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| author | Zenghui Yu <yuzenghui@huawei.com> | 2019-07-18 10:15:10 +0200 |
|---|---|---|
| committer | Marc Zyngier <marc.zyngier@arm.com> | 2019-07-23 10:23:44 +0200 |
| commit | bca031e2c8aa22a978a2452bf959e27e9fa73dc7 (patch) | |
| tree | c7e80e707e3abc3d924254432f4159b36b51631f /include | |
| parent | Linus 5.3-rc1 (diff) | |
| download | linux-bca031e2c8aa22a978a2452bf959e27e9fa73dc7.tar.xz linux-bca031e2c8aa22a978a2452bf959e27e9fa73dc7.zip | |
KVM: arm/arm64: Introduce kvm_pmu_vcpu_init() to setup PMU counter index
We use "pmc->idx" and the "chained" bitmap to determine if the pmc is
chained, in kvm_pmu_pmc_is_chained(). But idx might be uninitialized
(and random) when we doing this decision, through a KVM_ARM_VCPU_INIT
ioctl -> kvm_pmu_vcpu_reset(). And the test_bit() against this random
idx will potentially hit a KASAN BUG [1].
In general, idx is the static property of a PMU counter that is not
expected to be modified across resets, as suggested by Julien. It
looks more reasonable if we can setup the PMU counter idx for a vcpu
in its creation time. Introduce a new function - kvm_pmu_vcpu_init()
for this basic setup. Oh, and the KASAN BUG will get fixed this way.
[1] https://www.spinics.net/lists/kvm-arm/msg36700.html
Fixes: 80f393a23be6 ("KVM: arm/arm64: Support chained PMU counters")
Suggested-by: Andrew Murray <andrew.murray@arm.com>
Suggested-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/kvm/arm_pmu.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 16c769a7f979..6db030439e29 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -34,6 +34,7 @@ struct kvm_pmu { u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx); void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val); u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu); +void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu); void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu); void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu); void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val); @@ -71,6 +72,7 @@ static inline u64 kvm_pmu_valid_counter_mask(struct kvm_vcpu *vcpu) { return 0; } +static inline void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu) {} static inline void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu) {} static inline void kvm_pmu_vcpu_destroy(struct kvm_vcpu *vcpu) {} static inline void kvm_pmu_disable_counter_mask(struct kvm_vcpu *vcpu, u64 val) {} |