From: Suzuki K Poulose suzuki.poulose@arm.com
commit 449443c03d8cfdacf7313e17779a2594ebf87e6d upstream.
The NO_FPSIMD capability is defined with scope SYSTEM, which implies that the "absence" of FP/SIMD on at least one CPU is detected only after all the SMP CPUs are brought up. However, we use the status of this capability for every context switch. So, let us change the scope to LOCAL_CPU to allow the detection of this capability as and when the first CPU without FP is brought up.
Also, the current type allows hotplugged CPU to be brought up without FP/SIMD when all the current CPUs have FP/SIMD and we have the userspace up. Fix both of these issues by changing the capability to BOOT_RESTRICTED_LOCAL_CPU_FEATURE.
Fixes: 82e0191a1aa11abf ("arm64: Support systems without FP/ASIMD") Cc: Will Deacon will@kernel.org Cc: Mark Rutland mark.rutland@arm.com Reviewed-by: Ard Biesheuvel ardb@kernel.org Reviewed-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Will Deacon will@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/arm64/kernel/cpufeature.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1368,7 +1368,7 @@ static const struct arm64_cpu_capabiliti { /* FP/SIMD is not implemented */ .capability = ARM64_HAS_NO_FPSIMD, - .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .type = ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE, .min_field_value = 0, .matches = has_no_fpsimd, },