On 26-03-17, Jens Wiklander wrote:
Hi,
On Tue, Mar 17, 2026 at 9:51 AM Krzysztof Kozlowski krzk@kernel.org wrote:
On Mon, Mar 16, 2026 at 08:41:50AM +0100, Jens Wiklander wrote:
Hello arm-soc maintainers,
Please pull this patch removing the refcounting of kernel pages within the TEE shared memory helper.
Thanks, Jens
The following changes since commit 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f:
Linux 7.0-rc1 (2026-02-22 13:18:59 -0800)
are available in the Git repository at:
git://git.kernel.org/pub/scm/linux/kernel/git/jenswi/linux-tee.git tags/tee-fix-for-v7.0
for you to fetch changes up to 08d9a4580f71120be3c5b221af32dca00a48ceb0:
tee: shm: Remove refcounting of kernel pages (2026-03-03 09:03:04 +0100)
TEE shared memory update for 7.0
Remove refcounting of kernel pages in register_shm_helper() to support slab allocations.
That's a supposed fix for a year old commit, not current RC, and the commit msg does not explain what is the bug being fixed here. Looks like it is doing improvement, not a fix. Can you provide here more explanation of the actual bug being fixed to justify this going to current RC fixes?
I'm under the impression that it is a fix rather than an improvement. However, since it has been stewing for a while, it's clearly not urgent. I don't have anything specific on the bug fix, other than that we're supposed to stop taking those refcounts. Perhaps Sumit, Marco, or Matthew can add something?
It's a long outstanding fix regarding memory page management. The userspace gets informed about this memory API misuse via a warning print incl. a backtrace. This gets triggered only if userspace uses OP-TEE trusted-keys or the OP-TEE EFI variables. Therefore I would like to get it into 7.0 but 7.1 fine too.
Regards, Marco
Cheers, Jens