From: Mark Brown <broonie@kernel.org> mainline inclusion from mainline-v5.19-rc2 commit 2e990e63220bb01e2755b55b93878ce7c8cbe747 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I5ITJT CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... ------------------------------------------------- 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: e0838f6373e5 ("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> Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com> --- arch/arm64/kernel/fpsimd.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 649b6653a570..18b760388540 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1877,10 +1877,15 @@ 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()), @@ -1925,8 +1930,13 @@ 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; } } -- 2.20.1