• Kyle Huey's avatar
    KVM: x86/svm: Account for family 17h event renumberings in amd_pmc_perf_hw_id · 5eb84932
    Kyle Huey authored
    Zen renumbered some of the performance counters that correspond to the
    well known events in perf_hw_id. This code in KVM was never updated for
    that, so guest that attempt to use counters on Zen that correspond to the
    pre-Zen perf_hw_id values will silently receive the wrong values.
    
    This has been observed in the wild with rr[0] when running in Zen 3
    guests. rr uses the retired conditional branch counter 00d1 which is
    incorrectly recognized by KVM as PERF_COUNT_HW_STALLED_CYCLES_BACKEND.
    
    [0] https://rr-project.org/Signed-off-by: default avatarKyle Huey <me@kylehuey.com>
    Message-Id: <20220503050136.86298-1-khuey@kylehuey.com>
    Cc: stable@vger.kernel.org
    [Check guest family, not host. - Paolo]
    Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
    5eb84932
pmu.c 8.92 KB