diff options
| author | Marc Zyngier <maz@kernel.org> | 2021-03-05 19:52:51 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-03-06 10:18:40 +0100 |
| commit | f27647b588c13647a60074b5a8dd39a86d919a1d (patch) | |
| tree | 99a47bf8bf42dc6994eb98191dc0dd4dbbff080b /arch/arm64/kvm | |
| parent | KVM: arm64: Turn kvm_arm_support_pmu_v3() into a static key (diff) | |
| download | linux-f27647b588c13647a60074b5a8dd39a86d919a1d.tar.xz linux-f27647b588c13647a60074b5a8dd39a86d919a1d.zip | |
KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is available
When running under a nesting hypervisor, it isn't guaranteed that
the virtual HW will include a PMU. In which case, let's not try
to access the PMU registers in the world switch, as that'd be
deadly.
Reported-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>
Link: https://lore.kernel.org/r/20210209114844.3278746-3-maz@kernel.org
Message-Id: <20210305185254.3730990-6-maz@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/arm64/kvm')
| -rw-r--r-- | arch/arm64/kvm/hyp/include/hyp/switch.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 54f4860cd87c..6c1f51f25eb3 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -90,15 +90,18 @@ static inline void __activate_traps_common(struct kvm_vcpu *vcpu) * counter, which could make a PMXEVCNTR_EL0 access UNDEF at * EL1 instead of being trapped to EL2. */ - write_sysreg(0, pmselr_el0); - write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); + if (kvm_arm_support_pmu_v3()) { + write_sysreg(0, pmselr_el0); + write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); + } write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2); } static inline void __deactivate_traps_common(void) { write_sysreg(0, hstr_el2); - write_sysreg(0, pmuserenr_el0); + if (kvm_arm_support_pmu_v3()) + write_sysreg(0, pmuserenr_el0); } static inline void ___activate_traps(struct kvm_vcpu *vcpu) |