diff options
| author | Mark Rutland <mark.rutland@arm.com> | 2025-04-09 17:40:05 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-06-19 15:31:35 +0200 |
| commit | 2756dac036113c7826f5b79b7f61ccd4c51093b3 (patch) | |
| tree | 1f83405b774d267a6a65efc5fdfcbc911f361d89 | |
| parent | 55d52af498daea75aa03ba9b7e444c8ae495ac20 (diff) | |
arm64/fpsimd: Reset FPMR upon exec()
[ Upstream commit a90878f297d3dba906a6261deccb1bd4a791ba52 ]
An exec() is expected to reset all FPSIMD/SVE/SME state, and barring
special handling of the vector lengths, the state is expected to reset
to zero. This reset is handled in fpsimd_flush_thread(), which the core
exec() code calls via flush_thread().
When support was added for FPMR, no logic was added to
fpsimd_flush_thread() to reset the FPMR value, and thus it is
erroneously inherited across an exec().
Add the missing reset of FPMR.
Fixes: 203f2b95a882 ("arm64/fpsimd: Support FEAT_FPMR")
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Mark Brown <broonie@kernel.org>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20250409164010.3480271-9-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | arch/arm64/kernel/fpsimd.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 9f2b83c50f7d..8b8cd9d23823 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1663,6 +1663,9 @@ void fpsimd_flush_thread(void) current->thread.svcr = 0; } + if (system_supports_fpmr()) + current->thread.uw.fpmr = 0; + current->thread.fp_type = FP_STATE_FPSIMD; put_cpu_fpsimd_context(); |