KVM: x86/pmu: Introduce eventsel_hw to prepare for pmu event filtering

Browse source

Introduce eventsel_hw and fixed_ctr_ctrl_hw to store the actual HW value in
PMU event selector MSRs. In mediated PMU checks events before allowing the
event values written to the PMU MSRs. However, to match the HW behavior,
when PMU event checks fails, KVM should allow guest to read the value back.

This essentially requires an extra variable to separate the guest requested
value from actual PMU MSR value. Note this only applies to event selectors.

Signed-off-by: Mingwei Zhang <mizhang@google.com>
Co-developed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Tested-by: Xudong Hao <xudong.hao@intel.com>
Tested-by: Manali Shukla <manali.shukla@amd.com>
Link: https://patch.msgid.link/20251206001720.468579-25-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

...

This commit is contained in:

Mingwei Zhang 2025-12-05 16:17:00 -08:00 • committed by Sean Christopherson

parent 0ea0d63148

commit 02918f0077

4 changed files with 10 additions and 2 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

arch/x86/include/asm/kvm_host.h

View file

7

arch/x86/kvm/pmu.c

View file

1

arch/x86/kvm/svm/pmu.c

View file

2

arch/x86/kvm/vmx/pmu_intel.c

View file