Currently when deciding if we need to save FFR when in streaming mode prior to EFI calls we check if FA64 is supported by the system. Since KVM guest support will mean that FA64 might be enabled and disabled at runtime switch to checking if traps for FA64 are enabled in SMCR_EL1 instead.
Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/kernel/fpsimd.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 77f9dfaffe8b..de2897d6208c 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -1908,6 +1908,11 @@ static bool efi_sm_state; * either doing something wrong or you need to propose some refactoring. */
+static bool fa64_enabled(void) +{ + return read_sysreg_s(SYS_SMCR_EL1) & SMCR_ELx_FA64; +} + /* * __efi_fpsimd_begin(): prepare FPSIMD for making an EFI runtime services call */ @@ -1940,7 +1945,7 @@ void __efi_fpsimd_begin(void) * Unless we have FA64 FFR does not * exist in streaming mode. */ - if (!system_supports_fa64()) + if (!fa64_enabled()) ffr = !(svcr & SVCR_SM_MASK); }
@@ -1988,7 +1993,7 @@ void __efi_fpsimd_end(void) * Unless we have FA64 FFR does not * exist in streaming mode. */ - if (!system_supports_fa64()) + if (!fa64_enabled()) ffr = false; } }