Hi,
Commit 327f4bb0cf20 ("fix(el3_runtime): allow SErrors when executing in EL3")[1], seems disruptive for LTS branch at this stage. Therefore we, the LTS maintainers, propose to revert it in the lts-v2.8 branch. The reason is that if a misbehaving binary is running in a lower EL, e.g. one which has external aborts masked while executing instructions which cause SErrors, then it's possible for those SErrors to be received by EL3 even if they weren't caused by it. This is a change in the contract between EL3 and lower ELs, that existed at the time when TF-A v2.8 was released. LTS 2.8 is based on TF-A 2.8.
Revert patch, which is not yet submitted, can be found here[2]. If you have any comments or objections please share before the end of Friday 24th February Pacific Time. We'll merge it after that.
Thanks, Okash
[1] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/18953 [2] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/19094
Hi,
This patch has now been merged to the lts-v2.8 branch.
-Varun
-----Original Message----- From: Okash Khawaja okash@google.com Sent: Wednesday, February 22, 2023 12:34 PM To: tfa-lts@lists.trustedfirmware.org Subject: [TFA-LTS] [Feedback Requested] Reverting setting SCR_EL3.EA in EL3
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Hi,
Commit 327f4bb0cf20 ("fix(el3_runtime): allow SErrors when executing in EL3")[1], seems disruptive for LTS branch at this stage. Therefore we, the LTS maintainers, propose to revert it in the lts-v2.8 branch. The reason is that if a misbehaving binary is running in a lower EL, e.g. one which has external aborts masked while executing instructions which cause SErrors, then it's possible for those SErrors to be received by EL3 even if they weren't caused by it. This is a change in the contract between EL3 and lower ELs, that existed at the time when TF-A v2.8 was released. LTS 2.8 is based on TF-A 2.8.
Revert patch, which is not yet submitted, can be found here[2]. If you have any comments or objections please share before the end of Friday 24th February Pacific Time. We'll merge it after that.
Thanks, Okash
[1] https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Freview.tru... [2] https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Freview.tru... _______________________________________________ TF-A LTS mailing list -- tfa-lts@lists.trustedfirmware.org To unsubscribe send an email to tfa-lts-leave@lists.trustedfirmware.org
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-
Okash Khawaja -
Varun Wadekar