From 06e0b802583d7bbc075476d90da995ee3e6053d5 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Tue, 19 Apr 2022 19:27:52 +0100 Subject: [PATCH] KVM: arm64: Expose the WFXT feature to guests Plumb in the capability, and expose WFxT to guests when available. Signed-off-by: Marc Zyngier Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/20220419182755.601427-8-maz@kernel.org --- arch/arm64/kernel/cpufeature.c | 11 +++++++++++ arch/arm64/kvm/sys_regs.c | 2 ++ 2 files changed, 13 insertions(+) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index a6db8ca04429..945190ebadd5 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -2443,6 +2443,17 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .matches = has_cpuid_feature, .min_field_value = 1, }, + { + .desc = "WFx with timeout", + .capability = ARM64_HAS_WFXT, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .sys_reg = SYS_ID_AA64ISAR2_EL1, + .sign = FTR_UNSIGNED, + .field_pos = ID_AA64ISAR2_WFXT_SHIFT, + .field_width = 4, + .matches = has_cpuid_feature, + .min_field_value = ID_AA64ISAR2_WFXT_SUPPORTED, + }, {}, }; diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 7b45c040cc27..cc9a77546cc0 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1144,6 +1144,8 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, if (!vcpu_has_ptrauth(vcpu)) val &= ~(ARM64_FEATURE_MASK(ID_AA64ISAR2_APA3) | ARM64_FEATURE_MASK(ID_AA64ISAR2_GPA3)); + if (!cpus_have_final_cap(ARM64_HAS_WFXT)) + val &= ~ARM64_FEATURE_MASK(ID_AA64ISAR2_WFXT); break; case SYS_ID_AA64DFR0_EL1: /* Limit debug to ARMv8.0 */