diff options
| author | Wei Wang <wei.w.wang@intel.com> | 2021-12-17 07:49:34 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-20 09:19:18 +0100 |
| commit | 7b98f61b838821d9c66086ede96d02e5468565bb (patch) | |
| tree | dfb23d4989fde59509375e799e7a4946162d98af /arch/x86 | |
| parent | 5c69ba9e80f0acae045454c4d98e6cc01df8d774 (diff) | |
KVM: x86: remove PMU FIXED_CTR3 from msrs_to_save_all
commit 9fb12fe5b93b94b9e607509ba461e17f4cc6a264 upstream.
The fixed counter 3 is used for the Topdown metrics, which hasn't been
enabled for KVM guests. Userspace accessing to it will fail as it's not
included in get_fixed_pmc(). This breaks KVM selftests on ICX+ machines,
which have this counter.
To reproduce it on ICX+ machines, ./state_test reports:
==== Test Assertion Failure ====
lib/x86_64/processor.c:1078: r == nmsrs
pid=4564 tid=4564 - Argument list too long
1 0x000000000040b1b9: vcpu_save_state at processor.c:1077
2 0x0000000000402478: main at state_test.c:209 (discriminator 6)
3 0x00007fbe21ed5f92: ?? ??:0
4 0x000000000040264d: _start at ??:?
Unexpected result from KVM_GET_MSRS, r: 17 (failed MSR was 0x30c)
With this patch, it works well.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Message-Id: <20211217124934.32893-1-wei.w.wang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: e2ada66ec418 ("kvm: x86: Add Intel PMU MSRs to msrs_to_save[]")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/x86.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0aaf40be956f..1f7dfa5aa42d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1218,7 +1218,7 @@ static const u32 msrs_to_save_all[] = { MSR_IA32_UMWAIT_CONTROL, MSR_ARCH_PERFMON_FIXED_CTR0, MSR_ARCH_PERFMON_FIXED_CTR1, - MSR_ARCH_PERFMON_FIXED_CTR0 + 2, MSR_ARCH_PERFMON_FIXED_CTR0 + 3, + MSR_ARCH_PERFMON_FIXED_CTR0 + 2, MSR_CORE_PERF_FIXED_CTR_CTRL, MSR_CORE_PERF_GLOBAL_STATUS, MSR_CORE_PERF_GLOBAL_CTRL, MSR_CORE_PERF_GLOBAL_OVF_CTRL, MSR_ARCH_PERFMON_PERFCTR0, MSR_ARCH_PERFMON_PERFCTR1, |