From: Yeoreum Yun Date: Wed, 18 Jun 2025 09:29:50 +0000 (+0100) Subject: arm64/cpufeature: Add MTE_STORE_ONLY feature X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=33e943a228535fe5eb64b746d2b7b6b187aaa77a;p=thirdparty%2Fkernel%2Fstable.git arm64/cpufeature: Add MTE_STORE_ONLY feature Since ARMv8.9, FEAT_MTE_STORE_ONLY can be used to restrict raise of tag check fault on store operation only. add MTE_STORE_ONLY feature. Signed-off-by: Yeoreum Yun Reviewed-by: Mark Brown Link: https://lore.kernel.org/r/20250618092957.2069907-2-yeoreum.yun@arm.com Signed-off-by: Catalin Marinas --- diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 8a5284c733b7..fdc48aa1f0e2 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -321,6 +321,7 @@ static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = { static const struct arm64_ftr_bits ftr_id_aa64pfr2[] = { ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR2_EL1_FPMR_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR2_EL1_MTEFAR_SHIFT, 4, ID_AA64PFR2_EL1_MTEFAR_NI), + ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR2_EL1_MTESTOREONLY_SHIFT, 4, ID_AA64PFR2_EL1_MTESTOREONLY_NI), ARM64_FTR_END, }; @@ -2882,6 +2883,13 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .matches = has_cpuid_feature, ARM64_CPUID_FIELDS(ID_AA64PFR2_EL1, MTEFAR, IMP) }, + { + .desc = "Store Only MTE Tag Check", + .capability = ARM64_MTE_STORE_ONLY, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .matches = has_cpuid_feature, + ARM64_CPUID_FIELDS(ID_AA64PFR2_EL1, MTESTOREONLY, IMP) + }, #endif /* CONFIG_ARM64_MTE */ { .desc = "RCpc load-acquire (LDAPR)", diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps index fe8f4f8ce95c..b96cb6d6bcaa 100644 --- a/arch/arm64/tools/cpucaps +++ b/arch/arm64/tools/cpucaps @@ -69,6 +69,7 @@ MPAM_HCR MTE MTE_ASYMM MTE_FAR +MTE_STORE_ONLY SME SME_FA64 SME2