linux-toradex.git/tools/testing/selftests/rseq/run_legacy_check.sh, branch master Linux kernel for Apalis and Colibri modules selftests/rseq: Validate legacy behavior 2026-05-06T15:39:01+00:00 Thomas Gleixner tglx@kernel.org 2026-04-26T15:51:07+00:00 fdf4eb632683bfc2840acebe62716cb468d43e10 The RSEQ legacy mode behavior requires that the ID fields in the rseq region are unconditionally updated on every context switch and before signal delivery even if not required by the ABI specification. To ensure that this behavior is preserved for legacy users in the future, add a test which validates that with a sleep() and a signal sent to self. Provide a run script which prevents GLIBC from registering a RSEQ region, so that the test can register it's own legacy sized region. Fixes: 566d8015f7ee ("rseq: Avoid CPU/MM CID updates when no event pending") Signed-off-by: Thomas Gleixner <tglx@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dmitry Vyukov <dvyukov@google.com> Tested-by: Dmitry Vyukov <dvyukov@google.com> Link: https://patch.msgid.link/20260428224427.764705536%40kernel.org Cc: stable@vger.kernel.org 
The RSEQ legacy mode behavior requires that the ID fields in the rseq
region are unconditionally updated on every context switch and before
signal delivery even if not required by the ABI specification.

To ensure that this behavior is preserved for legacy users in the future,
add a test which validates that with a sleep() and a signal sent to self.

Provide a run script which prevents GLIBC from registering a RSEQ region,
so that the test can register it's own legacy sized region.

Fixes: 566d8015f7ee ("rseq: Avoid CPU/MM CID updates when no event pending")
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Link: https://patch.msgid.link/20260428224427.764705536%40kernel.org
Cc: stable@vger.kernel.org