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| author | Alexandru Elisei <alexandru.elisei@arm.com> | 2022-01-27 16:17:59 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2022-02-08 17:51:22 +0000 |
| commit | 583cda1b0e7d5d49db5fc15db623166310e36bf6 (patch) | |
| tree | 04b01167aa2bb323a3239bee42169206297dd6c5 /arch/arm64/kvm/pmu-emul.c | |
| parent | 6ee7fca2a4a023b14aa1f1f3c4f6c833116116ef (diff) | |
| download | linux-stable-583cda1b0e7d5d49db5fc15db623166310e36bf6.tar.gz linux-stable-583cda1b0e7d5d49db5fc15db623166310e36bf6.tar.bz2 linux-stable-583cda1b0e7d5d49db5fc15db623166310e36bf6.zip | |
KVM: arm64: Refuse to run VCPU if the PMU doesn't match the physical CPU
Userspace can assign a PMU to a VCPU with the KVM_ARM_VCPU_PMU_V3_SET_PMU
device ioctl. If the VCPU is scheduled on a physical CPU which has a
different PMU, the perf events needed to emulate a guest PMU won't be
scheduled in and the guest performance counters will stop counting. Treat
it as an userspace error and refuse to run the VCPU in this situation.
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220127161759.53553-7-alexandru.elisei@arm.com
Diffstat (limited to 'arch/arm64/kvm/pmu-emul.c')
| -rw-r--r-- | arch/arm64/kvm/pmu-emul.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 18361f367495..4526a5824dac 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -968,6 +968,7 @@ static int kvm_arm_pmu_v3_set_pmu(struct kvm_vcpu *vcpu, int pmu_id) } kvm->arch.arm_pmu = arm_pmu; + cpumask_copy(kvm->arch.supported_cpus, &arm_pmu->supported_cpus); ret = 0; break; } |