From 4e8c8b80f8b0b0e24c59a65369167ab2f67819f2 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 2 Jun 2022 14:41:32 +0200 Subject: [PATCH] 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: ecf8b6d19999 ("arm64/sme: Save and restore streaming mode over EFI runtime calls") Reported-by: kernel test robot Reviewed-by: Catalin Marinas Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20220602124132.3528951-1-broonie@kernel.org Signed-off-by: Catalin Marinas --- 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 f1d476fa50a9e..aecf3071efddd 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -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; } } -- 2.39.5