diff options
| author | Wei Huang <wei@redhat.com> | 2016-11-16 09:20:57 +0000 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2016-11-18 09:02:04 +0000 |
| commit | 9e3f7a29694049edd728e2400ab57ad7553e5aa9 (patch) | |
| tree | 1afa6545f2e297504d5b260ab1f107f2da2fcea0 /arch/arm64/kvm/sys_regs.c | |
| parent | d42c79701a3ee5c38fbbc82f98a140420bd40134 (diff) | |
| download | lwn-9e3f7a29694049edd728e2400ab57ad7553e5aa9.tar.gz lwn-9e3f7a29694049edd728e2400ab57ad7553e5aa9.zip | |
arm64: KVM: pmu: Fix AArch32 cycle counter access
We're missing the handling code for the cycle counter accessed
from a 32bit guest, leading to unexpected results.
Cc: stable@vger.kernel.org # 4.6+
Signed-off-by: Wei Huang <wei@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'arch/arm64/kvm/sys_regs.c')
| -rw-r--r-- | arch/arm64/kvm/sys_regs.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index f302fdb3a030..87e7e6608cd8 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -597,8 +597,14 @@ static bool access_pmu_evcntr(struct kvm_vcpu *vcpu, idx = ARMV8_PMU_CYCLE_IDX; } else { - BUG(); + return false; } + } else if (r->CRn == 0 && r->CRm == 9) { + /* PMCCNTR */ + if (pmu_access_event_counter_el0_disabled(vcpu)) + return false; + + idx = ARMV8_PMU_CYCLE_IDX; } else if (r->CRn == 14 && (r->CRm & 12) == 8) { /* PMEVCNTRn_EL0 */ if (pmu_access_event_counter_el0_disabled(vcpu)) @@ -606,7 +612,7 @@ static bool access_pmu_evcntr(struct kvm_vcpu *vcpu, idx = ((r->CRm & 3) << 3) | (r->Op2 & 7); } else { - BUG(); + return false; } if (!pmu_counter_idx_valid(vcpu, idx)) |