diff options
author | Like Xu <[email protected]> | 2021-11-18 21:03:20 +0800 |
---|---|---|
committer | Paolo Bonzini <[email protected]> | 2021-12-02 04:11:50 -0500 |
commit | cb1d220da0faa5ca0deb93449aff953f0c2cce6d (patch) | |
tree | 98a3d02918490581660702135f186a368a4212c5 | |
parent | 7cfc5c653b07782e7059527df8dc1e3143a7591e (diff) |
KVM: x86/pmu: Fix reserved bits for AMD PerfEvtSeln register
If we run the following perf command in an AMD Milan guest:
perf stat \
-e cpu/event=0x1d0/ \
-e cpu/event=0x1c7/ \
-e cpu/umask=0x1f,event=0x18e/ \
-e cpu/umask=0x7,event=0x18e/ \
-e cpu/umask=0x18,event=0x18e/ \
./workload
dmesg will report a #GP warning from an unchecked MSR access
error on MSR_F15H_PERF_CTLx.
This is because according to APM (Revision: 4.03) Figure 13-7,
the bits [35:32] of AMD PerfEvtSeln register is a part of the
event select encoding, which extends the EVENT_SELECT field
from 8 bits to 12 bits.
Opportunistically update pmu->reserved_bits for reserved bit 19.
Reported-by: Jim Mattson <[email protected]>
Fixes: ca724305a2b0 ("KVM: x86/vPMU: Implement AMD vPMU code for KVM")
Signed-off-by: Like Xu <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
-rw-r--r-- | arch/x86/kvm/svm/pmu.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c index 871c426ec389..b4095dfeeee6 100644 --- a/arch/x86/kvm/svm/pmu.c +++ b/arch/x86/kvm/svm/pmu.c @@ -281,7 +281,7 @@ static void amd_pmu_refresh(struct kvm_vcpu *vcpu) pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS; pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1; - pmu->reserved_bits = 0xffffffff00200000ull; + pmu->reserved_bits = 0xfffffff000280000ull; pmu->version = 1; /* not applicable to AMD; but clean them to prevent any fall out */ pmu->counter_bitmask[KVM_PMC_FIXED] = 0; |