diff options
| author | Sandipan Das <sandipan.das@amd.com> | 2022-04-27 17:01:49 +0530 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-05-12 12:20:25 +0200 |
| commit | dac10d64c77a589a6bcfe75d180e8a5cab5e70f1 (patch) | |
| tree | f4d7cfcd13b81a531e6f909188de95804e6f6b14 /net/ipv6/tcp_ipv6.c | |
| parent | 2fc50abb0b3cbeb0cdae129b4ea0437ea35215df (diff) | |
kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU
[ Upstream commit 5a1bde46f98b893cda6122b00e94c0c40a6ead3c ]
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: a6c06ed1a60a ("KVM: Expose the architectural performance monitoring CPUID leaf")
Reported-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Message-Id: <3fef83d9c2b2f7516e8ff50d60851f29a4bcb716.1651058600.git.sandipan.das@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net/ipv6/tcp_ipv6.c')
0 files changed, 0 insertions, 0 deletions