On Fri, Apr 29, 2022 at 08:28:48PM -0000, tip-bot2 for Sandipan Das wrote: > The following commit has been merged into the perf/core branch of tip: > > Commit-ID: fafd15ab6dc1fdfff66908e6d9231b124e1875cf > Gitweb: https://git.kernel.org/tip/fafd15ab6dc1fdfff66908e6d9231b124e1875cf > Author: Sandipan Das <sandipan.das@xxxxxxx> > AuthorDate: Thu, 21 Apr 2022 11:16:59 +05:30 > Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> > CommitterDate: Fri, 29 Apr 2022 11:06:27 +02:00 > > kvm: x86/cpuid: Fix CPUID leaf 0xA > > 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 > processors. If 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@xxxxxxx> > Signed-off-by: Sandipan Das <sandipan.das@xxxxxxx> > Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> > Link: https://lkml.kernel.org/r/54bc7fe4cadf6bdef823bab1fba43d4891d2e1a9.1650515382.git.sandipan.das@xxxxxxx > --- > arch/x86/kvm/cpuid.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index b24ca7f..ae1d963 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -887,6 +887,12 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) > union cpuid10_eax eax; > union cpuid10_edx edx; > > + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD || > + boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) { > + entry->eax = entry->ebx = entry->ecx = entry->edx = 0; > + break; > + } > + This is all fine and dandy but this patch in tip conflicts with the very similar patch of yours: 5a1bde46f98b ("kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU") which is already upstream. So which is it? Should we zap this version in tip instead? -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette
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