diff options
| author | Mark Brown <broonie@kernel.org> | 2023-08-03 00:46:39 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-11 12:08:21 +0200 |
| commit | 654c1dd350c746244e4dd4fe1fde577a2dc93d96 (patch) | |
| tree | ffdf78882cf907103a31618dda8b1eb99ce7e516 /arch | |
| parent | bae353469a282d4a0ac27f07a0ba5137ad1a049d (diff) | |
| download | linux-654c1dd350c746244e4dd4fe1fde577a2dc93d96.tar.gz | |
arm64/fpsimd: Clear SME state in the target task when setting the VL
commit c9bb40b7f786662e33d71afe236442b0b61f0446 upstream.
When setting SME vector lengths we clear TIF_SME to reenable SME traps,
doing a reallocation of the backing storage on next use. We do this using
clear_thread_flag() which operates on the current thread, meaning that when
setting the vector length via ptrace we may both not force traps for the
target task and force a spurious flush of any SME state that the tracing
task may have.
Clear the flag in the target task.
Fixes: e12310a0d30f ("arm64/sme: Implement ptrace support for streaming mode SVE registers")
Reported-by: David Spickett <David.Spickett@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230803-arm64-fix-ptrace-tif-sme-v1-1-88312fd6fbfd@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/kernel/fpsimd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 8fa9b1fa211a..f7dbc0074cb0 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -864,7 +864,7 @@ int vec_set_vector_length(struct task_struct *task, enum vec_type type, */ task->thread.svcr &= ~(SVCR_SM_MASK | SVCR_ZA_MASK); - clear_thread_flag(TIF_SME); + clear_tsk_thread_flag(task, TIF_SME); free_sme = true; } } |