Mark, On 03/05/18 14:20, Mark Rutland wrote:
So that we can dynamically handle the presence of pointer authentication functionality, wire up probing code in cpufeature.c. From ARMv8.3 onwards, ID_AA64ISAR1 is no longer entirely RES0, and now has four fields describing the presence of pointer authentication functionality: * APA - address authentication present, using an architected algorithm * API - address authentication present, using an IMP DEF algorithm * GPA - generic authentication present, using an architected algorithm * GPI - generic authentication present, using an IMP DEF algorithm For the moment we only care about address authentication, so we only need to check APA and API. It is assumed that if all CPUs support an IMP DEF algorithm, the same algorithm is used across all CPUs. Note that when we implement KVM support, we will also need to ensure that CPUs have uniform support for GPA and GPI. Signed-off-by: Mark Rutland <mark.rutland@xxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> --- arch/arm64/include/asm/cpucaps.h | 5 ++++- arch/arm64/kernel/cpufeature.c | 47 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index bc51b72fafd4..9dcb4d1b14f5 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -48,7 +48,10 @@ #define ARM64_HAS_CACHE_IDC 27 #define ARM64_HAS_CACHE_DIC 28 #define ARM64_HW_DBM 29 +#define ARM64_HAS_ADDRESS_AUTH_ARCH 30 +#define ARM64_HAS_ADDRESS_AUTH_IMP_DEF 31
Where are these caps used ? I couldn't find anything in the series that uses them. Otherwise looks good to me. Cheers Suzuki _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
