arm64/sme: Don't flush SVE register state when handling SME traps

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commit 714f3cbd70 upstream.

Currently as part of handling a SME access trap we flush the SVE register
state. This is not needed and would corrupt register state if the task has
access to the SVE registers already. For non-streaming mode accesses the
required flushing will be done in the SVE access trap. For streaming
mode SVE register accesses the architecture guarantees that the register
state will be flushed when streaming mode is entered or exited so there is
no need for us to do so. Simply remove the register initialisation.

Fixes: 8bd7f91c03 ("arm64/sme: Implement traps and syscall handling for SME")
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20220817182324.638214-5-broonie@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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Mark Brown 2022-08-17 19:23:24 +01:00 • committed by Greg Kroah-Hartman

parent a8d79f9d1a

commit 0761b0e818

1 changed files with 0 additions and 11 deletions

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arch/arm64/kernel/fpsimd.c

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