are always stable and extensively tested.
* Feature branches usually are based on RC tags, and re-based on top of master right before merging them.
* Master should be stable, but is not guaranteed to to.
* There is no mitigation for scenarios of having individually tested patches merged in a small window, introducing a bug when combined, or having a patch-chain merged, and some of the intermediate patches breaking master but the final patch passing tests.
* It is impossible to test everything all the time, while keeping the merge bandwidth at maximum. The CI will have to test a significant amount of platforms, but relies on the developer on having a look on weather his change may affect anything outside of this scope. Since with the current process flow, there is no roll-back strategy, or a merge windows, there is a significant time gain in the time that each patch is held back when in review. Then the assumption is that if it breaks something which has not been tested, the developer will have to commit some extra time to address it. If that trade-off is unacceptable it can easily be addressed with a policy change.
In community projects the most commonly accepted solution that seems to mitigate a scenario of patches A, B being merged in a small time delta, is using "merge windows". But before we adopt any new policy we should be evaluating our needs.
To that end would it be possible to go back to start and decide on the requirements? What are we trying to achieve? What are we trying to address? What would the acceptable cost in development time be?
Regards,
Minos
________________________________
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> on behalf of Edison Ai via TF-M <tf-m(a)lists.trustedfirmware.org>
Sent: 10 January 2020 07:40
To: 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi,
Let's continue to discuss this topic.
I agree with this, the CI is just a tool, we should not only rely on it.
Thanks Gyorgy to point out the quality policy, we need to think about them when we discuss the version control.
In the current status, there is only one master branch for most of the development work in TF-M. Of course, we can add a warning to say that the master is constantly changing, there may be some problems in building or test running, and let the user use the release tag. But it is not convenience and impossible if they are upstreaming patches. And even to TF-M developers, we had met several times of the master branch is broken.
There is another way maybe help to solve this problem, we can define a merge policy like this: The patches cannot be merged to master branch if the patch is not based on the TOP HEAD. But this is very difficult to follow because there may be several maintainers could and need to merged patches at the same time. They need to align with each other to confirm their patches are on the TOP. But now, we often meet this case, while one patch rebases to TOP and waiting for the CI result, another patch is merged into master. The patch needs to rebase again.
I do not want to give more examples here.
Of course, it is a big change to involve a new branch, there must be many documents that need to be updated, and some policies need to be changed. And even this needs someone to maintain the alignment with 2 branches. But I think it is more useful and helpful for all users.
Thanks,
Edison
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Gyorgy Szing via TF-M
Sent: Friday, December 13, 2019 10:01 PM
To: Minos Galanakis <Minos.Galanakis(a)arm.com>; Soby Mathew <Soby.Mathew(a)arm.com>; tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi,
Hi,
I agree, the CI shall not dictate how we use the version control system. It shall adapt.
Regarding your suggestions, I think the main problem is we are mixing stuff, this time quality with version control. Before we make decisions we shall understand where we are.
The current quality policy is that we only make releases for communication purposes. To give a clean interface for tf-m users and to allow planning their work. Releases allow them to execute their tf-m integration process less frequently. Only for each release or specific releases and not for each commit. The current quality policy identifies a single quality level only, and says any patch we publish is "golden quality", it matches the highest quality standard we can achieve (with sane constraints). Also to make our life easy we decided to use the master branch to hold these patches.
At the same time we use the master branch for development. Any change we make is made against master. This means each pull request and thus each review targets master. For review purposes the best is to have a chain of small modifications, otherwise the review content becomes too large to follow.
The TF-A "branching strategy" tries to address this issue by introducing an integration branch used for development. This allows master to be more release specific.
I suggest to take the following approach (details to be discussed):
- introduce more quality levels i.e.:
- none: content of a topic branch, or content pushed to review.
- bronze: content passed code review and patch specific testing.
- silver: content passed a more though daily testing.
- gold: a release. A pack of source-code, feature state document (release notes), reviewed documentation (user manual, reference manual), test evidence, documentation of test efforts to allow repeatability. The version control system can be used to store content, and to provide identification info (i.e. tagging), but most likely the release will need other kind of storage to be used (i.e. documentation).
- platina: reaching extra quality level trough passing PSA or some FUSA qualification. Or we may simply use extra release for this.
Naming the quality levels allows us to have a cleaner definition of what can be expected at a specific level (set of quality measures, i.e. static analysis, code review, test configuration). It would also allow us cleaner communication and to find how we use the version system for quality purposes.
I also expect this discussion to help defining how the version system is used for development purposes.
The current state works ok, but is a sort of naturally grown. We might have reached the point when more pragmatic approach may be needed.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Minos Galanakis via TF-M
Sent: 13 December 2019 12:23
To: Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>; Soby Mathew <Soby.Mathew(a)arm.com>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi all.
My personal comments on this.
I would like to point out that the CI is a tool, not the core project. I do not believe we should be changing our development strategy based on what the tool is doing. We should instead adjust the tool to fit our requirements.
* No patches should be/ are merged to master when CI fails. If master breaks it should most commonly be because of something we are not testing for. Using an integration branch would not change that.
* As a developer I find it more convoluted to work with projects who use different integration strategies. The most common assumption in open source projects is that you have a master branch which is the bleeding edge, but can contain untested bugs, and the release immutable git tags for versioning. Using branch merges as versioning is a design for the pull request model which is not quite compatible with Gerrit.
* Most of the CI downtime has nothing to do with the merge strategy, they are more of a chicken and the egg philosophical problem. If your patch or branch introduced a change which affects the tests outputs, how will you test it if the CI expects the old output? An integration branch would not solve the merge freeze periods, would just affect a different branch from master.
* I believe feature branches are quite useful, since changes to master do not disrupt the development flow of a big change, and even though they will require some maintenance to re-sync before the final patch , it will be handled by an engineer who knows the feature, and full understands the regression vectors.
If I were to suggest some changes for stability purposes, I would start smaller:
* Update documentation to instruct users to check out from release tags, warning then that master is constantly changing.
* Adjust the CI to detect an Allow-CI flag from every branch. That way developers can test any patch from any feature branch. The logic for that is already present in the code, but requires Gerrit to be configured accordingly.
* Add an undo process. This would be the only case for an integration branch. All patches are merged to a temporary branch, after confirming they have passed testing individually. On the once per day nightly test, the group of different patches, will be tested against an extensive job, in models and hardware, and only if successful it will fast forward master to that state.
Regards
Minos
________________________________
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> on behalf of Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>
Sent: 13 December 2019 08:55
To: Soby Mathew <Soby.Mathew(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Soby,
Thanks for your detail description.
> Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
> This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
I think it's a good method like this so that we can double confirm the "master" branch is stable.
And this also can fix one case even the CI can work normally: one patch is ready to merge, and it is not based on the latest HEAD, but there is no conflict. We can merge the patch directly and let gerrit do rebase by itself. But we cannot confirm the CI test can pass.
Any comment for this from others?
For multiple feature branches, I think we can stop to discuss about it now until we have some strong demands for it. It is indeed a big change for us now.
Thanks,
Edison
-----Original Message-----
From: Soby Mathew <Soby.Mathew(a)arm.com>
Sent: Friday, December 13, 2019 5:14 AM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
On 11/12/2019 09:05, Edison Ai (Arm Technology China) via TF-M wrote:
> Hi Gyorgy,
>
> Thanks to point it out. I agree with you that it will be better if we can align these two projects in this. I had a quick check the branches from TF-A: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/.
> There are three branches in TF-A:
> - "integration" branch, should be used for new features.
> - "master" branch, which is behind of "integration" branch. But I am nor sure what is the strategy to update it.
Hi Edison,
Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
> - "topics/epic_beta0_spmd", I thinks it should like a feature branch for big feature.
> @Soby Mathew Could you help to share more information about it? Thanks very much.
We usually do not have feature branches in TF-A. The topics/epic_beta0_spmd is a prototyping branch where we wanted to share code with collaborators outside TF-A. The patches on this branch are not visible in gerrit review and no patches in gerrit review will be merged to this branch. Once the prototyping is complete, then patches on this branch will be reworked and pushed to gerrit review and finally get merged to integration and this branch will be deleted.
Our experience have been, long running development branches are generally a maintenance overhead. Merging these development branches before a release may also be risky as some of the changes may have unknown interactions and may become difficult to resolve.
The "topic" in gerrit review is effectively a branch. For example, this
review:
https://review.trustedfirmware.org/#/q/topic:od/debugfs+(status:open+OR+sta…
is a set of patches on topic "od/debugfs" and can be treated as development branch. This branch is alive as long as patches are not merged.
We need to understand the motivations for the change. Broken CI is an argument but development branches will only exacerbate that problem since we don't know the stability of each of those branches. Also merge conflict will not reduce due to development branches. Its just delaying the merge conflict to a later point.
There may be other reasons, but generally it is better to merge sensible patches (+2ed) within a feature even before the feature is complete as it will reduce merge conflicts (we have to ensure testing/build coverage for the patch). These are my thoughts on this.
Best Regards
Soby Mathew
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I propose to implement PSA_Panic () as a macro (like the classic C assert feature) and not as a plain C function.
The benefit is that the macro allows you to insert also information like __FILE__ and __LINE__ which helps during the development phase of projects (i.e. when TF-M is incorrectly used by the non-secure side. __FILE__ and __LINE__ is useful also when no source code is available (at the debug stage) as it allows support to provide hints for the root cause of the issue.
You may have different variants of the PSA_Panic macro, i.e. a debug and release version.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Ken,
Today there are multiple different implementation of event logging used in the industry, but in a nutshell all use a similar concept.
You may start reading http://www.keil.com/pack/doc/compiler/EventRecorder/html/er_overview.html which is the implementation used currently in MDK. It uses a buffer that is read by the debugger. The buffer size is configurable and a faster debugger requires typically smaller buffer sizes. Also it introduces an XML file that describes the messages - and this description is used also by other tools like Percepio.
You may remap the annotation hooks also to classic printf.
So overall the concept gives you more flexibility and introducing it at a later stage into a project usually creates legacy effects.
For example we had in MDK middleware initially printf type annotations and introduced later events. As users are reluctant to change technology during the project lifecycle we end up to maintain both the old printf and the new event recorder annotations. This could have been avoided by using the right (flexible) concept from the beginning.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi,
Let's continue to discuss this topic.
I agree with this, the CI is just a tool, we should not only rely on it.
Thanks Gyorgy to point out the quality policy, we need to think about them when we discuss the version control.
In the current status, there is only one master branch for most of the development work in TF-M. Of course, we can add a warning to say that the master is constantly changing, there may be some problems in building or test running, and let the user use the release tag. But it is not convenience and impossible if they are upstreaming patches. And even to TF-M developers, we had met several times of the master branch is broken.
There is another way maybe help to solve this problem, we can define a merge policy like this: The patches cannot be merged to master branch if the patch is not based on the TOP HEAD. But this is very difficult to follow because there may be several maintainers could and need to merged patches at the same time. They need to align with each other to confirm their patches are on the TOP. But now, we often meet this case, while one patch rebases to TOP and waiting for the CI result, another patch is merged into master. The patch needs to rebase again.
I do not want to give more examples here.
Of course, it is a big change to involve a new branch, there must be many documents that need to be updated, and some policies need to be changed. And even this needs someone to maintain the alignment with 2 branches. But I think it is more useful and helpful for all users.
Thanks,
Edison
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Gyorgy Szing via TF-M
Sent: Friday, December 13, 2019 10:01 PM
To: Minos Galanakis <Minos.Galanakis(a)arm.com>; Soby Mathew <Soby.Mathew(a)arm.com>; tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi,
Hi,
I agree, the CI shall not dictate how we use the version control system. It shall adapt.
Regarding your suggestions, I think the main problem is we are mixing stuff, this time quality with version control. Before we make decisions we shall understand where we are.
The current quality policy is that we only make releases for communication purposes. To give a clean interface for tf-m users and to allow planning their work. Releases allow them to execute their tf-m integration process less frequently. Only for each release or specific releases and not for each commit. The current quality policy identifies a single quality level only, and says any patch we publish is "golden quality", it matches the highest quality standard we can achieve (with sane constraints). Also to make our life easy we decided to use the master branch to hold these patches.
At the same time we use the master branch for development. Any change we make is made against master. This means each pull request and thus each review targets master. For review purposes the best is to have a chain of small modifications, otherwise the review content becomes too large to follow.
The TF-A "branching strategy" tries to address this issue by introducing an integration branch used for development. This allows master to be more release specific.
I suggest to take the following approach (details to be discussed):
- introduce more quality levels i.e.:
- none: content of a topic branch, or content pushed to review.
- bronze: content passed code review and patch specific testing.
- silver: content passed a more though daily testing.
- gold: a release. A pack of source-code, feature state document (release notes), reviewed documentation (user manual, reference manual), test evidence, documentation of test efforts to allow repeatability. The version control system can be used to store content, and to provide identification info (i.e. tagging), but most likely the release will need other kind of storage to be used (i.e. documentation).
- platina: reaching extra quality level trough passing PSA or some FUSA qualification. Or we may simply use extra release for this.
Naming the quality levels allows us to have a cleaner definition of what can be expected at a specific level (set of quality measures, i.e. static analysis, code review, test configuration). It would also allow us cleaner communication and to find how we use the version system for quality purposes.
I also expect this discussion to help defining how the version system is used for development purposes.
The current state works ok, but is a sort of naturally grown. We might have reached the point when more pragmatic approach may be needed.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Minos Galanakis via TF-M
Sent: 13 December 2019 12:23
To: Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>; Soby Mathew <Soby.Mathew(a)arm.com>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi all.
My personal comments on this.
I would like to point out that the CI is a tool, not the core project. I do not believe we should be changing our development strategy based on what the tool is doing. We should instead adjust the tool to fit our requirements.
* No patches should be/ are merged to master when CI fails. If master breaks it should most commonly be because of something we are not testing for. Using an integration branch would not change that.
* As a developer I find it more convoluted to work with projects who use different integration strategies. The most common assumption in open source projects is that you have a master branch which is the bleeding edge, but can contain untested bugs, and the release immutable git tags for versioning. Using branch merges as versioning is a design for the pull request model which is not quite compatible with Gerrit.
* Most of the CI downtime has nothing to do with the merge strategy, they are more of a chicken and the egg philosophical problem. If your patch or branch introduced a change which affects the tests outputs, how will you test it if the CI expects the old output? An integration branch would not solve the merge freeze periods, would just affect a different branch from master.
* I believe feature branches are quite useful, since changes to master do not disrupt the development flow of a big change, and even though they will require some maintenance to re-sync before the final patch , it will be handled by an engineer who knows the feature, and full understands the regression vectors.
If I were to suggest some changes for stability purposes, I would start smaller:
* Update documentation to instruct users to check out from release tags, warning then that master is constantly changing.
* Adjust the CI to detect an Allow-CI flag from every branch. That way developers can test any patch from any feature branch. The logic for that is already present in the code, but requires Gerrit to be configured accordingly.
* Add an undo process. This would be the only case for an integration branch. All patches are merged to a temporary branch, after confirming they have passed testing individually. On the once per day nightly test, the group of different patches, will be tested against an extensive job, in models and hardware, and only if successful it will fast forward master to that state.
Regards
Minos
________________________________
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> on behalf of Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>
Sent: 13 December 2019 08:55
To: Soby Mathew <Soby.Mathew(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Soby,
Thanks for your detail description.
> Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
> This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
I think it's a good method like this so that we can double confirm the "master" branch is stable.
And this also can fix one case even the CI can work normally: one patch is ready to merge, and it is not based on the latest HEAD, but there is no conflict. We can merge the patch directly and let gerrit do rebase by itself. But we cannot confirm the CI test can pass.
Any comment for this from others?
For multiple feature branches, I think we can stop to discuss about it now until we have some strong demands for it. It is indeed a big change for us now.
Thanks,
Edison
-----Original Message-----
From: Soby Mathew <Soby.Mathew(a)arm.com>
Sent: Friday, December 13, 2019 5:14 AM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
On 11/12/2019 09:05, Edison Ai (Arm Technology China) via TF-M wrote:
> Hi Gyorgy,
>
> Thanks to point it out. I agree with you that it will be better if we can align these two projects in this. I had a quick check the branches from TF-A: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/.
> There are three branches in TF-A:
> - "integration" branch, should be used for new features.
> - "master" branch, which is behind of "integration" branch. But I am nor sure what is the strategy to update it.
Hi Edison,
Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
> - "topics/epic_beta0_spmd", I thinks it should like a feature branch for big feature.
> @Soby Mathew Could you help to share more information about it? Thanks very much.
We usually do not have feature branches in TF-A. The topics/epic_beta0_spmd is a prototyping branch where we wanted to share code with collaborators outside TF-A. The patches on this branch are not visible in gerrit review and no patches in gerrit review will be merged to this branch. Once the prototyping is complete, then patches on this branch will be reworked and pushed to gerrit review and finally get merged to integration and this branch will be deleted.
Our experience have been, long running development branches are generally a maintenance overhead. Merging these development branches before a release may also be risky as some of the changes may have unknown interactions and may become difficult to resolve.
The "topic" in gerrit review is effectively a branch. For example, this
review:
https://review.trustedfirmware.org/#/q/topic:od/debugfs+(status:open+OR+sta…
is a set of patches on topic "od/debugfs" and can be treated as development branch. This branch is alive as long as patches are not merged.
We need to understand the motivations for the change. Broken CI is an argument but development branches will only exacerbate that problem since we don't know the stability of each of those branches. Also merge conflict will not reduce due to development branches. Its just delaying the merge conflict to a later point.
There may be other reasons, but generally it is better to merge sensible patches (+2ed) within a feature even before the feature is complete as it will reduce merge conflicts (we have to ensure testing/build coverage for the patch). These are my thoughts on this.
Best Regards
Soby Mathew
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Hi Tamas,
IAR provides C libraries in various configurations, depending on
optimization levels, target types, needed features.
Normally the linker selects the appropriate libraries depending on
target, optimization, semihosting etc, but it can be told to not do
that, in case there is a need to provide non-standard libraries.
Cheers,
/Thomas
Den 2020-01-09 kl. 09:41, skrev Tamas Ban via TF-M:
>
> Hi Thomas,
>
> Just for my understanding:
>
> * Does IAR provide a C std. lib as part of IAR toolchain package?
> * How the std C lib linked to the image? Does user provide an
> explicit flag which std. C lib to linked to the image?
>
> Tamas
>
> *From:*TF-M <tf-m-bounces(a)lists.trustedfirmware.org> *On Behalf Of
> *Thomas Törnblom via TF-M
> *Sent:* 08 January 2020 12:45
> *To:* tf-m(a)lists.trustedfirmware.org
> *Subject:* Re: [TF-M] [Request For Comments] apply "-fno-builtin" as
> default compiler flags
>
> The IAR toolchain does not produce any special "builtin" calls and
> thus does not have any flag similar to "-fno-builtin".
>
> /Thomas
>
> Den 2020-01-08 kl. 03:53, skrev Ken Liu via TF-M:
>
> Hi,
>
> �
>
> As TF-M needs runtime APIs so we are creating the Secure Partition
> runtime library, code is ready but we have not forwarded all
> necessary runtime APIs to the version TF-M implemented, this was
> caused by the toolchain optimization for built-in APIs, such as:
>
> �
>
> - Forward printf(%s) to puts if there is only one string parameter.
>
> - ARMCLANG would forward memxxx API into an optimized variant.
>
> �
>
> With the '-fno-builtin' flags set in the toolchain, this
> optimization would be disabled so that user just implement the
> same name built-in to replace the toolchain version.
>
> �
>
> Please help to check these point before applying '-fno-builtin'
> and provide your feedback:
>
> �
>
> - Could toolchains out of ARMCLANG and GNUARM have a similar flag?
>
> - Would it affect your project setting and how does it affect?
>
> �
>
> Please help to feedback. I will keep this thread open for ~1 week
> and let's get a conclusion after this.
>
> �
>
> Thanks!
>
> �
>
> /Ken
>
>
>
> --
>
> *Thomas T�rnblom*, /Product Engineer/
> IAR Systems AB
> Box 23051, Strandbodgatan 1
> SE-750 23 Uppsala, SWEDEN
> Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
> E-mail: thomas.tornblom(a)iar.com
> <mailto:thomas.tornblom@iar.com>Website: www.iar.com <http://www.iar.com>
> Twitter: www.twitter.com/iarsystems <http://www.twitter.com/iarsystems>
>
> IMPORTANT NOTICE: The contents of this email and any attachments are
> confidential and may also be privileged. If you are not the intended
> recipient, please notify the sender immediately and do not disclose
> the contents to any other person, use it for any purpose, or store or
> copy the information in any medium. Thank you. IMPORTANT NOTICE: The
> contents of this email and any attachments are confidential and may
> also be privileged. If you are not the intended recipient, please
> notify the sender immediately and do not disclose the contents to any
> other person, use it for any purpose, or store or copy the information
> in any medium. Thank you.
>
--
*Thomas Törnblom*, /Product Engineer/
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
E-mail: thomas.tornblom(a)iar.com <mailto:thomas.tornblom@iar.com>
Website: www.iar.com <http://www.iar.com>
Twitter: www.twitter.com/iarsystems <http://www.twitter.com/iarsystems>
Dear All,
The next session of the Technical Forum is planned in 2 weeks, Thursday, January 23rd at 7:00-8:00 UTC.
Please treat this email and an early invitation for agenda topic collection. Any questions, proposals, concerns are all valid points for our open discussion so do not hesitate to share it.
A big or complicated topics are worth to preliminary discussed over a mailing list.
Best regards,
Anton Komlev
Hi,
I assume the main purpose of isolation would be protect the code been seen by the AppRoT. Let's check with the FF author for detailed answers.
The building instructions now is just create separate libraries and finally combine them together - since vendors can create Secure Partitions, these modularized building can't be avoided.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: Thursday, January 9, 2020 4:00 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] Code Protection between secure services
I suggest we review the requirement of code isolation on the secure side.
R/W data and R/O data should definitely be isolated, but code isolation has implications:
* Code cannot be share between services (i.e. no linker optimization to reduce memory footprint)
* Sharing library code
* Overall the build instructions of the system are more complicated
* Adding device specific driver code (i.e. to crypto) can become tricky
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi Thomas,
Just for my understanding:
* Does IAR provide a C std. lib as part of IAR toolchain package?
* How the std C lib linked to the image? Does user provide an explicit flag which std. C lib to linked to the image?
Tamas
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Thomas Törnblom via TF-M
Sent: 08 January 2020 12:45
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] [Request For Comments] apply "-fno-builtin" as default compiler flags
The IAR toolchain does not produce any special "builtin" calls and thus does not have any flag similar to "-fno-builtin".
/Thomas
Den 2020-01-08 kl. 03:53, skrev Ken Liu via TF-M:
Hi,
�
As TF-M needs runtime APIs so we are creating the Secure Partition runtime library, code is ready but we have not forwarded all necessary runtime APIs to the version TF-M implemented, this was caused by the toolchain optimization for built-in APIs, such as:
�
- Forward printf(%s) to puts if there is only one string parameter.
- ARMCLANG would forward memxxx API into an optimized variant.
�
With the '-fno-builtin' flags set in the toolchain, this optimization would be disabled so that user just implement the same name built-in to replace the toolchain version.
�
Please help to check these point before applying '-fno-builtin' and provide your feedback:
�
- Could toolchains out of ARMCLANG and GNUARM have a similar flag?
- Would it affect your project setting and how does it affect?
�
Please help to feedback. I will keep this thread open for ~1 week and let's get a conclusion after this.
�
Thanks!
�
/Ken
--
Thomas T�rnblom, Product Engineer
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
E-mail: thomas.tornblom(a)iar.com<mailto:thomas.tornblom@iar.com> Website: www.iar.com<http://www.iar.com>
Twitter: www.twitter.com/iarsystems<http://www.twitter.com/iarsystems>
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi,
We have a prototype audit logging service and one of the purposes is to provide the event logging.
The reason we keep printf first is that it is so direct and some projects reference it, for example, booting or services. Eventually, we need can investigate the possibility of forwarding all printf into event logging.
One question is that there needs to be a buffer for collecting the events so it has limited capacity?
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: Thursday, January 9, 2020 3:42 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] The logging mechanism change in TF-M
I recommend instead of using printf with plain text strings, to change the concept to event annotations.
This is already implemented in several RTOS systems (i.e. FreeRTOS or RTX).
Event annotations give you more flexibility:
* can be mapped to memory buffer, printf output, or analysers like Event Recorder in MDK or Percepio
* annotations are described in XML file using event groups. Can be mapped to test automation systems and reduce overhead
* no direct mapping to a peripheral. UART may be not available on all systems.
* overall less overhead in the system (as printf is expensive). Can remain in production code when it just goes to memory buffer
Let me know if you want to have further pointers or information.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
I suggest we review the requirement of code isolation on the secure side.
R/W data and R/O data should definitely be isolated, but code isolation has implications:
* Code cannot be share between services (i.e. no linker optimization to reduce memory footprint)
* Sharing library code
* Overall the build instructions of the system are more complicated
* Adding device specific driver code (i.e. to crypto) can become tricky
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
I recommend instead of using printf with plain text strings, to change the concept to event annotations.
This is already implemented in several RTOS systems (i.e. FreeRTOS or RTX).
Event annotations give you more flexibility:
* can be mapped to memory buffer, printf output, or analysers like Event Recorder in MDK or Percepio
* annotations are described in XML file using event groups. Can be mapped to test automation systems and reduce overhead
* no direct mapping to a peripheral. UART may be not available on all systems.
* overall less overhead in the system (as printf is expensive). Can remain in production code when it just goes to memory buffer
Let me know if you want to have further pointers or information.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you. IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Got 3 feedbacks till now all reports no problem. I am going to merge this one before end of today.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: Monday, January 6, 2020 1:56 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] [Call for cygwin volunteers] Remove the mbed-crypto building workaround
Thanks for the feedback, let me take a note.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of Qixiang Xu via TF-M
Sent: Monday, January 6, 2020 1:49 PM
To: tf-m(a)lists.trustedfirmware.org<mailto:tf-m@lists.trustedfirmware.org>
Subject: Re: [TF-M] [Call for cygwin volunteers] Remove the mbed-crypto building workaround
Ken,
I have cherry picked the patch and tested it on Cygwin:
$ cmake --version
cmake version 3.11.1
CMake suite maintained and supported by Kitware (kitware.com/cmake).
The patch works and no issue found.
Best Regards,
Qixiang Xu
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of Ken Liu via TF-M
Sent: Monday, January 6, 2020 11:00 AM
To: tf-m(a)lists.trustedfirmware.org<mailto:tf-m@lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com<mailto:nd@arm.com>>
Subject: [TF-M] [Call for cygwin volunteers] Remove the mbed-crypto building workaround
Hi,
I create a patch for removing the workaround for mbed-crypto building:
https://review.trustedfirmware.org/c/trusted-firmware-m/+/3022
We tried on cmake 3.7 and 3.10 with cygwin and it works; can some Cygwin/mingw user pick this patch and test if it could work in your side?
Thanks for your contribution 😊
/Ken
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Thanks Thomas, then IAR won't be a difficult part for this.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Thomas Törnblom via TF-M
Sent: Wednesday, January 8, 2020 7:45 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] [Request For Comments] apply "-fno-builtin" as default compiler flags
The IAR toolchain does not produce any special "builtin" calls and thus does not have any flag similar to "-fno-builtin".
/Thomas
Den 2020-01-08 kl. 03:53, skrev Ken Liu via TF-M:
Hi,
�
As TF-M needs runtime APIs so we are creating the Secure Partition runtime library, code is ready but we have not forwarded all necessary runtime APIs to the version TF-M implemented, this was caused by the toolchain optimization for built-in APIs, such as:
�
- Forward printf(%s) to puts if there is only one string parameter.
- ARMCLANG would forward memxxx API into an optimized variant.
�
With the '-fno-builtin' flags set in the toolchain, this optimization would be disabled so that user just implement the same name built-in to replace the toolchain version.
�
Please help to check these point before applying '-fno-builtin' and provide your feedback:
�
- Could toolchains out of ARMCLANG and GNUARM have a similar flag?
- Would it affect your project setting and how does it affect?
�
Please help to feedback. I will keep this thread open for ~1 week and let's get a conclusion after this.
�
Thanks!
�
/Ken
--
Thomas T�rnblom, Product Engineer
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
E-mail: thomas.tornblom(a)iar.com<mailto:thomas.tornblom@iar.com> Website: www.iar.com<http://www.iar.com>
Twitter: www.twitter.com/iarsystems<http://www.twitter.com/iarsystems>
The IAR toolchain does not produce any special "builtin" calls and thus
does not have any flag similar to "-fno-builtin".
/Thomas
Den 2020-01-08 kl. 03:53, skrev Ken Liu via TF-M:
>
> Hi,
>
> As TF-M needs runtime APIs so we are creating the Secure Partition
> runtime library, code is ready but we have not forwarded all necessary
> runtime APIs to the version TF-M implemented, this was caused by the
> toolchain optimization for built-in APIs, such as:
>
> - Forward printf(%s) to puts if there is only one string parameter.
>
> - ARMCLANG would forward memxxx API into an optimized variant.
>
> With the '-fno-builtin' flags set in the toolchain, this optimization
> would be disabled so that user just implement the same name built-in
> to replace the toolchain version.
>
> Please help to check these point before applying '-fno-builtin' and
> provide your feedback:
>
> - Could toolchains out of ARMCLANG and GNUARM have a similar flag?
>
> - Would it affect your project setting and how does it affect?
>
> Please help to feedback. I will keep this thread open for ~1 week and
> let's get a conclusion after this.
>
> Thanks!
>
> /Ken
>
>
--
*Thomas Törnblom*, /Product Engineer/
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
E-mail: thomas.tornblom(a)iar.com <mailto:thomas.tornblom@iar.com>
Website: www.iar.com <http://www.iar.com>
Twitter: www.twitter.com/iarsystems <http://www.twitter.com/iarsystems>
Hi All,
Thanks, Ken and Edison for offering the topics for tomorrow's Tech forum.
The agenda (always open) starts from:
1. Secure Partition Runtime Library
2. PSA FF 1.0.0 alignment
Best regards,
Anton
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai via TF-M
Sent: 07 January 2020 08:19
To: 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] TF-M Technical Forum call - January 9
Hi Anton,
I will share something about the PSA FF 1.0.0 alignment. About 10 - 15 minutes.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of Ken Liu via TF-M
Sent: Tuesday, January 7, 2020 3:33 PM
To: tf-m(a)lists.trustedfirmware.org<mailto:tf-m@lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com<mailto:nd@arm.com>>
Subject: Re: [TF-M] TF-M Technical Forum call - January 9
Hi Anton,
I can share the status of Secure Partition Runtime Library in the tech forum.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of Anton Komlev via TF-M
Sent: Tuesday, January 7, 2020 1:56 AM
To: TF-M(a)lists.trustedfirmware.org<mailto:TF-M@lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com<mailto:nd@arm.com>>
Subject: [TF-M] TF-M Technical Forum call - January 9
Hello,
Hope that the new year is truly happy for everybody.
The next session of the Technical Forum is planned on the coming Thursday, January 9th.
Regarding the time, I think that the last session was a good compromise to suit majority of the participants so propose to keep the time slot at 7:00-8:00 UTC.
This time suits members in Europe and Asia, although participants from US (specially from the East coast) might have inconveniences.
Reminding that the recorded sessions and materials are available on the web site: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Please reply to this email to post your topics for the agenda. Any questions, proposals, concerns are all valid points for our open discussion so do not hesitate to share it.
Best regards,
Anton Komlev
Hi,
As TF-M needs runtime APIs so we are creating the Secure Partition runtime library, code is ready but we have not forwarded all necessary runtime APIs to the version TF-M implemented, this was caused by the toolchain optimization for built-in APIs, such as:
- Forward printf(%s) to puts if there is only one string parameter.
- ARMCLANG would forward memxxx API into an optimized variant.
With the '-fno-builtin' flags set in the toolchain, this optimization would be disabled so that user just implement the same name built-in to replace the toolchain version.
Please help to check these point before applying '-fno-builtin' and provide your feedback:
- Could toolchains out of ARMCLANG and GNUARM have a similar flag?
- Would it affect your project setting and how does it affect?
Please help to feedback. I will keep this thread open for ~1 week and let's get a conclusion after this.
Thanks!
/Ken
On 07/01/2020 01:23, Ken Liu via TF-M wrote:
> Hi Soby,
>
> Thanks for providing the reference - we have investigated the version in TF-A earlier, the difference part is we are facing the problem about how to flush the formatted data into device - TF-A has full control to the device so it could just output_char() but the secure partition cannot do this due to some driver sharing consideration. We can reference the TF-A implementation after the logging device mechanism is settled down.
>
> One question, the ARM Complier built-in would change printf to puts or some other variants in RVCT like __2printf, I searched TF-A sources found there is no '--fbulit-in' or 'no_scanlib' flags for the compiler but looks like TF-A has not met the scenarios TF-M met? Or...the runtime library mechanism for A and M are different?
>
> /Ken
Hi Ken,
The TF-A uses -fno-builtin compiler flag. Hence it doesn't face this
problem. If the goal is to not to pull in compiler builtin libraries,
setting this flag would be the right approach. The TF-M source tree
would need to provide libc.
Best Regards
Soby Mathew
Hi Anton,
I will share something about the PSA FF 1.0.0 alignment. About 10 - 15 minutes.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: Tuesday, January 7, 2020 3:33 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] TF-M Technical Forum call - January 9
Hi Anton,
I can share the status of Secure Partition Runtime Library in the tech forum.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of Anton Komlev via TF-M
Sent: Tuesday, January 7, 2020 1:56 AM
To: TF-M(a)lists.trustedfirmware.org<mailto:TF-M@lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com<mailto:nd@arm.com>>
Subject: [TF-M] TF-M Technical Forum call - January 9
Hello,
Hope that the new year is truly happy for everybody.
The next session of the Technical Forum is planned on the coming Thursday, January 9th.
Regarding the time, I think that the last session was a good compromise to suit majority of the participants so propose to keep the time slot at 7:00-8:00 UTC.
This time suits members in Europe and Asia, although participants from US (specially from the East coast) might have inconveniences.
Reminding that the recorded sessions and materials are available on the web site: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Please reply to this email to post your topics for the agenda. Any questions, proposals, concerns are all valid points for our open discussion so do not hesitate to share it.
Best regards,
Anton Komlev
Hi Anton,
I can share the status of Secure Partition Runtime Library in the tech forum.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Anton Komlev via TF-M
Sent: Tuesday, January 7, 2020 1:56 AM
To: TF-M(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] TF-M Technical Forum call - January 9
Hello,
Hope that the new year is truly happy for everybody.
The next session of the Technical Forum is planned on the coming Thursday, January 9th.
Regarding the time, I think that the last session was a good compromise to suit majority of the participants so propose to keep the time slot at 7:00-8:00 UTC.
This time suits members in Europe and Asia, although participants from US (specially from the East coast) might have inconveniences.
Reminding that the recorded sessions and materials are available on the web site: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Please reply to this email to post your topics for the agenda. Any questions, proposals, concerns are all valid points for our open discussion so do not hesitate to share it.
Best regards,
Anton Komlev
Hi Soby,
Thanks for providing the reference - we have investigated the version in TF-A earlier, the difference part is we are facing the problem about how to flush the formatted data into device - TF-A has full control to the device so it could just output_char() but the secure partition cannot do this due to some driver sharing consideration. We can reference the TF-A implementation after the logging device mechanism is settled down.
One question, the ARM Complier built-in would change printf to puts or some other variants in RVCT like __2printf, I searched TF-A sources found there is no '--fbulit-in' or 'no_scanlib' flags for the compiler but looks like TF-A has not met the scenarios TF-M met? Or...the runtime library mechanism for A and M are different?
/Ken
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Soby Mathew via TF-M
Sent: Monday, January 6, 2020 9:35 PM
To: Anton Komlev <Anton.Komlev(a)arm.com>; TF-M(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] The logging mechanism change in TF-M
On 06/01/2020 11:45, Anton Komlev via TF-M wrote:
> Hi Ken, All,
>
> I like your approach of providing a minimalistic version of printf()
> for the logging purpose only.
>
> This would benefit to code size and performance while rich print
> formatting has no practical needs in this project.
>
> Best regards,
>
> Anton
>
> *From:* TF-M <tf-m-bounces(a)lists.trustedfirmware.org> *On Behalf Of
> *Ken Liu via TF-M
> *Sent:* 27 December 2019 03:38
> *To:* tf-m(a)lists.trustedfirmware.org
> *Cc:* nd <nd(a)arm.com>
> *Subject:* [TF-M] The logging mechanism change in TF-M
>
> Hi,
>
> We met some issues while implementing logging APIs like printf:
>
> * The build-in symbol optimization references other toolchain provided
> symbols into image (like change ‘printf’ to ‘puts’ or ‘xxxprintf’),
> this would happen in both we are implementing your ‘printf’ and
> referencing toolchain ‘printf’. Use a -fno-builtin would suppress
> this but this needs a compiler flag requirement for developers.
> * If we don’t provide necessary symbol but somewhere in program
> referenced it, ARMCLANG would provide one for us which contains the
> semihosting things, this increases the code size and cause trouble
> while the device is not running under semihosting env.
> * Also there are CMSIS user reports that __stdout would affect
> multiple thread object initialization. (No detail about the root
> cause, anyone could help provide something?)
>
> So it would be better that we remove the reference to toolchain stdout
> APIs, this could simplify the logging implementation since firmware
> logging MAY not need rich format (Comments?). A customized printf-like
> API is provided for logging but not being named as ‘printf’ directly.
>
> Due to the default logging device (UART) driver may be implemented for
> threads only, the logging functionality in exceptions is going to be
> suppressed for a while until we figure out how the logging in
> exceptions can be – there is a trade-off between security
> consideration (isolation) and performance (Routing the logging API to somewhere costs).
>
> Please provide your thinking, or what kind of logging API you are using.
>
> Thanks
>
> /Ken
>
The TF-A code base provides a reduced printf() functionality due to similar concerns and to reduce stack/memory usage
https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/lib/libc/p…
Also be aware that mbedTLS requires snprintf() so if printf() is being custom implemented, then it makes sense to do the same to snprintf() as well.
Best Regards
Soby Mathew
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timeslot is challenging. We hope it's not too difficult for anyone - we can
review after the first couple of meetings.Initially we propose a bi-weekly
call and then we'll change cadence depending on interest Feel free to
forward it to colleagues.──────────Bill Fletcher is inviting you to a
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Hello,
Hope that the new year is truly happy for everybody.
The next session of the Technical Forum is planned on the coming Thursday, January 9th.
Regarding the time, I think that the last session was a good compromise to suit majority of the participants so propose to keep the time slot at 7:00-8:00 UTC.
This time suits members in Europe and Asia, although participants from US (specially from the East coast) might have inconveniences.
Reminding that the recorded sessions and materials are available on the web site: https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Please reply to this email to post your topics for the agenda. Any questions, proposals, concerns are all valid points for our open discussion so do not hesitate to share it.
Best regards,
Anton Komlev
> Just a question: For Isolation Level 1, the hardware features of v8-M should be sufficient to implement interrupts natively. Is this correct understanding or did I miss anything?
This is essentially correct. As this is outside of the PSA-FF at present, TF-M would need to design and document how to integrate such IRQ handlers with its interrupt management framework, and how the interrupt handler can interact with the secure service code. For example, this might be achieved by resuming a SFC call that is waiting for a hardware operation to complete or delivering a signal to an IPC mode Secure Partition.
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
On 06/01/2020 11:45, Anton Komlev via TF-M wrote:
> Hi Ken, All,
>
> I like your approach of providing a minimalistic version of printf() for
> the logging purpose only.
>
> This would benefit to code size and performance while rich print
> formatting has no practical needs in this project.
>
> Best regards,
>
> Anton
>
> *From:* TF-M <tf-m-bounces(a)lists.trustedfirmware.org> *On Behalf Of *Ken
> Liu via TF-M
> *Sent:* 27 December 2019 03:38
> *To:* tf-m(a)lists.trustedfirmware.org
> *Cc:* nd <nd(a)arm.com>
> *Subject:* [TF-M] The logging mechanism change in TF-M
>
> Hi,
>
> We met some issues while implementing logging APIs like printf:
>
> * The build-in symbol optimization references other toolchain provided
> symbols into image (like change ‘printf’ to ‘puts’ or ‘xxxprintf’),
> this would happen in both we are implementing your ‘printf’ and
> referencing toolchain ‘printf’. Use a -fno-builtin would suppress
> this but this needs a compiler flag requirement for developers.
> * If we don’t provide necessary symbol but somewhere in program
> referenced it, ARMCLANG would provide one for us which contains the
> semihosting things, this increases the code size and cause trouble
> while the device is not running under semihosting env.
> * Also there are CMSIS user reports that __stdout would affect
> multiple thread object initialization. (No detail about the root
> cause, anyone could help provide something?)
>
> So it would be better that we remove the reference to toolchain stdout
> APIs, this could simplify the logging implementation since firmware
> logging MAY not need rich format (Comments?). A customized printf-like
> API is provided for logging but not being named as ‘printf’ directly.
>
> Due to the default logging device (UART) driver may be implemented for
> threads only, the logging functionality in exceptions is going to be
> suppressed for a while until we figure out how the logging in exceptions
> can be – there is a trade-off between security consideration (isolation)
> and performance (Routing the logging API to somewhere costs).
>
> Please provide your thinking, or what kind of logging API you are using.
>
> Thanks
>
> /Ken
>
The TF-A code base provides a reduced printf() functionality due to
similar concerns and to reduce stack/memory usage
https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/lib/libc/p…
Also be aware that mbedTLS requires snprintf() so if printf() is being
custom implemented, then it makes sense to do the same to snprintf() as
well.
Best Regards
Soby Mathew
Hi Ken, All,
I like your approach of providing a minimalistic version of printf() for the logging purpose only.
This would benefit to code size and performance while rich print formatting has no practical needs in this project.
Best regards,
Anton
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: 27 December 2019 03:38
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] The logging mechanism change in TF-M
Hi,
We met some issues while implementing logging APIs like printf:
* The build-in symbol optimization references other toolchain provided symbols into image (like change 'printf' to 'puts' or 'xxxprintf'), this would happen in both we are implementing your 'printf' and referencing toolchain 'printf'. Use a -fno-builtin would suppress this but this needs a compiler flag requirement for developers.
* If we don't provide necessary symbol but somewhere in program referenced it, ARMCLANG would provide one for us which contains the semihosting things, this increases the code size and cause trouble while the device is not running under semihosting env.
* Also there are CMSIS user reports that __stdout would affect multiple thread object initialization. (No detail about the root cause, anyone could help provide something?)
So it would be better that we remove the reference to toolchain stdout APIs, this could simplify the logging implementation since firmware logging MAY not need rich format (Comments?). A customized printf-like API is provided for logging but not being named as 'printf' directly.
Due to the default logging device (UART) driver may be implemented for threads only, the logging functionality in exceptions is going to be suppressed for a while until we figure out how the logging in exceptions can be - there is a trade-off between security consideration (isolation) and performance (Routing the logging API to somewhere costs).
Please provide your thinking, or what kind of logging API you are using.
Thanks
/Ken
This patch will add a new system reset function for SPM without using the existing platform_hal_system_reset(). The basic thinking is to create a dedicated HAL function for SPM to split with services, and not affect the secure partition work.
I am not sure if this will bring some problems or any potential risk for platform porting.
Please give feedback about this in this mail thread.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai via TF-M
Sent: Monday, December 30, 2019 3:43 PM
To: 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: [TF-M] System reset SPM HAL function
Hi All,
To align with PSA FF 1.0.0, the SPM needs to restart the entire system when some programmer error or panics are detected. So I had upstream a patch to add a system reset HAL function for SPM: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2780/.
The basic idea is to add a weak common function so that the platform can use this weak function to do reset. Please note, the platform needs to add its own implementation if there is any different.
Unfortunately, there is no such test to test the system reset function curreetly. So please call psa_panic() in secure services for simple testing based on the top of this link: https://review.trustedfirmware.org/#/q/topic:tfm_panic+(status:open+OR+stat….
You can send mail or add comments directly in patches if you have any questions or comments.
Thanks,
Edison
Hi,
After couples of patches get merged, the Secure Partition runtime library prototype is available. The purpose of this library (aka SPRTL) is to provide a place for shared functions between secure partitions under isolation level 2/3 which could avoid duplicated code symbols in Secure Partitions. The situation is:
- There is a folder for SPE dedicated function implementation: 'secure_fw/lib/sprt'. More APIs can be put in SPRTL by modifying the makefiles under this folder.
- Keep using toolchain provided 'memset/memcpy' due to inherit them is a bit complicated (of course these toolchain symbols are put in the shared region to avoid duplication). And we keep the customized candidate in source code for further investigation to see if we need this customized version or the default version.
- Overriding toolchain 'memcmp' into a customized version to show security consideration.
- Implemented a customized 'tfm_log_printf' to replace 'printf', which could avoid involving complicated STDIO mechanism into the code base.
- PSA FF APIs are now in it.
These changes are now working under the code base, some other functions are not available yet and to be done later due to no actual requirement for them, such as:
- Heap APIs, now crypto uses its own implemented heap while other services do not need them.
- RoT Service APIs, would request service owner to move the existing RoT Service APIs into SPRTL (should be just some function attribute change, let's check it).
Any feedbacks or issue reporting is welcome, please reply in the mailing list or create an issue at developer.trustedfirmware.org and assign to 'KenLSoft'.
BR and thanks.
/Ken
Thanks for the feedback, let me take a note.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Qixiang Xu via TF-M
Sent: Monday, January 6, 2020 1:49 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] [Call for cygwin volunteers] Remove the mbed-crypto building workaround
Ken,
I have cherry picked the patch and tested it on Cygwin:
$ cmake --version
cmake version 3.11.1
CMake suite maintained and supported by Kitware (kitware.com/cmake).
The patch works and no issue found.
Best Regards,
Qixiang Xu
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of Ken Liu via TF-M
Sent: Monday, January 6, 2020 11:00 AM
To: tf-m(a)lists.trustedfirmware.org<mailto:tf-m@lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com<mailto:nd@arm.com>>
Subject: [TF-M] [Call for cygwin volunteers] Remove the mbed-crypto building workaround
Hi,
I create a patch for removing the workaround for mbed-crypto building:
https://review.trustedfirmware.org/c/trusted-firmware-m/+/3022
We tried on cmake 3.7 and 3.10 with cygwin and it works; can some Cygwin/mingw user pick this patch and test if it could work in your side?
Thanks for your contribution 😊
/Ken
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Ken,
I have cherry picked the patch and tested it on Cygwin:
$ cmake --version
cmake version 3.11.1
CMake suite maintained and supported by Kitware (kitware.com/cmake).
The patch works and no issue found.
Best Regards,
Qixiang Xu
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: Monday, January 6, 2020 11:00 AM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] [Call for cygwin volunteers] Remove the mbed-crypto building workaround
Hi,
I create a patch for removing the workaround for mbed-crypto building:
https://review.trustedfirmware.org/c/trusted-firmware-m/+/3022
We tried on cmake 3.7 and 3.10 with cygwin and it works; can some Cygwin/mingw user pick this patch and test if it could work in your side?
Thanks for your contribution 😊
/Ken
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi,
I create a patch for removing the workaround for mbed-crypto building:
https://review.trustedfirmware.org/c/trusted-firmware-m/+/3022
We tried on cmake 3.7 and 3.10 with cygwin and it works; can some Cygwin/mingw user pick this patch and test if it could work in your side?
Thanks for your contribution 😊
/Ken
Hi Andrew,
Thanks for the reply and the confirmation of the flexibility of the PSA-FF
Just a question: For Isolation Level 1, the hardware features of v8-M should be sufficient to implement interrupts natively. Is this correct understanding or did I miss anything?
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi TF-Mers,
Happy new year!
Till now, the core has evolved much and keep evolving. Let's take a breath before we go further, some updates are on the table and wait for comments. Most of the core changes will not affect the usage, but there do have interface related parts needs to be mentioned. Here are the overall topics for comments:
- SPM/core sources renaming and changes, I think this part won't affect user much except those who copied sources into your own project and do the integration.
- The HAL design is on the way, this part do affect the existing platform integration, please take apart in the discussions for this topic (The design would come first).
- Some interface sources changing. Those PSA APIs won't be changed, but the folder name and place may be updated so you may need to change your project setting.
We also got some new features, the design would go first and they would be merged after the update is done (Ideally ;)). Such as interrupt logic/test publish.
These changes are trying to make the platform integration easier, so your feedback is important before these changes take place. And, it also makes the contribution to core logic easier. If you find something is missing, feel free to propose it here and we can discuss how much we could cover.
The detailed topics would be sent one by one (avoid makes everyone too busy).
Please put comments ;)
Thanks
/Ken
Almost miss the link 😉
https://review.trustedfirmware.org/c/trusted-firmware-m/+/2964
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: Monday, December 30, 2019 6:45 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Initialize IPC SPM in handler mode
Hi,
The existing SPM initialization is done in thread mode with PSP, because library model needs to enumerate the partition initialization function in thread mode. And IPC SPM re-uses the code so it is get initialized in this mode, too.
For IPC SPM, it needs to initial thread context and push the initial EXC_RETURN context in each thread’s stack, and the veneer thread (which belongs to non-secure partition instance) re-uses the stack of initial thread mode. This may cause problem since SPM is manipulating the stack it is now standing on. It does not cause problem now is because SPM initialization is working at the low end of stack pointer while the thread context is written at high end stack bottom, and SPM initialization would not return to thread, it just enters PendSV and then go away.
So SPM must work under MSP to avoid touching his standing place – and, the used part of initial thread stack needs to be clean up, for security issues. Now we can’t find a better way to clean both the used PSP stack and the MSP stack, unless we clear the PSP manually while working with MSP, and do a EXC_RETURN from handler mode to reset the MSP stack usage by hardware.
The patches is on the way for this purpose – and follows the patches of jumping to ns without cmse call – cmse call consumes secure stack during the calling while we want a known stack position to identify the caller frames in handler mode.
Patches would come later (I am testing if it could on different platforms).
Thanks.
/Ken
Hi,
The existing SPM initialization is done in thread mode with PSP, because library model needs to enumerate the partition initialization function in thread mode. And IPC SPM re-uses the code so it is get initialized in this mode, too.
For IPC SPM, it needs to initial thread context and push the initial EXC_RETURN context in each thread's stack, and the veneer thread (which belongs to non-secure partition instance) re-uses the stack of initial thread mode. This may cause problem since SPM is manipulating the stack it is now standing on. It does not cause problem now is because SPM initialization is working at the low end of stack pointer while the thread context is written at high end stack bottom, and SPM initialization would not return to thread, it just enters PendSV and then go away.
So SPM must work under MSP to avoid touching his standing place - and, the used part of initial thread stack needs to be clean up, for security issues. Now we can't find a better way to clean both the used PSP stack and the MSP stack, unless we clear the PSP manually while working with MSP, and do a EXC_RETURN from handler mode to reset the MSP stack usage by hardware.
The patches is on the way for this purpose - and follows the patches of jumping to ns without cmse call - cmse call consumes secure stack during the calling while we want a known stack position to identify the caller frames in handler mode.
Patches would come later (I am testing if it could on different platforms).
Thanks.
/Ken
Hi All,
To align with PSA FF 1.0.0, the SPM needs to restart the entire system when some programmer error or panics are detected. So I had upstream a patch to add a system reset HAL function for SPM: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2780/.
The basic idea is to add a weak common function so that the platform can use this weak function to do reset. Please note, the platform needs to add its own implementation if there is any different.
Unfortunately, there is no such test to test the system reset function curreetly. So please call psa_panic() in secure services for simple testing based on the top of this link: https://review.trustedfirmware.org/#/q/topic:tfm_panic+(status:open+OR+stat….
You can send mail or add comments directly in patches if you have any questions or comments.
Thanks,
Edison
Hi,
We met some issues while implementing logging APIs like printf:
* The build-in symbol optimization references other toolchain provided symbols into image (like change 'printf' to 'puts' or 'xxxprintf'), this would happen in both we are implementing your 'printf' and referencing toolchain 'printf'. Use a -fno-builtin would suppress this but this needs a compiler flag requirement for developers.
* If we don't provide necessary symbol but somewhere in program referenced it, ARMCLANG would provide one for us which contains the semihosting things, this increases the code size and cause trouble while the device is not running under semihosting env.
* Also there are CMSIS user reports that __stdout would affect multiple thread object initialization. (No detail about the root cause, anyone could help provide something?)
So it would be better that we remove the reference to toolchain stdout APIs, this could simplify the logging implementation since firmware logging MAY not need rich format (Comments?). A customized printf-like API is provided for logging but not being named as 'printf' directly.
Due to the default logging device (UART) driver may be implemented for threads only, the logging functionality in exceptions is going to be suppressed for a while until we figure out how the logging in exceptions can be - there is a trade-off between security consideration (isolation) and performance (Routing the logging API to somewhere costs).
Please provide your thinking, or what kind of logging API you are using.
Thanks
/Ken
Hi,
I want to arise this topic again - some patches are blocked due to feature implementation but I think now it is a good chance since staging tag has been done.
Will notify you with the patches - don't worry, it is just about some file rename in core/spm folder so if your patch does not rely on these folders a simple rebase should work for your patch.
/Ken
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu (Arm Technology China) via TF-M
Sent: Thursday, August 29, 2019 4:49 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] [RFC] Code restructure of core/spm
Two more patches added under this topic:
https://review.trustedfirmware.org/c/trusted-firmware-m/+/1836https://review.trustedfirmware.org/c/trusted-firmware-m/+/1837
BR
/Ken
> -----Original Message-----
> From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken
> Liu (Arm Technology China) via TF-M
> Sent: Thursday, August 15, 2019 3:15 PM
> To: tf-m(a)lists.trustedfirmware.org
> Cc: nd <nd(a)arm.com>
> Subject: Re: [TF-M] [RFC] Code restructure of core/spm
>
> Hi,
> The first patch for moving header files is ready at:
> https://review.trustedfirmware.org/c/trusted-firmware-m/+/1561
> Comments are welcome. I had thought to push patches together but looks
> like it would block other patches for a while to show a neat merged
> list, so I would push them one by one.
>
> Will keep you update when incoming patches are ready.
>
> BR
>
> /Ken
>
> > -----Original Message-----
> > From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken
> > Liu (Arm Technology China) via TF-M
> > Sent: Thursday, August 1, 2019 11:12 AM
> > To: tf-m(a)lists.trustedfirmware.org
> > Cc: nd <nd(a)arm.com>
> > Subject: [TF-M] [RFC] Code restructure of core/spm
> >
> > Hi,
> >
> > Several patches for code restructure is coming. Before I post the
> > gerrit items, I want to collect your feedback on this. These changes contain:
> >
> > - Move header files into dedicated directory for easy include, and
> > clean the included headers in sources;
> > - Change some files' name to let them make more sense.
> > - Move SPM related files into 'spm' folder instead of putting them in 'core'.
> > - Move some interface files into 'ns_callable' since they are interfaces.
> > - Remove 'ipc' folder after all files in it are well arranged.
> >
> > I will try to do these patches together so they can be merged together.
> > But before that I want to request for comments about this, feel free
> > to reply in this thread or comment on the task (add yourself if you
> > are missing as
> > subscribers):
> > https://developer.trustedfirmware.org/T426
> >
> > BR
> >
> > /Ken
> >
> >
> > --
> > TF-M mailing list
> > TF-M(a)lists.trustedfirmware.org
> > https://lists.trustedfirmware.org/mailman/listinfo/tf-m
> --
> TF-M mailing list
> TF-M(a)lists.trustedfirmware.org
> https://lists.trustedfirmware.org/mailman/listinfo/tf-m
--
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Hi Reinhard & Ken,
There are definitely some challenging trade-offs, and the right approach can depend on the system and use case.
PSA Firmware Framework is a architectural interface design for deployment on different CPU/SoC designs, and defines an interrupt framework that:
1. can be implemented on these different architectures
2. is aligned with the security & isolation principles of the Framework
PSA-FF does not stop an implementation (such as TF-M) from providing additional interrupt frameworks that provide lower-latency for some components. These will obviously be non-portable (to other PSA-FF implementations) and may have security trade-offs if the ISR runs in a privileged secure state to achieve performance requirements.
As you suggest, although it is possible to discuss the options in general - it is only possible to make good design decisions with real use cases for integrating hardware devices into the secure side of the system, and the required behaviour of the interrupt handlers.
There is a substantial evidence that weakening the isolation requirements is not typically balanced by keeping the critical code simple, reviewed and secure - based on the experience of TrustZone and other TEE software implementations. I agree that such careful code development is possible, but it is not normal (at the moment).
Regards,
Andrew
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: 18 December 2019 13:49
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] irq handling in library mode
Ken, thanks for the reply.
My take on that is that instead of adding overhead to ISR, ISR should be executed fast.
For ISRs we should publish clear guidelines that explain potential side effects of ISR execution.
These guidelines should advocate that ISR is kept short, and workload is off-loaded to thread execution.
How this is exactly done in secure side needs to be defined, as the RTOS (on non-secure side) might inconsistent and not be available.
What would be really good is to have typical ISR routines that execute in secure side. This would better allow us to judge what is really needed. I believe most of them are small anyway.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi Matt,
Sorry not to review your patch as soon as possible because you forget adding me to the reviewer list😊
I had reviewed it now.
By the way, there is a contributing process in TF-M which require to create a related ‘task’ for task management. I had helped to create one for this issue. Please help to create it the next time. I can help you if you have any problems with it. For more detail, you can refer to this:https://git.trustedfirmware.org/trusted-firmware-m.git/tree/docs/proce…,
Hi All,
Here is the patch link: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2923. Please help to review it
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Matt via TF-M
Sent: Friday, December 20, 2019 12:49 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] irq handling in library mode
Hi Edison,
If it is a bug, I will upsteam a patch to fix it later.
Thanks,
Matt
Hi Edison,
If it is a bug, I will upsteam a patch to fix it later.
Thanks,
Matt
At 2019-12-19 16:43:18, "Edison Ai via TF-M" <tf-m(a)lists.trustedfirmware.org> wrote:
Hi Matt,
Sorry not got your point in the first time.
Yes, you are right. It is indeed a bug here. And thanks for your detail explaining and good example.
Can you upstream a patch to fix it?
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Wednesday, December 18, 2019 9:54 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] irq handling in library mode
Hi Edison,
Thanks for your reply.
In file tfm_secure_irq_handling.rst, we can know every SP have a continuous irq related stack as follows,
|
interrupted_ctx_stack_frame_t
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
|
...
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
And this stack pointer is saved in the field ctx_stack_ptr of structure spm_partition_runtime_data_t for each partition.
If partition A is interrupted for the first time by a lower priority interrupt, as current code shown bellow, the interrupted_ctx_stack_frame_t will be pushed at the beginning of the irq stack.
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
Now the stack is show as below,
|
interrupted_ctx_stack_frame_t (used)
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
|
...
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
But the stack pointer is not moved upper after pushing interrupted_ctx_stack_frame_t, so the ctx_stack_ptr is still point to the beginning of the stack.
At this time,if a higher priority interrupt of partition A is coming, partition A becomes handler partition, so the structure handler_ctx_stack_frame_t should be pushed in
the stack of partition A, as current code shown below,
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
As it shown above, the content of handler_ctx_stack_frame_t will be overlapped with already pushed content of interrupted_ctx_stack_frame_t.
My question is exactly about the above scenario.
If the stack pointer is also moved upper after pushing the interrupted_ctx_stack_frame_t, handler_ctx_stack_frame_t will be pushed at different location in the stack as follows,
|
interrupted_ctx_stack_frame_t (used)
|
|
handler_ctx_stack_frame_t (used)
|
|
interrupted_ctx_stack_frame_t
|
|
...
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
Please read the file tfm_secure_irq_handling.rst again , and help to check about this question.
Thanks,
Matt
At 2019-12-17 14:22:13, "Edison Ai \\(Arm Technology China\\) via TF-M" <tf-m(a)lists.trustedfirmware.org> wrote:
Hi Matt,
Thanks for your email.
Let me try to answer your question because of the designer of the TF-M interrupt handling is on leave now.
First, you are right about this: “If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.”
Let’s start from an example, there are 3 SPs with different interrupt priority, SP1 < SP2 < SP3. And there is one scenario like this:
SP1 is running, SP2 interrupt SP1. Current, the interrupted partition is SP1, and the handler partition is SP2.
As the below code show in tfm_spm_partition_push_handler_ctx(), the stack pointer will be moved upper as below:
|
SP2 stack pointer -à
|
|
|
|
Caller_partition_indx(handler)
|
|
|
Partition_sate(handler)
|
SP2 starts to run, and it is interrupted by SP3. Current, the interrupted partition is SP2, and the handler partition is SP3.
As the code shown in tfm_spm_partition_push_interrupted_ctx(), it uses the current stack member directly without moving its pointer.
|
SP2 stack pointer -à
|
Partition_state(interrupted)
|
|
|
Caller_partition_indx(handler)
|
|
|
Partition_sate(handler)
|
And after SP2 is interrupted by SP3, its partition status will be changed to “SPM_PARTITION_STATE_SUSPENDED”. So that this partition will not be interrupted by others anymore unless it comes back to running state. Which means it does not need more stack anymore.
We can consider that after one SP is interrupted by others, there is no more stack is needed for it before it comes back to running status.
So I think it should be ok in the current design for the interrupt in the library model.
I am not sure if this can solve your confuse. Please feel free to give feedback. We can discuss more about it.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Monday, December 16, 2019 1:08 PM
To:tf-m@lists.trustedfirmware.org
Subject: [TF-M] irq handling in library mode
Hi TFM experts,
I have a question about the code logic of irq handling in library mode, code blocks in spm_api_func.c are as follows:
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
My question is why there is not the following such code logic at the end of function tfm_spm_partition_push_interrupted_ctx.
runtime_data->ctx_stack_ptr +=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.
And when pop the stack frame after handling irq, there is the following code logic in tfm_spm_partition_pop_handler_ctx
runtime_data->ctx_stack_ptr -=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
I think the same logic of changing ctx_stack_ptr should be added the begining of the function tfm_spm_partition_pop_interrupted_ctx like the above code logic in tfm_spm_partition_pop_handler_ctx.
runtime_data->ctx_stack_ptr -=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
Please help to check.
Thanks,
Matt
Hello,
We have a new blog post detailing TF-M in Lyon here: https://www.trustedfirmware.org/blog/trusted_firmware_at_lyon/
Thank you,
Augustina Adjei
[cid:image001.jpg@01D5B688.34C152B0]
Mawuelome - Seyram Augustina Adjei
Central Engineering - Open Source Software Group
augustina.adjei(a)arm.com
110 Fulbourn Road, Cambridge, CB1 9NJ
www.arm.com<http://www.arm.com/>
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi all,
The triggering behavior of the Trusted Firmware-M CI has been adjusted. Tests jobs will no longer trigger automatically. Instead when the patch submitter would like their code to be tested, they will need to assert the newly introduced `Allow-CI` Gerrit voting flag.
Regards
Minos
Because of New Year holidays, the next forum is planned on Jan 9, 2020.
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Wang via TF-M
Sent: 19 December 2019 02:37
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] TF-M Technical Forum call - 19th December
Update the Agenda: (added TF-M profile session)
- The interrupts' topic was followed by email and looks like closed. Are there remaining points for discussion?
- TF-M and Amazon FreeRTOS integration update
- [RFC] TF-M Profile
- Cryptocell integration
Regards,
David Wang
Arm Electronic Technology (Shanghai) Co., Ltd
Phone: +86-21-6154 9142 (ext. 59142)
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Anton Komlev via TF-M
Sent: Friday, December 13, 2019 2:14 AM
To: TF-M(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] TF-M Technical Forum call - 19th December
Hello,
To continuing our open discussion, started a week ago let me propose the 2nd session and create this mail thread to discuss related topics.
1. The time slot.
Looking on participants' distribution [Asia:6, Europe:20, US East:1, US Cent:1, US West:4, Total:32] I see the majority is in Europe. The Asian region could be more presented giving a more comfortable time. Having this in mind, I would propose to have the 2nd session on Dec 19 at 7:00 UTC time. This compromise gives US West coast a chance to join at 23:00 (Dec 18!). Here is the summary:
https://www.timeanddate.com/worldclock/meetingdetails.html?year=2019&month=…
Please share your thoughts and alternatives. The related question: shall we fix the time or rotating?
You can play with the time slot here:
https://www.timeanddate.com/worldclock/meetingtime.html?day=19&month=12&yea…
2. Agenda as a proposal
- The interrupts' topic was followed by email and looks like closed. Are there remaining points for discussion?
- TF-M and Amazon FreeRTOS integration update
- Cryptocell integration
- ?
Best regards,
Anton Komlev
--
TF-M mailing list
TF-M(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/tf-m
--
TF-M mailing list
TF-M(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/tf-m
Hi Matt,
Sorry not got your point in the first time.
Yes, you are right. It is indeed a bug here. And thanks for your detail explaining and good example.
Can you upstream a patch to fix it?
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Wednesday, December 18, 2019 9:54 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] irq handling in library mode
Hi Edison,
Thanks for your reply.
In file tfm_secure_irq_handling.rst, we can know every SP have a continuous irq related stack as follows,
interrupted_ctx_stack_frame_t
handler_ctx_stack_frame_t
interrupted_ctx_stack_frame_t
...
handler_ctx_stack_frame_t
interrupted_ctx_stack_frame_t
And this stack pointer is saved in the field ctx_stack_ptr of structure spm_partition_runtime_data_t for each partition.
If partition A is interrupted for the first time by a lower priority interrupt, as current code shown bellow, the interrupted_ctx_stack_frame_t will be pushed at the beginning of the irq stack.
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
Now the stack is show as below,
interrupted_ctx_stack_frame_t (used)
handler_ctx_stack_frame_t
interrupted_ctx_stack_frame_t
...
handler_ctx_stack_frame_t
interrupted_ctx_stack_frame_t
But the stack pointer is not moved upper after pushing interrupted_ctx_stack_frame_t, so the ctx_stack_ptr is still point to the beginning of the stack.
At this time,if a higher priority interrupt of partition A is coming, partition A becomes handler partition, so the structure handler_ctx_stack_frame_t should be pushed in
the stack of partition A, as current code shown below,
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
As it shown above, the content of handler_ctx_stack_frame_t will be overlapped with already pushed content of interrupted_ctx_stack_frame_t.
My question is exactly about the above scenario.
If the stack pointer is also moved upper after pushing the interrupted_ctx_stack_frame_t, handler_ctx_stack_frame_t will be pushed at different location in the stack as follows,
interrupted_ctx_stack_frame_t (used)
handler_ctx_stack_frame_t (used)
interrupted_ctx_stack_frame_t
...
handler_ctx_stack_frame_t
interrupted_ctx_stack_frame_t
Please read the file tfm_secure_irq_handling.rst again , and help to check about this question.
Thanks,
Matt
At 2019-12-17 14:22:13, "Edison Ai \\(Arm<file://(Arm> Technology China\\) via TF-M" <tf-m(a)lists.trustedfirmware.org<mailto:tf-m@lists.trustedfirmware.org>> wrote:
Hi Matt,
Thanks for your email.
Let me try to answer your question because of the designer of the TF-M interrupt handling is on leave now.
First, you are right about this: "If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location."
Let's start from an example, there are 3 SPs with different interrupt priority, SP1 < SP2 < SP3. And there is one scenario like this:
* SP1 is running, SP2 interrupt SP1. Current, the interrupted partition is SP1, and the handler partition is SP2.
As the below code show in tfm_spm_partition_push_handler_ctx(), the stack pointer will be moved upper as below:
SP2 stack pointer --->
Caller_partition_indx(handler)
Partition_sate(handler)
*
SP2 starts to run, and it is interrupted by SP3. Current, the interrupted partition is SP2, and the handler partition is SP3.
As the code shown in tfm_spm_partition_push_interrupted_ctx(), it uses the current stack member directly without moving its pointer.
SP2 stack pointer --->
Partition_state(interrupted)
Caller_partition_indx(handler)
Partition_sate(handler)
And after SP2 is interrupted by SP3, its partition status will be changed to "SPM_PARTITION_STATE_SUSPENDED". So that this partition will not be interrupted by others anymore unless it comes back to running state. Which means it does not need more stack anymore.
We can consider that after one SP is interrupted by others, there is no more stack is needed for it before it comes back to running status.
So I think it should be ok in the current design for the interrupt in the library model.
I am not sure if this can solve your confuse. Please feel free to give feedback. We can discuss more about it.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org<mailto:tf-m-bounces@lists.trustedfirmware.org>> On Behalf Of lg via TF-M
Sent: Monday, December 16, 2019 1:08 PM
To: tf-m(a)lists.trustedfirmware.org<mailto:tf-m@lists.trustedfirmware.org>
Subject: [TF-M] irq handling in library mode
Hi TFM experts,
I have a question about the code logic of irq handling in library mode, code blocks in spm_api_func.c are as follows:
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
My question is why there is not the following such code logic at the end of function tfm_spm_partition_push_interrupted_ctx.
runtime_data->ctx_stack_ptr +=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.
And when pop the stack frame after handling irq, there is the following code logic in tfm_spm_partition_pop_handler_ctx
runtime_data->ctx_stack_ptr -=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
I think the same logic of changing ctx_stack_ptr should be added the begining of the function tfm_spm_partition_pop_interrupted_ctx like the above code logic in tfm_spm_partition_pop_handler_ctx.
runtime_data->ctx_stack_ptr -=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
Please help to check.
Thanks,
Matt
Update the Agenda: (added TF-M profile session)
- The interrupts' topic was followed by email and looks like closed. Are there remaining points for discussion?
- TF-M and Amazon FreeRTOS integration update
- [RFC] TF-M Profile
- Cryptocell integration
Regards,
David Wang
Arm Electronic Technology (Shanghai) Co., Ltd
Phone: +86-21-6154 9142 (ext. 59142)
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Anton Komlev via TF-M
Sent: Friday, December 13, 2019 2:14 AM
To: TF-M(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] TF-M Technical Forum call - 19th December
Hello,
To continuing our open discussion, started a week ago let me propose the 2nd session and create this mail thread to discuss related topics.
1. The time slot.
Looking on participants' distribution [Asia:6, Europe:20, US East:1, US Cent:1, US West:4, Total:32] I see the majority is in Europe. The Asian region could be more presented giving a more comfortable time. Having this in mind, I would propose to have the 2nd session on Dec 19 at 7:00 UTC time. This compromise gives US West coast a chance to join at 23:00 (Dec 18!). Here is the summary:
https://www.timeanddate.com/worldclock/meetingdetails.html?year=2019&month=…
Please share your thoughts and alternatives. The related question: shall we fix the time or rotating?
You can play with the time slot here:
https://www.timeanddate.com/worldclock/meetingtime.html?day=19&month=12&yea…
2. Agenda as a proposal
- The interrupts' topic was followed by email and looks like closed. Are there remaining points for discussion?
- TF-M and Amazon FreeRTOS integration update
- Cryptocell integration
- ?
Best regards,
Anton Komlev
--
TF-M mailing list
TF-M(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/tf-m
Hi Edison,
Thanks for your reply.
In file tfm_secure_irq_handling.rst, we can know every SP have a continuous irq related stack as follows,
|
interrupted_ctx_stack_frame_t
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
|
...
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
And this stack pointer is saved in the field ctx_stack_ptr of structure spm_partition_runtime_data_t for each partition.
If partition A is interrupted for the first time by a lower priority interrupt, as current code shown bellow, the interrupted_ctx_stack_frame_t will be pushed at the beginning of the irq stack.
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
Now the stack is show as below,
|
interrupted_ctx_stack_frame_t (used)
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
|
...
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
But the stack pointer is not moved upper after pushing interrupted_ctx_stack_frame_t, so the ctx_stack_ptr is still point to the beginning of the stack.
At this time,if a higher priority interrupt of partition A is coming, partition A becomes handler partition, so the structure handler_ctx_stack_frame_t should be pushed in
the stack of partition A, as current code shown below,
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
As it shown above, the content of handler_ctx_stack_frame_t will be overlapped with already pushed content of interrupted_ctx_stack_frame_t.
My question is exactly about the above scenario.
If the stack pointer is also moved upper after pushing the interrupted_ctx_stack_frame_t, handler_ctx_stack_frame_t will be pushed at different location in the stack as follows,
|
interrupted_ctx_stack_frame_t (used)
|
|
handler_ctx_stack_frame_t (used)
|
|
interrupted_ctx_stack_frame_t
|
|
...
|
|
handler_ctx_stack_frame_t
|
|
interrupted_ctx_stack_frame_t
|
Please read the file tfm_secure_irq_handling.rst again , and help to check about this question.
Thanks,
Matt
At 2019-12-17 14:22:13, "Edison Ai \\(Arm Technology China\\) via TF-M" <tf-m(a)lists.trustedfirmware.org> wrote:
Hi Matt,
Thanks for your email.
Let me try to answer your question because of the designer of the TF-M interrupt handling is on leave now.
First, you are right about this: “If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.”
Let’s start from an example, there are 3 SPs with different interrupt priority, SP1 < SP2 < SP3. And there is one scenario like this:
SP1 is running, SP2 interrupt SP1. Current, the interrupted partition is SP1, and the handler partition is SP2.
As the below code show in tfm_spm_partition_push_handler_ctx(), the stack pointer will be moved upper as below:
|
SP2 stack pointer -à
|
|
|
|
Caller_partition_indx(handler)
|
|
|
Partition_sate(handler)
|
SP2 starts to run, and it is interrupted by SP3. Current, the interrupted partition is SP2, and the handler partition is SP3.
As the code shown in tfm_spm_partition_push_interrupted_ctx(), it uses the current stack member directly without moving its pointer.
|
SP2 stack pointer -à
|
Partition_state(interrupted)
|
|
|
Caller_partition_indx(handler)
|
|
|
Partition_sate(handler)
|
And after SP2 is interrupted by SP3, its partition status will be changed to “SPM_PARTITION_STATE_SUSPENDED”. So that this partition will not be interrupted by others anymore unless it comes back to running state. Which means it does not need more stack anymore.
We can consider that after one SP is interrupted by others, there is no more stack is needed for it before it comes back to running status.
So I think it should be ok in the current design for the interrupt in the library model.
I am not sure if this can solve your confuse. Please feel free to give feedback. We can discuss more about it.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Monday, December 16, 2019 1:08 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] irq handling in library mode
Hi TFM experts,
I have a question about the code logic of irq handling in library mode, code blocks in spm_api_func.c are as follows:
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
My question is why there is not the following such code logic at the end of function tfm_spm_partition_push_interrupted_ctx.
runtime_data->ctx_stack_ptr +=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.
And when pop the stack frame after handling irq, there is the following code logic in tfm_spm_partition_pop_handler_ctx
runtime_data->ctx_stack_ptr -=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
I think the same logic of changing ctx_stack_ptr should be added the begining of the function tfm_spm_partition_pop_interrupted_ctx like the above code logic in tfm_spm_partition_pop_handler_ctx.
runtime_data->ctx_stack_ptr -=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
Please help to check.
Thanks,
Matt
Ken, thanks for the reply.
My take on that is that instead of adding overhead to ISR, ISR should be executed fast.
For ISRs we should publish clear guidelines that explain potential side effects of ISR execution.
These guidelines should advocate that ISR is kept short, and workload is off-loaded to thread execution.
How this is exactly done in secure side needs to be defined, as the RTOS (on non-secure side) might inconsistent and not be available.
What would be really good is to have typical ISR routines that execute in secure side. This would better allow us to judge what is really needed. I believe most of them are small anyway.
Reinhard
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Ken thanks for your answer.
So it is up to the PSA Framework team to define the right framework?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
ARM Germany GmbH | Bretonischer Ring 16 | D-85630 Grasbrunn,Germany
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We already have about 7 test services/partitions. It's growing.
To save resources. Is it possible to combine the test partitions to one or just few?
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Jamie Fox via TF-M
Sent: Wednesday, December 18, 2019 12:34 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Adding a new test partition to test multi-partition scenarios
Hi all,
There's a need to test service features in TF-M involving more than one partition taking certain actions. For example, the ITS service implements access control for assets in storage based on the partition ID of the client, so we want to test the case where one partition attempts to access an asset belonging to another. There is a similar scenario for Crypto involving access control for keys.
Previously we have tested the same feature in SST with multiple NS RTOS threads, relying on the NS RTOS to provide distinct client IDs for each, but as NS client identification may not always be available this is not the ideal solution.
I am proposing we add a 'Secure Client 2' test partition to act as slave for the Secure Client (1) test partition that executes the secure test suites. The new partition provides a service to call test functions by ID within its execution context and return the resulting status to the caller. The initial implementation is here: https://review.trustedfirmware.org/c/trusted-firmware-m/+/2838<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Freview.tr…> . For now it is as simple as possible, just provides one API to call functions by ID, no support for passing other arguments, but we can extend when there is a need for more features.
Here I have implemented a basic test for ITS access control using the new partition: https://review.trustedfirmware.org/c/trusted-firmware-m/+/2790<https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Freview.tr…>
Kind regards,
Jamie
Hi all,
There's a need to test service features in TF-M involving more than one partition taking certain actions. For example, the ITS service implements access control for assets in storage based on the partition ID of the client, so we want to test the case where one partition attempts to access an asset belonging to another. There is a similar scenario for Crypto involving access control for keys.
Previously we have tested the same feature in SST with multiple NS RTOS threads, relying on the NS RTOS to provide distinct client IDs for each, but as NS client identification may not always be available this is not the ideal solution.
I am proposing we add a 'Secure Client 2' test partition to act as slave for the Secure Client (1) test partition that executes the secure test suites. The new partition provides a service to call test functions by ID within its execution context and return the resulting status to the caller. The initial implementation is here: https://review.trustedfirmware.org/c/trusted-firmware-m/+/2838 . For now it is as simple as possible, just provides one API to call functions by ID, no support for passing other arguments, but we can extend when there is a need for more features.
Here I have implemented a basic test for ITS access control using the new partition: https://review.trustedfirmware.org/c/trusted-firmware-m/+/2790
Kind regards,
Jamie
Hi,
"... with 80 column while reviewing (not put this into document) ... "
FIY our coding standard explicitly requires 80 chars limit for C code. (See: https://ci.trustedfirmware.org/job/tf-m-build-test-nightly/lastSuccessfulBu… )
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Ken Liu via TF-M
Sent: 18 December 2019 02:04
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Coding guideline
Hi,
For me both 100 or 80 are acceptable for c sources, and no limit for scripts/makefiles.
But at current I am trying to limit the core/spm source with 80 column while reviewing (not put this into document) because it works well under default gerrit setting and easies the review.
For services, I won't propose specified limits because some of them may be external projects which is hard to be limited.
/Ken
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Gyorgy Szing via TF-M
Sent: Wednesday, December 18, 2019 12:40 AM
To: David Brown <david.brown(a)linaro.org>; Reinhard Keil <Reinhard.Keil(a)arm.com>; tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Coding guideline
Hi,
One limit we have to regularly face is imposed by the gerrit diff view (i.e: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2560/6/bl2/ext/… ). It might be worth to check how many characters do fit the half of the view on a full-hd monitor with default font size settings in modern browsers (chrome, firefox, etc..). (In my environment the limit seems to be around 100.) Of course unified view may help (i.e. https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2560/6/bl2/ext/…), but we should try to avoid limiting UI usage as much as possible.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Brown via TF-M
Sent: 17 December 2019 17:17
To: Reinhard Keil <Reinhard.Keil(a)arm.com>
Cc: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] Coding guideline
On Tue, Dec 17, 2019 at 08:58:13AM +0000, Reinhard Keil via TF-M wrote:
> IMHO a 80-char restriction is irrelevant with today’s screens/editors
> – it comes from the teletype time where 80 characters was the natural
> limit on CRT or punch card.
I do tend to agree to this. I still think it is useful to have a limit, but something like 100 or even 120 makes a lot more sense.
However, even though we have bigger screens, it is still useful to have multiple smaller terminal windows rather than just one big one.
But, for myself, I tend to always have them at least be 100 characters.
David
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Hi Reinhard,
This is correct at current and needs SFC specification to clarification in future.
The existing PSA Firmware Framework proposes a thread based Secure Partition and the IPC manner about how the information is shared between these process.
The SFC model (which is a well know model but do not have a specification yet) combines secure services as a library and makes the information-sharing mechanism complicate under isolation level 2/3, which lost the advantage of 'library' model.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: Tuesday, December 17, 2019 4:10 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] Level 2/Level 3 Isolation requires IPC?
I have heard that Level 2/Level 3 isolation with TF-M requires Inter-Process Communication (IPC) mode.
It does not work with Secure Function Call (SFC) mode (aka Library mode).
Is it correct, and why does Level2/Level 3 isolation require IPC?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
ARM Germany GmbH | Bretonischer Ring 16 | D-85630 Grasbrunn,Germany
Sitz der Gesellschaft: Grasbrunn | Handelsregister: München (HRB 175362)
Geschäftsführer: Andrew Smith, Joachim Krech, Reinhard Keil
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi Reinhard,
Your approach is good for a RTOS.
For secure firmware, we need to:
* A secure partition may bind an interrupt in its manifest, which means the interrupt related logic of a secure partition should be inside secure partition's scope. (This is what the library model is doing.)
* To avoid affect non-secure RTOS execution, IRQ should be quick and heavy execution can be delay into secure partition thread. (This is what IPC model is doing).
This interrupt handling is keeping evolution, we are trying to create a proposal to provide:
* Fast ISR execution.
* Put non-urgent interrupt related logic into thread.
Now we are collecting proposals and your comment is an important input. And I think the DMA part needs to be considerate much as you have mentioned, it may bypass MPU.
If anyone is also working on this topic, please send mail in this mailing list or create an issue (developer.trustedfirmware.org).
Thanks.
/Ken
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: Tuesday, December 17, 2019 4:04 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] irq handling in library mode
I would argue that "IRQ handling" should just be standard v8M hardware behaviour for the following rational:
* IRQ routines should be short and simple by nature - it is therefore relative easy to fully verify it and ensure that there are no side effects.
* IRQ should be therefore executed in handler mode using MSP, no MPU protection, only protection via SAU, PPC, MPC.
Another reason of this relaxed approach is the usage of DMA.
* DMA is frequently controlled by IRQ
* DMA also bypasses MPU, therefore same behaviour as IRQ.
Overall this approach ensures simple, fast IRQ execution (sales argument of v8M) and reduces risk software glitches in TF-M Core.
What is wrong with that approach?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
ARM Germany GmbH | Bretonischer Ring 16 | D-85630 Grasbrunn,Germany
Sitz der Gesellschaft: Grasbrunn | Handelsregister: München (HRB 175362)
Geschäftsführer: Andrew Smith, Joachim Krech, Reinhard Keil
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi,
For me both 100 or 80 are acceptable for c sources, and no limit for scripts/makefiles.
But at current I am trying to limit the core/spm source with 80 column while reviewing (not put this into document) because it works well under default gerrit setting and easies the review.
For services, I won't propose specified limits because some of them may be external projects which is hard to be limited.
/Ken
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Gyorgy Szing via TF-M
Sent: Wednesday, December 18, 2019 12:40 AM
To: David Brown <david.brown(a)linaro.org>; Reinhard Keil <Reinhard.Keil(a)arm.com>; tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Coding guideline
Hi,
One limit we have to regularly face is imposed by the gerrit diff view (i.e: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2560/6/bl2/ext/… ). It might be worth to check how many characters do fit the half of the view on a full-hd monitor with default font size settings in modern browsers (chrome, firefox, etc..). (In my environment the limit seems to be around 100.) Of course unified view may help (i.e. https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2560/6/bl2/ext/…), but we should try to avoid limiting UI usage as much as possible.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Brown via TF-M
Sent: 17 December 2019 17:17
To: Reinhard Keil <Reinhard.Keil(a)arm.com>
Cc: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] Coding guideline
On Tue, Dec 17, 2019 at 08:58:13AM +0000, Reinhard Keil via TF-M wrote:
> IMHO a 80-char restriction is irrelevant with today’s screens/editors
> – it comes from the teletype time where 80 characters was the natural
> limit on CRT or punch card.
I do tend to agree to this. I still think it is useful to have a limit, but something like 100 or even 120 makes a lot more sense.
However, even though we have bigger screens, it is still useful to have multiple smaller terminal windows rather than just one big one.
But, for myself, I tend to always have them at least be 100 characters.
David
--
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TF-M(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/tf-m
--
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Hi,
One limit we have to regularly face is imposed by the gerrit diff view (i.e: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2560/6/bl2/ext/… ). It might be worth to check how many characters do fit the half of the view on a full-hd monitor with default font size settings in modern browsers (chrome, firefox, etc..). (In my environment the limit seems to be around 100.)
Of course unified view may help (i.e. https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2560/6/bl2/ext/…), but we should try to avoid limiting UI usage as much as possible.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Brown via TF-M
Sent: 17 December 2019 17:17
To: Reinhard Keil <Reinhard.Keil(a)arm.com>
Cc: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] Coding guideline
On Tue, Dec 17, 2019 at 08:58:13AM +0000, Reinhard Keil via TF-M wrote:
> IMHO a 80-char restriction is irrelevant with today’s screens/editors
> – it comes from the teletype time where 80 characters was the natural
> limit on CRT or punch card.
I do tend to agree to this. I still think it is useful to have a limit, but something like 100 or even 120 makes a lot more sense.
However, even though we have bigger screens, it is still useful to have multiple smaller terminal windows rather than just one big one.
But, for myself, I tend to always have them at least be 100 characters.
David
--
TF-M mailing list
TF-M(a)lists.trustedfirmware.org
https://lists.trustedfirmware.org/mailman/listinfo/tf-m
On Tue, Dec 17, 2019 at 08:58:13AM +0000, Reinhard Keil via TF-M wrote:
> IMHO a 80-char restriction is irrelevant with today’s screens/editors – it
> comes from the teletype time where 80 characters was the natural limit on CRT
> or punch card.
I do tend to agree to this. I still think it is useful to have a
limit, but something like 100 or even 120 makes a lot more sense.
However, even though we have bigger screens, it is still useful to
have multiple smaller terminal windows rather than just one big one.
But, for myself, I tend to always have them at least be 100
characters.
David
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Has there been any conclusion on coding guidelines.
IMHO a 80-char restriction is irrelevant with today's screens/editors - it comes from the teletype time where 80 characters was the natural limit on CRT or punch card.
MISRA in contrast is industry standard and a fundamental requirement in many projects. What is the progress here?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
ARM Germany GmbH | Bretonischer Ring 16 | D-85630 Grasbrunn,Germany
Sitz der Gesellschaft: Grasbrunn | Handelsregister: München (HRB 175362)
Geschäftsführer: Andrew Smith, Joachim Krech, Reinhard Keil
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
I have heard that Level 2/Level 3 isolation with TF-M requires Inter-Process Communication (IPC) mode.
It does not work with Secure Function Call (SFC) mode (aka Library mode).
Is it correct, and why does Level2/Level 3 isolation require IPC?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
ARM Germany GmbH | Bretonischer Ring 16 | D-85630 Grasbrunn,Germany
Sitz der Gesellschaft: Grasbrunn | Handelsregister: München (HRB 175362)
Geschäftsführer: Andrew Smith, Joachim Krech, Reinhard Keil
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
I would argue that "IRQ handling" should just be standard v8M hardware behaviour for the following rational:
* IRQ routines should be short and simple by nature - it is therefore relative easy to fully verify it and ensure that there are no side effects.
* IRQ should be therefore executed in handler mode using MSP, no MPU protection, only protection via SAU, PPC, MPC.
Another reason of this relaxed approach is the usage of DMA.
* DMA is frequently controlled by IRQ
* DMA also bypasses MPU, therefore same behaviour as IRQ.
Overall this approach ensures simple, fast IRQ execution (sales argument of v8M) and reduces risk software glitches in TF-M Core.
What is wrong with that approach?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
ARM Germany GmbH | Bretonischer Ring 16 | D-85630 Grasbrunn,Germany
Sitz der Gesellschaft: Grasbrunn | Handelsregister: München (HRB 175362)
Geschäftsführer: Andrew Smith, Joachim Krech, Reinhard Keil
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Hi,
I will be collecting for new review comments till this Friday.
If there were no new comments, I will get the patches merged after addressing the existing comments.
Best Regards,
Kevin
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Kevin Peng (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 11:02 AM
To: 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Support for optional build for secure partitions and test suites
Hi,
I've made some patches to support optional build for secure partitions and test suites:
https://review.trustedfirmware.org/q/topic:%22optional_build_sp_and_tests%2…
With this patch set, you can optionally build secure partitions by setting the TFM_PARTITION_XXX in CommonConfig.cmake around line 152 - 162.
And for test suites, by setting ENABLE_XXX_TESTS in test/TestConfig.cmake.
I'm collecting for review comments. Thanks.
Best Regards,
Kevin
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Hi Matt,
Thanks for your email.
Let me try to answer your question because of the designer of the TF-M interrupt handling is on leave now.
First, you are right about this: "If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location."
Let's start from an example, there are 3 SPs with different interrupt priority, SP1 < SP2 < SP3. And there is one scenario like this:
* SP1 is running, SP2 interrupt SP1. Current, the interrupted partition is SP1, and the handler partition is SP2.
As the below code show in tfm_spm_partition_push_handler_ctx(), the stack pointer will be moved upper as below:
SP2 stack pointer --->
Caller_partition_indx(handler)
Partition_sate(handler)
* SP2 starts to run, and it is interrupted by SP3. Current, the interrupted partition is SP2, and the handler partition is SP3.
As the code shown in tfm_spm_partition_push_interrupted_ctx(), it uses the current stack member directly without moving its pointer.
SP2 stack pointer --->
Partition_state(interrupted)
Caller_partition_indx(handler)
Partition_sate(handler)
And after SP2 is interrupted by SP3, its partition status will be changed to "SPM_PARTITION_STATE_SUSPENDED". So that this partition will not be interrupted by others anymore unless it comes back to running state. Which means it does not need more stack anymore.
We can consider that after one SP is interrupted by others, there is no more stack is needed for it before it comes back to running status.
So I think it should be ok in the current design for the interrupt in the library model.
I am not sure if this can solve your confuse. Please feel free to give feedback. We can discuss more about it.
Thanks,
Edison
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Monday, December 16, 2019 1:08 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] irq handling in library mode
Hi TFM experts,
I have a question about the code logic of irq handling in library mode, code blocks in spm_api_func.c are as follows:
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
My question is why there is not the following such code logic at the end of function tfm_spm_partition_push_interrupted_ctx.
runtime_data->ctx_stack_ptr +=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.
And when pop the stack frame after handling irq, there is the following code logic in tfm_spm_partition_pop_handler_ctx
runtime_data->ctx_stack_ptr -=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
I think the same logic of changing ctx_stack_ptr should be added the begining of the function tfm_spm_partition_pop_interrupted_ctx like the above code logic in tfm_spm_partition_pop_handler_ctx.
runtime_data->ctx_stack_ptr -=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
Please help to check.
Thanks,
Matt
Hi Thomas,
What I can see from your description is that the problem should is caused the MPU configure.
You are working on the isolation level 2 model by using ConfigRegressionIPCTfmLevel2 configure file.
In isolation level 2, PSA FF says this: "the PSA Root of Trust is also protected from access by the Application Root of Trust". You can see more detail about the isolation information from PSA FF with this link: https://pages.arm.com/psa-resources-ff.html?_ga=2.156169596.61580709.154261….
So, we need to configure MPU(MSUCA_A board which you are using) for APP RoT to limit the source the APP RoT can access in isolation level 2.
You can see from code:
__attribute__((naked, section("SFN")))
psa_signal_t psa_wait(psa_signal_t signal_mask, uint32_t timeout)
{
__ASM volatile("SVC %0 \n"
"BX LR \n"
: : "I" (TFM_SVC_PSA_WAIT)); }
The psa_wait() is put in the "SFN" region, and the "SFN" region in put in the "TFM_UNPRIV_CODE" section. You can see the information about the "TFM_UNPRIV_CODE" in platform/ext/common/armclang/tfm_common_s.sct.
You can refer tfm_spm_mpu_init() in platfrom/ext/target/musca_a/spm_hal.c. There are some MPU region we need to configure for APP RoT in isolation level 2, include the "TFM_UNPRIV_CODE".
If you are interested, you can see some detail about the design of isolation level 2 from here: https://developer.trustedfirmware.org/w/tf_m/design/trusted_firmware-m_isol…
Please check this first. If cannot work, please feel free to tell us.
Thanks,
Edison
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Thomas Törnblom via TF-M
Sent: Friday, December 13, 2019 4:25 AM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] MPU issues, was Re: Regression test issues with IAR port
Next issue.
For some reason the secure image runs into a MemManage exception fairly early in the irq test of the ConfigRegressionIPCTfmLevel2 config and I have not yet been able to figure out why.
It happens in the psa_wait() call in:
---
int32_t tfm_irq_test_1_init(void)
{
tfm_enable_irq(SPM_CORE_IRQ_TEST_1_SIGNAL_TIMER_0_IRQ);
#ifdef TFM_PSA_API
psa_signal_t signals = 0;
while (1) {
signals = psa_wait(PSA_WAIT_ANY, PSA_BLOCK);
---
The exact point of the exception is the SVC call in:
---
__attribute__((naked, section("SFN")))
psa_signal_t psa_wait(psa_signal_t signal_mask, uint32_t timeout)
{
__ASM volatile("SVC %0 \n"
"BX LR \n"
: : "I" (TFM_SVC_PSA_WAIT)); }
---
The cause is IACCVIOL, "The processor attempted an instruction fetch from a location that does not permit execution."
The stack frame indicates that it happened on the SVC instruction, but I as far as I can see none of the MPU regions maps the address so I assumed it should be allowed as it should be handled by the background map, which should allow secure access.
If I don't enable the mpu (just skipping the enable call) then all tests run without problems.
I have tried to compare it with an image built with ARMCLANG, and I don't see anything obviously different. The regions are roughly the same, all regions with fixed addresses are the same, the enable bits are the same and the SVC handler is not mapped to any MPU region there either. I wish there were an MPU status register that would tell exactly what region was causing the exception.
The odd thing is that there is an SVC call in the tfm_enable_irq() call prior to the psa_wait() call, and that works.
This is on a Musca A by the way.
Ideas?
--
*Thomas Törnblom*, /Product Engineer/
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
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Hi TFM experts,
I have a question about the code logic of irq handling in library mode, code blocks in spm_api_func.c are as follows:
void tfm_spm_partition_push_interrupted_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct interrupted_ctx_stack_frame_t *stack_frame =
(struct interrupted_ctx_stack_frame_t *)runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
}
void tfm_spm_partition_push_handler_ctx(uint32_t partition_idx)
{
struct spm_partition_runtime_data_t *runtime_data =
&g_spm_partition_db.partitions[partition_idx].runtime_data;
struct handler_ctx_stack_frame_t *stack_frame =
(struct handler_ctx_stack_frame_t *)
runtime_data->ctx_stack_ptr;
stack_frame->partition_state = runtime_data->partition_state;
stack_frame->caller_partition_idx = runtime_data->caller_partition_idx;
runtime_data->ctx_stack_ptr +=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
}
My question is why there is not the following such code logic at the end of function tfm_spm_partition_push_interrupted_ctx.
runtime_data->ctx_stack_ptr +=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
If the interrupted partition is the same as the handler partition, interrupted_ctx_stack_frame_t and handler_ctx_stack_frame_t should be pushed at different location.
And when pop the stack frame after handling irq, there is the following code logic in tfm_spm_partition_pop_handler_ctx
runtime_data->ctx_stack_ptr -=
sizeof(struct handler_ctx_stack_frame_t) / sizeof(uint32_t);
I think the same logic of changing ctx_stack_ptr should be added the begining of the function tfm_spm_partition_pop_interrupted_ctx like the above code logic in tfm_spm_partition_pop_handler_ctx.
runtime_data->ctx_stack_ptr -=
sizeof(struct interrupted_ctx_stack_frame_t ) / sizeof(uint32_t);
Please help to check.
Thanks,
Matt
Hi all,
After several rounds of review, I'd like to merge Cypress PSoC 64 support on master branch this Tuesday.
If you have more comments or opinions, please share them before Tuesday.
Thank you.
Best regards,
Hu Ziji
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Christopher Brand via TF-M
Sent: Saturday, December 7, 2019 4:13 AM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] Adding Cypress PSoC64 platform support
Hi,
I recently pushed patches to add support for a platform based on Cypress' PSoC64 SoC to gerrit.
Given that this is the first non-Arm platform to be posted, it seems worth drawing attention to.
Comments very much appreciated.
I do anticipate a few small updates to the patchset, even in the absence of comments. In particular, there are some documentation improvements to come.
There are four patches in total, ending with https://review.trustedfirmware.org/c/trusted-firmware-m/+/2728https://review.trustedfirmware.org/c/trusted-firmware-m/+/2725/1 adds files to the platform/ext/cmsis directory, and so will affect/be affected by https://review.trustedfirmware.org/c/trusted-firmware-m/+/2578
Thanks,
Chris
This message and any attachments may contain confidential information from Cypress or its subsidiaries. If it has been received in error, please advise the sender and immediately delete this message.
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Hi all,
I'd like to merge the patch set https://review.trustedfirmware.org/q/topic:%22template_plat_files%22+(statu… soon if no further comments.
Please share your comments before this Tuesday.
Best regards,
Hu Ziji
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Hu (Arm Technology China) via TF-M
Sent: Thursday, December 12, 2019 11:57 AM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Please review the patch set to extract duplicated template files from platforms
Hi all,
I submit a patch set to extract the duplicated identical template files dummy_xxx.c from targets and put them under platform/ext/common/template folder.
The purpose is to collect a common template of booting/attestation example for platforms and each platform doesn't need to keep a copy under its folder anymore.
Since it is a general change related to all platforms using template files, I'd like to ask for review here. Any comments would be appreciated.
Please check the patch details in https://review.trustedfirmware.org/q/topic:%22template_plat_files%22+(statu…
The background is described in https://developer.trustedfirmware.org/T539.
Best regards,
Hu Ziji
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The current RTOS integration with TZ API support is to make it generic. You can use "empty" implementation for these API if you don't use multiple secure context (SFC or IPC model) and have no multiple NS client IDs requirements.
Besides that, the users can leverage TZ API for some other purposes, e.g. policy control for which NS task can access which secure partitions and etc. But that's quite use case specific. Just FYI.
Regards,
David Wang
ARM Electronic Technology (Shanghai) Co., Ltd
Phone: +86-21-6154 9142 (ext. 59142)
________________________________
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> on behalf of Reinhard Keil via TF-M <tf-m(a)lists.trustedfirmware.org>
Sent: 13 December 2019 19:41
To: tf-m(a)lists.trustedfirmware.org <tf-m(a)lists.trustedfirmware.org>
Subject: Re: [TF-M] Simplify RTOS / TF-M interface (single thread execution)
Ken,
thanks for all your swift answers.
Sorry, I need to check on this part of the answer again:
* What happens worst case when an RTOS does not implement TZ RTOS Context Management?
Ken.L: If there is no locking protection in NS and multiple ns calling would panic.
TZ RTOS Context Management does not prevent from that. Correct.
So the only feature that is enabled with TZ RTOS Context Management is 'client ID identification' for Protected Storage (and potentially other services).
Reinhard
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Hi,
Hi,
I agree, the CI shall not dictate how we use the version control system. It shall adapt.
Regarding your suggestions, I think the main problem is we are mixing stuff, this time quality with version control. Before we make decisions we shall understand where we are.
The current quality policy is that we only make releases for communication purposes. To give a clean interface for tf-m users and to allow planning their work. Releases allow them to execute their tf-m integration process less frequently. Only for each release or specific releases and not for each commit. The current quality policy identifies a single quality level only, and says any patch we publish is "golden quality", it matches the highest quality standard we can achieve (with sane constraints). Also to make our life easy we decided to use the master branch to hold these patches.
At the same time we use the master branch for development. Any change we make is made against master. This means each pull request and thus each review targets master. For review purposes the best is to have a chain of small modifications, otherwise the review content becomes too large to follow.
The TF-A "branching strategy" tries to address this issue by introducing an integration branch used for development. This allows master to be more release specific.
I suggest to take the following approach (details to be discussed):
- introduce more quality levels i.e.:
- none: content of a topic branch, or content pushed to review.
- bronze: content passed code review and patch specific testing.
- silver: content passed a more though daily testing.
- gold: a release. A pack of source-code, feature state document (release notes), reviewed documentation (user manual, reference manual), test evidence, documentation of test efforts to allow repeatability. The version control system can be used to store content, and to provide identification info (i.e. tagging), but most likely the release will need other kind of storage to be used (i.e. documentation).
- platina: reaching extra quality level trough passing PSA or some FUSA qualification. Or we may simply use extra release for this.
Naming the quality levels allows us to have a cleaner definition of what can be expected at a specific level (set of quality measures, i.e. static analysis, code review, test configuration). It would also allow us cleaner communication and to find how we use the version system for quality purposes.
I also expect this discussion to help defining how the version system is used for development purposes.
The current state works ok, but is a sort of naturally grown. We might have reached the point when more pragmatic approach may be needed.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Minos Galanakis via TF-M
Sent: 13 December 2019 12:23
To: Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>; Soby Mathew <Soby.Mathew(a)arm.com>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi all.
My personal comments on this.
I would like to point out that the CI is a tool, not the core project. I do not believe we should be changing our development strategy based on what the tool is doing. We should instead adjust the tool to fit our requirements.
* No patches should be/ are merged to master when CI fails. If master breaks it should most commonly be because of something we are not testing for. Using an integration branch would not change that.
* As a developer I find it more convoluted to work with projects who use different integration strategies. The most common assumption in open source projects is that you have a master branch which is the bleeding edge, but can contain untested bugs, and the release immutable git tags for versioning. Using branch merges as versioning is a design for the pull request model which is not quite compatible with Gerrit.
* Most of the CI downtime has nothing to do with the merge strategy, they are more of a chicken and the egg philosophical problem. If your patch or branch introduced a change which affects the tests outputs, how will you test it if the CI expects the old output? An integration branch would not solve the merge freeze periods, would just affect a different branch from master.
* I believe feature branches are quite useful, since changes to master do not disrupt the development flow of a big change, and even though they will require some maintenance to re-sync before the final patch , it will be handled by an engineer who knows the feature, and full understands the regression vectors.
If I were to suggest some changes for stability purposes, I would start smaller:
* Update documentation to instruct users to check out from release tags, warning then that master is constantly changing.
* Adjust the CI to detect an Allow-CI flag from every branch. That way developers can test any patch from any feature branch. The logic for that is already present in the code, but requires Gerrit to be configured accordingly.
* Add an undo process. This would be the only case for an integration branch. All patches are merged to a temporary branch, after confirming they have passed testing individually. On the once per day nightly test, the group of different patches, will be tested against an extensive job, in models and hardware, and only if successful it will fast forward master to that state.
Regards
Minos
________________________________
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> on behalf of Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>
Sent: 13 December 2019 08:55
To: Soby Mathew <Soby.Mathew(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Soby,
Thanks for your detail description.
> Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
> This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
I think it's a good method like this so that we can double confirm the "master" branch is stable.
And this also can fix one case even the CI can work normally: one patch is ready to merge, and it is not based on the latest HEAD, but there is no conflict. We can merge the patch directly and let gerrit do rebase by itself. But we cannot confirm the CI test can pass.
Any comment for this from others?
For multiple feature branches, I think we can stop to discuss about it now until we have some strong demands for it. It is indeed a big change for us now.
Thanks,
Edison
-----Original Message-----
From: Soby Mathew <Soby.Mathew(a)arm.com>
Sent: Friday, December 13, 2019 5:14 AM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
On 11/12/2019 09:05, Edison Ai (Arm Technology China) via TF-M wrote:
> Hi Gyorgy,
>
> Thanks to point it out. I agree with you that it will be better if we can align these two projects in this. I had a quick check the branches from TF-A: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/.
> There are three branches in TF-A:
> - "integration" branch, should be used for new features.
> - "master" branch, which is behind of "integration" branch. But I am nor sure what is the strategy to update it.
Hi Edison,
Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
> - "topics/epic_beta0_spmd", I thinks it should like a feature branch for big feature.
> @Soby Mathew Could you help to share more information about it? Thanks very much.
We usually do not have feature branches in TF-A. The topics/epic_beta0_spmd is a prototyping branch where we wanted to share code with collaborators outside TF-A. The patches on this branch are not visible in gerrit review and no patches in gerrit review will be merged to this branch. Once the prototyping is complete, then patches on this branch will be reworked and pushed to gerrit review and finally get merged to integration and this branch will be deleted.
Our experience have been, long running development branches are generally a maintenance overhead. Merging these development branches before a release may also be risky as some of the changes may have unknown interactions and may become difficult to resolve.
The "topic" in gerrit review is effectively a branch. For example, this
review:
https://review.trustedfirmware.org/#/q/topic:od/debugfs+(status:open+OR+sta…
is a set of patches on topic "od/debugfs" and can be treated as development branch. This branch is alive as long as patches are not merged.
We need to understand the motivations for the change. Broken CI is an argument but development branches will only exacerbate that problem since we don't know the stability of each of those branches. Also merge conflict will not reduce due to development branches. Its just delaying the merge conflict to a later point.
There may be other reasons, but generally it is better to merge sensible patches (+2ed) within a feature even before the feature is complete as it will reduce merge conflicts (we have to ensure testing/build coverage for the patch). These are my thoughts on this.
Best Regards
Soby Mathew
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Ken,
thanks for all your swift answers.
Sorry, I need to check on this part of the answer again:
* What happens worst case when an RTOS does not implement TZ RTOS Context Management?
Ken.L: If there is no locking protection in NS and multiple ns calling would panic.
TZ RTOS Context Management does not prevent from that. Correct.
So the only feature that is enabled with TZ RTOS Context Management is 'client ID identification' for Protected Storage (and potentially other services).
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Hi all.
My personal comments on this.
I would like to point out that the CI is a tool, not the core project. I do not believe we should be changing our development strategy based on what the tool is doing. We should instead adjust the tool to fit our requirements.
* No patches should be/ are merged to master when CI fails. If master breaks it should most commonly be because of something we are not testing for. Using an integration branch would not change that.
* As a developer I find it more convoluted to work with projects who use different integration strategies. The most common assumption in open source projects is that you have a master branch which is the bleeding edge, but can contain untested bugs, and the release immutable git tags for versioning. Using branch merges as versioning is a design for the pull request model which is not quite compatible with Gerrit.
* Most of the CI downtime has nothing to do with the merge strategy, they are more of a chicken and the egg philosophical problem. If your patch or branch introduced a change which affects the tests outputs, how will you test it if the CI expects the old output? An integration branch would not solve the merge freeze periods, would just affect a different branch from master.
* I believe feature branches are quite useful, since changes to master do not disrupt the development flow of a big change, and even though they will require some maintenance to re-sync before the final patch , it will be handled by an engineer who knows the feature, and full understands the regression vectors.
If I were to suggest some changes for stability purposes, I would start smaller:
* Update documentation to instruct users to check out from release tags, warning then that master is constantly changing.
* Adjust the CI to detect an Allow-CI flag from every branch. That way developers can test any patch from any feature branch. The logic for that is already present in the code, but requires Gerrit to be configured accordingly.
* Add an undo process. This would be the only case for an integration branch. All patches are merged to a temporary branch, after confirming they have passed testing individually. On the once per day nightly test, the group of different patches, will be tested against an extensive job, in models and hardware, and only if successful it will fast forward master to that state.
Regards
Minos
________________________________
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> on behalf of Edison Ai (Arm Technology China) via TF-M <tf-m(a)lists.trustedfirmware.org>
Sent: 13 December 2019 08:55
To: Soby Mathew <Soby.Mathew(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Soby,
Thanks for your detail description.
> Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
> This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
I think it's a good method like this so that we can double confirm the "master" branch is stable.
And this also can fix one case even the CI can work normally: one patch is ready to merge, and it is not based on the latest HEAD, but there is no conflict. We can merge the patch directly and let gerrit do rebase by itself. But we cannot confirm the CI test can pass.
Any comment for this from others?
For multiple feature branches, I think we can stop to discuss about it now until we have some strong demands for it. It is indeed a big change for us now.
Thanks,
Edison
-----Original Message-----
From: Soby Mathew <Soby.Mathew(a)arm.com>
Sent: Friday, December 13, 2019 5:14 AM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
On 11/12/2019 09:05, Edison Ai (Arm Technology China) via TF-M wrote:
> Hi Gyorgy,
>
> Thanks to point it out. I agree with you that it will be better if we can align these two projects in this. I had a quick check the branches from TF-A: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/.
> There are three branches in TF-A:
> - "integration" branch, should be used for new features.
> - "master" branch, which is behind of "integration" branch. But I am nor sure what is the strategy to update it.
Hi Edison,
Integration is a temporary merge branch to merge several patches and run the CI against. Usually once CI passes, the master will be fast forwarded to integration within a day.
This helps us to test integration of patches and detect any failure before master is updated. This means the master will pass CI at any given merge point.
> - "topics/epic_beta0_spmd", I thinks it should like a feature branch for big feature.
> @Soby Mathew Could you help to share more information about it? Thanks very much.
We usually do not have feature branches in TF-A. The topics/epic_beta0_spmd is a prototyping branch where we wanted to share code with collaborators outside TF-A. The patches on this branch are not visible in gerrit review and no patches in gerrit review will be merged to this branch. Once the prototyping is complete, then patches on this branch will be reworked and pushed to gerrit review and finally get merged to integration and this branch will be deleted.
Our experience have been, long running development branches are generally a maintenance overhead. Merging these development branches before a release may also be risky as some of the changes may have unknown interactions and may become difficult to resolve.
The "topic" in gerrit review is effectively a branch. For example, this
review:
https://review.trustedfirmware.org/#/q/topic:od/debugfs+(status:open+OR+sta…
is a set of patches on topic "od/debugfs" and can be treated as development branch. This branch is alive as long as patches are not merged.
We need to understand the motivations for the change. Broken CI is an argument but development branches will only exacerbate that problem since we don't know the stability of each of those branches. Also merge conflict will not reduce due to development branches. Its just delaying the merge conflict to a later point.
There may be other reasons, but generally it is better to merge sensible patches (+2ed) within a feature even before the feature is complete as it will reduce merge conflicts (we have to ensure testing/build coverage for the patch). These are my thoughts on this.
Best Regards
Soby Mathew
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Ken,
Thanks for your reply. Let me summarize what I have understood:
TF-M SFC mode:
* Allows only one thread at the time to call secure services.
* When secure services are called recursively (multiple threads) TF-M goes into 'panic' state. This should not happen with proper mutex locks.
* TZ RTOS Context Management interface is only required when "Client Oriented Policy" is used.
I have updated the diagram to reflect what I have understood. Obviously the SVC would be only executed when the call into "secure" is from Thread mode. Is my understanding correct? (diagram is also under: https://developer.trustedfirmware.org/T615) - I just realized that you made a similar picture).
[cid:image003.jpg@01D5B197.BE352670]
The initial question can be then refined to:
* TZ RTOS Context management is only needed when "Client Oriented Policy" is used.
* When and why is "Client Oriented Policy" a requirement on v8-M systems?
* Is there a way to disable ""Client Oriented Policy" in the current TF-M Core?
* This applies for both the TF-M firmware itself and the related test suite.
* What happens worst case when an RTOS does not implement TZ RTOS Context Management?
Reinhard
_______________________________________________________________________________
Reinhard Keil | Phone: +49 89 456040-13 | Email: reinhard.keil(a)arm.com<mailto:reinhard.keil@arm.com> | www.keil.com<http://www.keil.com>
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Hi Matt,
Thanks for your quick patch.
Hi All,
The patch link is here: https://review.trustedfirmware.org/#/c/trusted-firmware-m/+/2792/. Please help to review it if you are interested.
Thanks,
Edison
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Thursday, December 12, 2019 4:42 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] Secure storage and Internal trusted storage code logic check
Hi Edison,
Thanks for your quick reply. I will try to upstream a patch later.
Thanks,
Matt
At 2019-12-12 11:15:51, "Edison Ai \\(Arm Technology China\\) via TF-M" <tf-m(a)lists.trustedfirmware.org> wrote:
>Hi Matt,
>
>Thanks very much for your mail. It looks like it is indeed a problem here.
>Can you upstream a patch to help to fix them directly?
>
>Thanks,
>Edison
>
>-----Original Message-----
>From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
>Sent: Thursday, December 12, 2019 9:43 AM
>To: tf-m(a)lists.trustedfirmware.org
>Subject: [TF-M] Secure storage and Internal trusted storage code logic check
>
>Hi TFM Secure storage & Internal trusted storage experts,
>
>
> It seems there are code logic errors in both files sst_flash_fs_mblock.c and its_flash_fs_mblock.c.
> There are following codes in function its_flash_fs_mblock_reset_metablock in its_flash_fs_mblock.c:
>
>
> for (i = ITS_INIT_DBLOCK_START; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
> /* If a flash error is detected, the code erases the rest
> * of the blocks anyway to remove all data stored in them.
> */
> err |= its_flash_erase_block(i);
> }
> This loop starts from ITS_INIT_DBLOCK_START and ends to ITS_NUM_DEDICATED_DBLOCKS.
> If there are four ITS blocks including meta blocks and data blocks in all, that means ITS_INIT_DBLOCK_START
> is 3 and ITS_NUM_DEDICATED_DBLOCKS is 1. But the above loop can not erase the data block any way.
> Should it be the following logic?
>
>
> for (i = 0; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
> /* If a flash error is detected, the code erases the rest
> * of the blocks anyway to remove all data stored in them.
> */
> err |= its_flash_erase_block(i+ITS_INIT_DBLOCK_START);
> }
> It is the same logic in function sst_flash_fs_mblock_reset_metablock in file sst_flash_fs_mblock.c.
>
>
> Please help to check.
>
>
>Thanks.
>Matt.
>
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On 11/12/2019 09:05, Edison Ai (Arm Technology China) via TF-M wrote:
> Hi Gyorgy,
>
> Thanks to point it out. I agree with you that it will be better if we can align these two projects in this. I had a quick check the branches from TF-A: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/.
> There are three branches in TF-A:
> - "integration" branch, should be used for new features.
> - "master" branch, which is behind of "integration" branch. But I am nor sure what is the strategy to update it.
Hi Edison,
Integration is a temporary merge branch to merge several patches and run
the CI against. Usually once CI passes, the master will be fast
forwarded to integration within a day.
This helps us to test integration of patches and detect any failure
before master is updated. This means the master will pass CI at any
given merge point.
> - "topics/epic_beta0_spmd", I thinks it should like a feature branch for big feature.
> @Soby Mathew Could you help to share more information about it? Thanks very much.
We usually do not have feature branches in TF-A. The
topics/epic_beta0_spmd is a prototyping branch where we wanted to share
code with collaborators outside TF-A. The patches on this branch are not
visible in gerrit review and no patches in gerrit review will be merged
to this branch. Once the prototyping is complete, then patches on this
branch will be reworked and pushed to gerrit review and finally get
merged to integration and this branch will be deleted.
Our experience have been, long running development branches are
generally a maintenance overhead. Merging these development branches
before a release may also be risky as some of the changes may have
unknown interactions and may become difficult to resolve.
The "topic" in gerrit review is effectively a branch. For example, this
review:
https://review.trustedfirmware.org/#/q/topic:od/debugfs+(status:open+OR+sta…
is a set of patches on topic "od/debugfs" and can be treated as
development branch. This branch is alive as long as patches are not merged.
We need to understand the motivations for the change. Broken CI is an
argument but development branches will only exacerbate that problem
since we don't know the stability of each of those branches. Also merge
conflict will not reduce due to development branches. Its just delaying
the merge conflict to a later point.
There may be other reasons, but generally it is better to merge sensible
patches (+2ed) within a feature even before the feature is complete as
it will reduce merge conflicts (we have to ensure testing/build coverage
for the patch). These are my thoughts on this.
Best Regards
Soby Mathew
Hi Reinhard,
Guess this diagram for a long time ago design since the latest version there is no need for NS SVC. (Check diagram attached in the ticket).
I think the existing library model implementation is almost the one you described, just some points:
- We use a secure SVC in SPM for sanitization input/output buffers.
- We do secure partition maintenance in SPM (forward call, maintain state).
The TZ API implementation under SFC is for the purpose that some services have bound the client with policies so they need to know which client is calling. It can be skipped if there is no such client-orient policy.
And one thing to mention, even we propose to use locks in RTOS for locking the interface, there would be a chance that some RTOS has a limitation on these lock APIs, or someone just acts as an attacker who skips the necessary locking operations, then we need to provide some detection in the secure side as countermeasures, and this part needs to be documented to remind users that, please make sure there is only one ongoing secure call or a panic is generated. Then it would be RTOS' choice to decide if they want to avoid this panic by locking.
/Ken
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: Thursday, December 12, 2019 11:22 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] Simplify RTOS / TF-M interface (single thread execution)
As the picture got lost, I did create also https://developer.trustedfirmware.org/T615
This contains the picture
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
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Next issue.
For some reason the secure image runs into a MemManage exception fairly
early in the irq test of the ConfigRegressionIPCTfmLevel2 config and I
have not yet been able to figure out why.
It happens in the psa_wait() call in:
---
int32_t tfm_irq_test_1_init(void)
{
tfm_enable_irq(SPM_CORE_IRQ_TEST_1_SIGNAL_TIMER_0_IRQ);
#ifdef TFM_PSA_API
psa_signal_t signals = 0;
while (1) {
signals = psa_wait(PSA_WAIT_ANY, PSA_BLOCK);
---
The exact point of the exception is the SVC call in:
---
__attribute__((naked, section("SFN")))
psa_signal_t psa_wait(psa_signal_t signal_mask, uint32_t timeout)
{
__ASM volatile("SVC %0 \n"
"BX LR \n"
: : "I" (TFM_SVC_PSA_WAIT));
}
---
The cause is IACCVIOL, "The processor attempted an instruction fetch
from a location that does not permit execution."
The stack frame indicates that it happened on the SVC instruction, but I
as far as I can see none of the MPU regions maps the address so I
assumed it should be allowed as it should be handled by the background
map, which should allow secure access.
If I don't enable the mpu (just skipping the enable call) then all tests
run without problems.
I have tried to compare it with an image built with ARMCLANG, and I
don't see anything obviously different. The regions are roughly the
same, all regions with fixed addresses are the same, the enable bits are
the same and the SVC handler is not mapped to any MPU region there
either. I wish there were an MPU status register that would tell exactly
what region was causing the exception.
The odd thing is that there is an SVC call in the tfm_enable_irq() call
prior to the psa_wait() call, and that works.
This is on a Musca A by the way.
Ideas?
--
*Thomas Törnblom*, /Product Engineer/
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
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Hello,
To continuing our open discussion, started a week ago let me propose the 2nd session and create this mail thread to discuss related topics.
1. The time slot.
Looking on participants' distribution [Asia:6, Europe:20, US East:1, US Cent:1, US West:4, Total:32] I see the majority is in Europe. The Asian region could be more presented giving a more comfortable time. Having this in mind, I would propose to have the 2nd session on Dec 19 at 7:00 UTC time. This compromise gives US West coast a chance to join at 23:00 (Dec 18!). Here is the summary:
https://www.timeanddate.com/worldclock/meetingdetails.html?year=2019&month=…
Please share your thoughts and alternatives. The related question: shall we fix the time or rotating?
You can play with the time slot here:
https://www.timeanddate.com/worldclock/meetingtime.html?day=19&month=12&yea…
2. Agenda as a proposal
- The interrupts' topic was followed by email and looks like closed. Are there remaining points for discussion?
- TF-M and Amazon FreeRTOS integration update
- Cryptocell integration
- ?
Best regards,
Anton Komlev
Hi,
Sorry the image did not got trough. One way to share the image could be to create a ticket here https://developer.trustedfirmware.org/maniphest/ where the image can be uploaded.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Reinhard Keil via TF-M
Sent: 12 December 2019 13:13
To: tf-m(a)lists.trustedfirmware.org
Cc: Bruno Mendes <Bruno.Mendes(a)arm.com>
Subject: [TF-M] Simplify RTOS / TF-M interface (single thread execution)
When using TF-M on v8-M with Secure Function Call SFC (aka Library) mode, the entry to the secure side is protected by a Mutex.
Thus only one thread at the time is calling a secure service. The picture below should therefore represent the execution flow (Level 1 isolation).
[cid:image003.jpg@01D5B0ED.DEEA6A60]
Under this assumption there is no need to implement TZ_context management in the RTOS (https://arm-software.github.io/CMSIS_5/Core/html/using_TrustZone_pg.html#RT…). Any RTOS could be used, provided that the Mutex capability is sufficient.
Moreover this design should create a really simple secure side:
* Only one stack is needed on the secure side for Thread mode execution
* No multi-threading issues that need to be resolved (i.e. with access of hardware crypto accelerators)
The drawback of course is that only one task at a time can use a secure service. However an RTOS with priority inversion will ensure that the Secure service is executed as fast as possible, once a scheduling conflict arises.
I would like to gather feedback on that approach. Let me know what you think.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
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When using TF-M on v8-M with Secure Function Call SFC (aka Library) mode, the entry to the secure side is protected by a Mutex.
Thus only one thread at the time is calling a secure service. The picture below should therefore represent the execution flow (Level 1 isolation).
[cid:image003.jpg@01D5B0ED.DEEA6A60]
Under this assumption there is no need to implement TZ_context management in the RTOS (https://arm-software.github.io/CMSIS_5/Core/html/using_TrustZone_pg.html#RT…). Any RTOS could be used, provided that the Mutex capability is sufficient.
Moreover this design should create a really simple secure side:
* Only one stack is needed on the secure side for Thread mode execution
* No multi-threading issues that need to be resolved (i.e. with access of hardware crypto accelerators)
The drawback of course is that only one task at a time can use a secure service. However an RTOS with priority inversion will ensure that the Secure service is executed as fast as possible, once a scheduling conflict arises.
I would like to gather feedback on that approach. Let me know what you think.
Reinhard
IMPORTANT NOTICE: The contents of this email and any attachments are confidential and may also be privileged. If you are not the intended recipient, please notify the sender immediately and do not disclose the contents to any other person, use it for any purpose, or store or copy the information in any medium. Thank you.
Ken,
Task scheduling (context switching) in our RTOS is always performed in thread mode, even when asynchronous pre-emption occurs resulting from an ISR readying a higher priority task.
All kernel-managed interrupts are routed to a common interrupt dispatcher that, just prior to returning from an interrupt, will invoke the task scheduler when it determines that there are no more interrupts pending and there is scheduling work to do. In that case, an artificial interrupt context is created so that thread mode can be "returned to" from handler mode. The task scheduler is then invoked in thread mode from the stack of the pre-empted task.
Regarding secure interrupts, our use cases only employ secure interrupts as a consequence of a psa_call() initiating a process that completes when an interrupt goes off sometime later.
Rather than spin-waiting for the interrupt-completion signal, or parking in a WFI, we simply return from the psa_call() with a special return code indicating that the process has started and that the calling thread will be notified of completion by the secure callback mechanism I described at the conference in Lyon. The calling thread then pends on a semaphore. When the secure interrupt goes off later on, a dedicated non-secure interrupt is triggered that ultimately ends up posting the semaphore that the NS thread is pended on. Upon returning from the pend, the NS thread then re-enters the SP (using psa_call()) to complete the transaction.
Alan
-----Original Message-----
From: TF-M [mailto:tf-m-bounces@lists.trustedfirmware.org] On Behalf Of Ken Liu (Arm Technology China) via TF-M
Sent: Tuesday, December 10, 2019 8:04 PM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd
Subject: [EXTERNAL] [TF-M] Secure Interrupt handling - RE: TF-M technical Forum slides and recording
Thank Bill for updating this.
I want to use this thread to follow up on the topic 'secure interrupt' given in the 1st tech forum.
That is a prologue of the scheduler and interrupt designs. And I do see there are some use cases that I did not focus on, so I want to collect more user scenarios first, and then try to enhance the drafting design (will be published after I updated it base on your inputs).
About the secure interrupt usage:
- A secure interrupt would be introduced by a secure service call in general; is there any scenarios that there would be an interval secure interrupt since secure service want to do something? For example, a secure timer triggers to let secure service has the chance to do things in the background (not for an ongoing secure call from NSPE) after a period of time?
And the question about the system Alan mentioned, just want to confirm if it is a pure thread mode scheduling system? How does the system handle interrupts?
Thanks.
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Bill Fletcher via TF-M
Sent: Monday, December 9, 2019 7:57 PM
To: TF-M mailing list <tf-m(a)lists.trustedfirmware.org>
Subject: [TF-M] TF-M technical Forum slides and recording
Hi all,
I've posted links to the (updated) slide deck and a recording of the call on the meetings page of the Trusted Firmware website:
https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Regards
Bill
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Hi Edison,
Thanks for your quick reply. I will try to upstream a patch later.
Thanks,
Matt
At 2019-12-12 11:15:51, "Edison Ai \\(Arm Technology China\\) via TF-M" <tf-m(a)lists.trustedfirmware.org> wrote:
>Hi Matt,
>
>Thanks very much for your mail. It looks like it is indeed a problem here.
>Can you upstream a patch to help to fix them directly?
>
>Thanks,
>Edison
>
>-----Original Message-----
>From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
>Sent: Thursday, December 12, 2019 9:43 AM
>To: tf-m(a)lists.trustedfirmware.org
>Subject: [TF-M] Secure storage and Internal trusted storage code logic check
>
>Hi TFM Secure storage & Internal trusted storage experts,
>
>
> It seems there are code logic errors in both files sst_flash_fs_mblock.c and its_flash_fs_mblock.c.
> There are following codes in function its_flash_fs_mblock_reset_metablock in its_flash_fs_mblock.c:
>
>
> for (i = ITS_INIT_DBLOCK_START; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
> /* If a flash error is detected, the code erases the rest
> * of the blocks anyway to remove all data stored in them.
> */
> err |= its_flash_erase_block(i);
> }
> This loop starts from ITS_INIT_DBLOCK_START and ends to ITS_NUM_DEDICATED_DBLOCKS.
> If there are four ITS blocks including meta blocks and data blocks in all, that means ITS_INIT_DBLOCK_START
> is 3 and ITS_NUM_DEDICATED_DBLOCKS is 1. But the above loop can not erase the data block any way.
> Should it be the following logic?
>
>
> for (i = 0; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
> /* If a flash error is detected, the code erases the rest
> * of the blocks anyway to remove all data stored in them.
> */
> err |= its_flash_erase_block(i+ITS_INIT_DBLOCK_START);
> }
> It is the same logic in function sst_flash_fs_mblock_reset_metablock in file sst_flash_fs_mblock.c.
>
>
> Please help to check.
>
>
>Thanks.
>Matt.
>
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Hi all,
I submit a patch set to extract the duplicated identical template files dummy_xxx.c from targets and put them under platform/ext/common/template folder.
The purpose is to collect a common template of booting/attestation example for platforms and each platform doesn't need to keep a copy under its folder anymore.
Since it is a general change related to all platforms using template files, I'd like to ask for review here. Any comments would be appreciated.
Please check the patch details in https://review.trustedfirmware.org/q/topic:%22template_plat_files%22+(statu…
The background is described in https://developer.trustedfirmware.org/T539.
Best regards,
Hu Ziji
Hi Matt,
Thanks very much for your mail. It looks like it is indeed a problem here.
Can you upstream a patch to help to fix them directly?
Thanks,
Edison
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of lg via TF-M
Sent: Thursday, December 12, 2019 9:43 AM
To: tf-m(a)lists.trustedfirmware.org
Subject: [TF-M] Secure storage and Internal trusted storage code logic check
Hi TFM Secure storage & Internal trusted storage experts,
It seems there are code logic errors in both files sst_flash_fs_mblock.c and its_flash_fs_mblock.c.
There are following codes in function its_flash_fs_mblock_reset_metablock in its_flash_fs_mblock.c:
for (i = ITS_INIT_DBLOCK_START; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
/* If a flash error is detected, the code erases the rest
* of the blocks anyway to remove all data stored in them.
*/
err |= its_flash_erase_block(i);
}
This loop starts from ITS_INIT_DBLOCK_START and ends to ITS_NUM_DEDICATED_DBLOCKS.
If there are four ITS blocks including meta blocks and data blocks in all, that means ITS_INIT_DBLOCK_START
is 3 and ITS_NUM_DEDICATED_DBLOCKS is 1. But the above loop can not erase the data block any way.
Should it be the following logic?
for (i = 0; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
/* If a flash error is detected, the code erases the rest
* of the blocks anyway to remove all data stored in them.
*/
err |= its_flash_erase_block(i+ITS_INIT_DBLOCK_START);
}
It is the same logic in function sst_flash_fs_mblock_reset_metablock in file sst_flash_fs_mblock.c.
Please help to check.
Thanks.
Matt.
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Hi TFM Secure storage & Internal trusted storage experts,
It seems there are code logic errors in both files sst_flash_fs_mblock.c and its_flash_fs_mblock.c.
There are following codes in function its_flash_fs_mblock_reset_metablock in its_flash_fs_mblock.c:
for (i = ITS_INIT_DBLOCK_START; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
/* If a flash error is detected, the code erases the rest
* of the blocks anyway to remove all data stored in them.
*/
err |= its_flash_erase_block(i);
}
This loop starts from ITS_INIT_DBLOCK_START and ends to ITS_NUM_DEDICATED_DBLOCKS.
If there are four ITS blocks including meta blocks and data blocks in all, that means ITS_INIT_DBLOCK_START
is 3 and ITS_NUM_DEDICATED_DBLOCKS is 1. But the above loop can not erase the data block any way.
Should it be the following logic?
for (i = 0; i < ITS_NUM_DEDICATED_DBLOCKS; i++) {
/* If a flash error is detected, the code erases the rest
* of the blocks anyway to remove all data stored in them.
*/
err |= its_flash_erase_block(i+ITS_INIT_DBLOCK_START);
}
It is the same logic in function sst_flash_fs_mblock_reset_metablock in file sst_flash_fs_mblock.c.
Please help to check.
Thanks.
Matt.
Thanks Thomas.
Let me try that link.
/Ken
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Thomas Törnblom via TF-M
Sent: Wednesday, December 11, 2019 9:13 PM
To: tf-m(a)lists.trustedfirmware.org
Subject: Re: [TF-M] IAR libc behavior?
Hi Ken,
There should be no difference from GNUARM or ARMCLANG in this respect.
Should not need any special switches.
If you wish to try out our tools, you can download a trial version until we have arranged for a permanent solution, see:
https://www.iar.com/iar-embedded-workbench/#!?architecture=Arm
Cheers,
Thomas
Den 2019-12-11 kl. 11:05, skrev Ken Liu (Arm Technology China) via TF-M:
> Hi Thomas,
>
> I have a question about IAR compiler since we verify default GNUARM and ARMCLANG in the existing sources.
> If we are trying to implementing some internal version of libc APIs like 'memcmp', would IAR link with this implemented version first, or it just report a link error of duplicated symbol? Any switches do we need to assign to support this?
>
> Thanks.
>
> /Ken
--
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Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
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Hi Ken,
There should be no difference from GNUARM or ARMCLANG in this respect.
Should not need any special switches.
If you wish to try out our tools, you can download a trial version until
we have arranged for a permanent solution, see:
https://www.iar.com/iar-embedded-workbench/#!?architecture=Arm
Cheers,
Thomas
Den 2019-12-11 kl. 11:05, skrev Ken Liu (Arm Technology China) via TF-M:
> Hi Thomas,
>
> I have a question about IAR compiler since we verify default GNUARM and ARMCLANG in the existing sources.
> If we are trying to implementing some internal version of libc APIs like 'memcmp', would IAR link with this implemented version first, or it just report a link error of duplicated symbol? Any switches do we need to assign to support this?
>
> Thanks.
>
> /Ken
--
*Thomas Törnblom*, /Product Engineer/
IAR Systems AB
Box 23051, Strandbodgatan 1
SE-750 23 Uppsala, SWEDEN
Mobile: +46 76 180 17 80 Fax: +46 18 16 78 01
E-mail: thomas.tornblom(a)iar.com <mailto:thomas.tornblom@iar.com>
Website: www.iar.com <http://www.iar.com>
Twitter: www.twitter.com/iarsystems <http://www.twitter.com/iarsystems>
Hi Thomas,
I have a question about IAR compiler since we verify default GNUARM and ARMCLANG in the existing sources.
If we are trying to implementing some internal version of libc APIs like 'memcmp', would IAR link with this implemented version first, or it just report a link error of duplicated symbol? Any switches do we need to assign to support this?
Thanks.
/Ken
Hi Gyorgy,
Thanks to point it out. I agree with you that it will be better if we can align these two projects in this. I had a quick check the branches from TF-A: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/.
There are three branches in TF-A:
- "integration" branch, should be used for new features.
- "master" branch, which is behind of "integration" branch. But I am nor sure what is the strategy to update it.
- "topics/epic_beta0_spmd", I thinks it should like a feature branch for big feature.
@Soby Mathew Could you help to share more information about it? Thanks very much.
Hi David W,
Thanks for your comments.
For your first comment, I will say yes. Sorry to give the CI problem as a reason.
For your second comment, I think we can use " git merge <commit-id>" to merge up to a special commit of dev to the master branch. In this, we do not need to freeze the patch merging. Maybe other methods to do it. Sorry, I am not a git expert, please correct me if it is wrong.
I agree with you that we need to think clearly about it.
Thanks,
Edison
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Gyorgy Szing via TF-M
Sent: Wednesday, December 11, 2019 3:58 PM
To: David Wang (Arm Technology China) <David.Wang(a)arm.com>; tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi,
Please sync up with the TF-A team on branching strategy. It would be preferred to keep the two projects aligned if possible.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Wang (Arm Technology China) via TF-M
Sent: 11 December 2019 07:59
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Edison,
It sounds reasonable to evolve the branch management in TF-M because we get more and more contributions in the community. Thanks for raising that.
A few comments:
>> * Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
This reason of creating dev branch seems like a workaround as CI is not stable.
>> * We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
If we don’t have the feature branches you proposed, then the problem seems to be the same. It's because dev branch is acting as the master branch and the release(master) branch get "git fast-forward" to a point of dev branch when doing the release. Then we still can't stop merging the unnecessary patches in the release unless we do manual rebase which is not what we wanted.
For feature branches, I think it's a good idea but we need to make a process/policy about how/when to create the branches, who maintain the branches and the timing of merging this feature. This could align with the roadmap and release plan, e.g. next release will include a few features/bugfixes which are in corresponding branches.
Just share my thoughts.
Regards,
David Wang
Arm Electronic Technology (Shanghai) Co., Ltd
Phone: +86-21-6154 9142 (ext. 59142)
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 2:16 PM
To: Kevin Peng (Arm Technology China) <Kevin.Peng(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Kevin,
Yes, you are right. The main point does not break a stable branch, it could be the "master" branch or "release" branch. Your suggest is good for it will not conflict with our current patches(upstream to the master branch). But the users may be more like to fetch code from the master branch for a stable version. We can discuss more about it.
For this, I think we should discuss if it is necessary to create another branch for release or the stable version firstly.
And for "are we already using feature branches such as feature-twincpu?":
Yes, you are right again. But current, only several branches are created for huge features. What I mean it that we should not to merge patch to "master" or "release" branch directly. Or we just merge little change patches to master branch. For others, we can create a dedicated feature branch. For example, PSA FF alignment or even a bug fix.
Thanks,
Edison
-----Original Message-----
From: Kevin Peng (Arm Technology China) <Kevin.Peng(a)arm.com>
Sent: Wednesday, December 11, 2019 1:43 PM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: RE: Create another branch for feature development
Hi Edison,
In your proposal, the new "develop" branch seems to be the current "master" branch and the "master" branch becomes kind of release branch if I'm understand correctly.
So why not create a "release" branch instead.
And are we already using feature branches such as feature-twincpu?
Best Regards,
Kevin
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 11:24 AM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Create another branch for feature development
Hi all,
I have a proposal to create a "develop"(or something like this) branch in TF-M for our feature development. The reasons for this are:
* Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
* We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
More addition, we can create more branches for big features development, such as "develop/feature_a" or "develop/feature_b". All these new features branch need to be merged to the "develop" branch first and then release to the "master" branch.
This is different from the current patch upstream mode, and it needs to spend more time maintaining those branches. But I think it is more convenient for us to develop different features. We do not need to spend more time to fix the conflicts and to do rebase when other patches merge to master branch during patch reviewing.
Welcome to comment on this.
Thanks,
Edison
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Hi all,
I uploaded a hotfix to fix a issue in GNUARM linker script.
https://review.trustedfirmware.org/c/trusted-firmware-m/+/2767
The XXX_ATTR_FN label is named as XXX_LD_ATTR_FN for Application RoT Secure Partitions in GNUARM linker script. Thus GNUARM cannot get the dedicated section address to place the XXX_ATTR_FN section defined in the source code.
It may cause linking error and crash during running.
Please help review the patch. Any comment is welcome and will speed up the fix.
Thank you.
Best regards,
Hu Ziji
Hi,
Please sync up with the TF-A team on branching strategy. It would be preferred to keep the two projects aligned if possible.
/George
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of David Wang (Arm Technology China) via TF-M
Sent: 11 December 2019 07:59
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Edison,
It sounds reasonable to evolve the branch management in TF-M because we get more and more contributions in the community. Thanks for raising that.
A few comments:
>> * Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
This reason of creating dev branch seems like a workaround as CI is not stable.
>> * We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
If we don’t have the feature branches you proposed, then the problem seems to be the same. It's because dev branch is acting as the master branch and the release(master) branch get "git fast-forward" to a point of dev branch when doing the release. Then we still can't stop merging the unnecessary patches in the release unless we do manual rebase which is not what we wanted.
For feature branches, I think it's a good idea but we need to make a process/policy about how/when to create the branches, who maintain the branches and the timing of merging this feature. This could align with the roadmap and release plan, e.g. next release will include a few features/bugfixes which are in corresponding branches.
Just share my thoughts.
Regards,
David Wang
Arm Electronic Technology (Shanghai) Co., Ltd
Phone: +86-21-6154 9142 (ext. 59142)
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 2:16 PM
To: Kevin Peng (Arm Technology China) <Kevin.Peng(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Kevin,
Yes, you are right. The main point does not break a stable branch, it could be the "master" branch or "release" branch. Your suggest is good for it will not conflict with our current patches(upstream to the master branch). But the users may be more like to fetch code from the master branch for a stable version. We can discuss more about it.
For this, I think we should discuss if it is necessary to create another branch for release or the stable version firstly.
And for "are we already using feature branches such as feature-twincpu?":
Yes, you are right again. But current, only several branches are created for huge features. What I mean it that we should not to merge patch to "master" or "release" branch directly. Or we just merge little change patches to master branch. For others, we can create a dedicated feature branch. For example, PSA FF alignment or even a bug fix.
Thanks,
Edison
-----Original Message-----
From: Kevin Peng (Arm Technology China) <Kevin.Peng(a)arm.com>
Sent: Wednesday, December 11, 2019 1:43 PM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: RE: Create another branch for feature development
Hi Edison,
In your proposal, the new "develop" branch seems to be the current "master" branch and the "master" branch becomes kind of release branch if I'm understand correctly.
So why not create a "release" branch instead.
And are we already using feature branches such as feature-twincpu?
Best Regards,
Kevin
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 11:24 AM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Create another branch for feature development
Hi all,
I have a proposal to create a "develop"(or something like this) branch in TF-M for our feature development. The reasons for this are:
* Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
* We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
More addition, we can create more branches for big features development, such as "develop/feature_a" or "develop/feature_b". All these new features branch need to be merged to the "develop" branch first and then release to the "master" branch.
This is different from the current patch upstream mode, and it needs to spend more time maintaining those branches. But I think it is more convenient for us to develop different features. We do not need to spend more time to fix the conflicts and to do rebase when other patches merge to master branch during patch reviewing.
Welcome to comment on this.
Thanks,
Edison
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Hi Edison,
It sounds reasonable to evolve the branch management in TF-M because we get more and more contributions in the community. Thanks for raising that.
A few comments:
>> * Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
This reason of creating dev branch seems like a workaround as CI is not stable.
>> * We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
If we don’t have the feature branches you proposed, then the problem seems to be the same. It's because dev branch is acting as the master branch and the release(master) branch get "git fast-forward" to a point of dev branch when doing the release. Then we still can't stop merging the unnecessary patches in the release unless we do manual rebase which is not what we wanted.
For feature branches, I think it's a good idea but we need to make a process/policy about how/when to create the branches, who maintain the branches and the timing of merging this feature. This could align with the roadmap and release plan, e.g. next release will include a few features/bugfixes which are in corresponding branches.
Just share my thoughts.
Regards,
David Wang
Arm Electronic Technology (Shanghai) Co., Ltd
Phone: +86-21-6154 9142 (ext. 59142)
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 2:16 PM
To: Kevin Peng (Arm Technology China) <Kevin.Peng(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: Re: [TF-M] Create another branch for feature development
Hi Kevin,
Yes, you are right. The main point does not break a stable branch, it could be the "master" branch or "release" branch. Your suggest is good for it will not conflict with our current patches(upstream to the master branch). But the users may be more like to fetch code from the master branch for a stable version. We can discuss more about it.
For this, I think we should discuss if it is necessary to create another branch for release or the stable version firstly.
And for "are we already using feature branches such as feature-twincpu?":
Yes, you are right again. But current, only several branches are created for huge features. What I mean it that we should not to merge patch to "master" or "release" branch directly. Or we just merge little change patches to master branch. For others, we can create a dedicated feature branch. For example, PSA FF alignment or even a bug fix.
Thanks,
Edison
-----Original Message-----
From: Kevin Peng (Arm Technology China) <Kevin.Peng(a)arm.com>
Sent: Wednesday, December 11, 2019 1:43 PM
To: Edison Ai (Arm Technology China) <Edison.Ai(a)arm.com>; 'tf-m(a)lists.trustedfirmware.org' <tf-m(a)lists.trustedfirmware.org>
Cc: nd <nd(a)arm.com>
Subject: RE: Create another branch for feature development
Hi Edison,
In your proposal, the new "develop" branch seems to be the current "master" branch and the "master" branch becomes kind of release branch if I'm understand correctly.
So why not create a "release" branch instead.
And are we already using feature branches such as feature-twincpu?
Best Regards,
Kevin
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 11:24 AM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Create another branch for feature development
Hi all,
I have a proposal to create a "develop"(or something like this) branch in TF-M for our feature development. The reasons for this are:
* Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
* We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
More addition, we can create more branches for big features development, such as "develop/feature_a" or "develop/feature_b". All these new features branch need to be merged to the "develop" branch first and then release to the "master" branch.
This is different from the current patch upstream mode, and it needs to spend more time maintaining those branches. But I think it is more convenient for us to develop different features. We do not need to spend more time to fix the conflicts and to do rebase when other patches merge to master branch during patch reviewing.
Welcome to comment on this.
Thanks,
Edison
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Hi Edison,
In your proposal, the new "develop" branch seems to be the current "master" branch and the "master" branch becomes kind of release branch if I'm understand correctly.
So why not create a "release" branch instead.
And are we already using feature branches such as feature-twincpu?
Best Regards,
Kevin
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Edison Ai (Arm Technology China) via TF-M
Sent: Wednesday, December 11, 2019 11:24 AM
To: tf-m(a)lists.trustedfirmware.org
Cc: nd <nd(a)arm.com>
Subject: [TF-M] Create another branch for feature development
Hi all,
I have a proposal to create a "develop"(or something like this) branch in TF-M for our feature development. The reasons for this are:
* Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
* We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
More addition, we can create more branches for big features development, such as "develop/feature_a" or "develop/feature_b". All these new features branch need to be merged to the "develop" branch first and then release to the "master" branch.
This is different from the current patch upstream mode, and it needs to spend more time maintaining those branches. But I think it is more convenient for us to develop different features. We do not need to spend more time to fix the conflicts and to do rebase when other patches merge to master branch during patch reviewing.
Welcome to comment on this.
Thanks,
Edison
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Hi all,
I have a proposal to create a "develop"(or something like this) branch in TF-M for our feature development. The reasons for this are:
* Reduce the risk to broke the master branch directly especial when the CI cannot work rightly.
* We can use the "master" branch only for release, and in this, we do not need to freeze the patch merging when preparing the release.
More addition, we can create more branches for big features development, such as "develop/feature_a" or "develop/feature_b". All these new features branch need to be merged to the "develop" branch first and then release to the "master" branch.
This is different from the current patch upstream mode, and it needs to spend more time maintaining those branches. But I think it is more convenient for us to develop different features. We do not need to spend more time to fix the conflicts and to do rebase when other patches merge to master branch during patch reviewing.
Welcome to comment on this.
Thanks,
Edison
Thank Bill for updating this.
I want to use this thread to follow up on the topic 'secure interrupt' given in the 1st tech forum.
That is a prologue of the scheduler and interrupt designs. And I do see there are some use cases that I did not focus on, so I want to collect more user scenarios first, and then try to enhance the drafting design (will be published after I updated it base on your inputs).
About the secure interrupt usage:
- A secure interrupt would be introduced by a secure service call in general; is there any scenarios that there would be an interval secure interrupt since secure service want to do something? For example, a secure timer triggers to let secure service has the chance to do things in the background (not for an ongoing secure call from NSPE) after a period of time?
And the question about the system Alan mentioned, just want to confirm if it is a pure thread mode scheduling system? How does the system handle interrupts?
Thanks.
-----Original Message-----
From: TF-M <tf-m-bounces(a)lists.trustedfirmware.org> On Behalf Of Bill Fletcher via TF-M
Sent: Monday, December 9, 2019 7:57 PM
To: TF-M mailing list <tf-m(a)lists.trustedfirmware.org>
Subject: [TF-M] TF-M technical Forum slides and recording
Hi all,
I've posted links to the (updated) slide deck and a recording of the call on the meetings page of the Trusted Firmware website:
https://www.trustedfirmware.org/meetings/tf-m-technical-forum/
Regards
Bill
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[image: Linaro] <http://www.linaro.org/> *Bill Fletcher* | *Field Engineering*
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