kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU
stable inclusion from stable-v5.10.115 commit 599fc32e7421d7a591ee78bb4f3b79c54d51065c category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5IZ9C Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=599fc32e7421d7a591ee78bb4f3b79c54d51065c -------------------------------- [ Upstream commit 5a1bde46 ] On some x86 processors, CPUID leaf 0xA provides information on Architectural Performance Monitoring features. It advertises a PMU version which Qemu uses to determine the availability of additional MSRs to manage the PMCs. Upon receiving a KVM_GET_SUPPORTED_CPUID ioctl request for the same, the kernel constructs return values based on the x86_pmu_capability irrespective of the vendor. This leaf and the additional MSRs are not supported on AMD and Hygon processors. If AMD PerfMonV2 is detected, the PMU version is set to 2 and guest startup breaks because of an attempt to access a non-existent MSR. Return zeros to avoid this. Fixes: a6c06ed1 ("KVM: Expose the architectural performance monitoring CPUID leaf") Reported-by: NVasant Hegde <vasant.hegde@amd.com> Signed-off-by: NSandipan Das <sandipan.das@amd.com> Message-Id: <3fef83d9c2b2f7516e8ff50d60851f29a4bcb716.1651058600.git.sandipan.das@amd.com> Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com> Signed-off-by: NSasha Levin <sashal@kernel.org> Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com> Acked-by: NXie XiuQi <xiexiuqi@huawei.com>
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