916e3a4f95
If the PMU is broken due to firmware issues, check_hw_exists() will return false but perf_get_x86_pmu_capability() will still return data from x86_pmu. Likewise if some of the hotplug callbacks cannot be installed the contents of x86_pmu will not be reverted. Handle the failure in both cases by clearing x86_pmu if init_hw_perf_events() or reverts to software events only. Co-developed-by: Like Xu <likexu@tencent.com> Signed-off-by: Like Xu <likexu@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>