]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
arm64: cpufeature: Fix the type of no FP/SIMD capability
authorSuzuki K Poulose <suzuki.poulose@arm.com>
Mon, 13 Jan 2020 23:30:19 +0000 (23:30 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 14 Feb 2020 21:34:17 +0000 (16:34 -0500)
commit1a2b07a2c3dde4e2ce6398a7a7187b49489493ad
treee9982eab52cc896d5cc96d9824024bcbb284f068
parentba95651cefe1d1c4a262f8e78548812cd6ab073c
arm64: cpufeature: Fix the type of no FP/SIMD capability

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