KVM: x86/pmu: Prevent the PMU from counting disallowed events

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When counting "Instructions Retired" (0xc0) in a guest, KVM will
occasionally increment the PMU counter regardless of if that event is
being filtered. This is because some PMU events are incremented via
kvm_pmu_trigger_event(), which doesn't know about the event filter. Add
the event filter to kvm_pmu_trigger_event(), so events that are
disallowed do not increment their counters.

Fixes: 9cd803d496 ("KVM: x86: Update vPMCs when retiring instructions")
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20230307141400.1486314-2-aaronlewis@google.com
[sean: prepend "pmc" to the new function]
Signed-off-by: Sean Christopherson <seanjc@google.com>

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Aaron Lewis 2023-03-07 14:13:56 +00:00 • committed by Sean Christopherson

parent 4fa5843d81

commit dfdeda67ea

1 changed files with 8 additions and 5 deletions

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arch/x86/kvm/pmu.c

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