Revert "KVM: x86: always allow host-initiated writes to PMU MSRs"

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Revert the hack to allow host-initiated accesses to all "PMU" MSRs,
as intel_is_valid_msr() returns true for _all_ MSRs, regardless of whether
or not it has a snowball's chance in hell of actually being a PMU MSR.

That mostly gets papered over by the actual get/set helpers only handling
MSRs that they knows about, except there's the minor detail that
kvm_pmu_{g,s}et_msr() eat reads and writes when the PMU is disabled.
I.e. KVM will happy allow reads and writes to _any_ MSR if the PMU is
disabled, either via module param or capability.

This reverts commit d1c88a4020.

Fixes: d1c88a4020 ("KVM: x86: always allow host-initiated writes to PMU MSRs")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220611005755.753273-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

...

This commit is contained in:

Sean Christopherson 2022-06-11 00:57:52 +00:00 • committed by Paolo Bonzini

parent 5d4283df5a

commit 545feb96c0

5 changed files with 20 additions and 27 deletions

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4

arch/x86/kvm/pmu.c

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4

arch/x86/kvm/pmu.h

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2

arch/x86/kvm/svm/pmu.c

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27

arch/x86/kvm/vmx/pmu_intel.c

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10

arch/x86/kvm/x86.c

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