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arm64/sme: Fix EFI save/restore 

The EFI save/restore code is confused. When saving the check for saving
FFR is inverted due to confusion with the streaming mode check, and when
restoring we check if we need to restore FFR by checking the percpu
efi_sm_state without the required wrapper rather than based on the
combination of FA64 support and streaming mode.

Fixes: e0838f6373 ("arm64/sme: Save and restore streaming mode over EFI runtime calls")
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220602124132.3528951-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Mark Brown 2022-06-02 14:41:32 +02:00 committed by Catalin Marinas
parent bb314511b6
commit 2e990e6322
1 changed files with 14 additions and 4 deletions
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18
arch/arm64/kernel/fpsimd.c
View File

@ -1916,10 +1916,15 @@ void __efi_fpsimd_begin(void)
if (system_supports_sme()) {
svcr = read_sysreg_s(SYS_SVCR);
if (!system_supports_fa64())
ffr = svcr & SVCR_SM_MASK;
__this_cpu_write(efi_sm_state,
svcr & SVCR_SM_MASK);
__this_cpu_write(efi_sm_state, ffr);
/*
* Unless we have FA64 FFR does not
* exist in streaming mode.
*/
if (!system_supports_fa64())
ffr = !(svcr & SVCR_SM_MASK);
}
sve_save_state(sve_state + sve_ffr_offset(sve_max_vl()),
@ -1964,8 +1969,13 @@ void __efi_fpsimd_end(void)
sysreg_clear_set_s(SYS_SVCR,
0,
SVCR_SM_MASK);
/*
* Unless we have FA64 FFR does not
* exist in streaming mode.
*/
if (!system_supports_fa64())
ffr = efi_sm_state;
ffr = false;
}
}