The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y git checkout FETCH_HEAD git cherry-pick -x 68e61f6fd65610e73b17882f86fedfd784d99229 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025101537-entangled-rhyme-6714@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 68e61f6fd65610e73b17882f86fedfd784d99229 Mon Sep 17 00:00:00 2001 From: Sean Christopherson seanjc@google.com Date: Fri, 11 Jul 2025 10:27:46 -0700 Subject: [PATCH] KVM: SVM: Emulate PERF_CNTR_GLOBAL_STATUS_SET for PerfMonV2

Emulate PERF_CNTR_GLOBAL_STATUS_SET when PerfMonV2 is enumerated to the guest, as the MSR is supposed to exist in all AMD v2 PMUs.

Fixes: 4a2771895ca6 ("KVM: x86/svm/pmu: Add AMD PerfMonV2 support") Cc: stable@vger.kernel.org Cc: Sandipan Das sandipan.das@amd.com Link: https://lore.kernel.org/r/20250711172746.1579423-1-seanjc@google.com Signed-off-by: Sean Christopherson seanjc@google.com

diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index b65c3ba5fa14..20fa4a79df13 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -733,6 +733,7 @@ #define MSR_AMD64_PERF_CNTR_GLOBAL_STATUS 0xc0000300 #define MSR_AMD64_PERF_CNTR_GLOBAL_CTL 0xc0000301 #define MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR 0xc0000302 +#define MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_SET 0xc0000303

/* AMD Hardware Feedback Support MSRs */ #define MSR_AMD_WORKLOAD_CLASS_CONFIG 0xc0000500 diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index 75e9cfc689f8..a84fb3d28885 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -650,6 +650,7 @@ int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) msr_info->data = pmu->global_ctrl; break; case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR: + case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_SET: case MSR_CORE_PERF_GLOBAL_OVF_CTRL: msr_info->data = 0; break; @@ -711,6 +712,10 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) if (!msr_info->host_initiated) pmu->global_status &= ~data; break; + case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_SET: + if (!msr_info->host_initiated) + pmu->global_status |= data & ~pmu->global_status_rsvd; + break; default: kvm_pmu_mark_pmc_in_use(vcpu, msr_info->index); return kvm_pmu_call(set_msr)(vcpu, msr_info); diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c index 288f7f2a46f2..aa4379e46e96 100644 --- a/arch/x86/kvm/svm/pmu.c +++ b/arch/x86/kvm/svm/pmu.c @@ -113,6 +113,7 @@ static bool amd_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr) case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS: case MSR_AMD64_PERF_CNTR_GLOBAL_CTL: case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR: + case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_SET: return pmu->version > 1; default: if (msr > MSR_F15H_PERF_CTR5 && diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 79057622fa76..5dc32f2fe391 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -367,6 +367,7 @@ static const u32 msrs_to_save_pmu[] = { MSR_AMD64_PERF_CNTR_GLOBAL_CTL, MSR_AMD64_PERF_CNTR_GLOBAL_STATUS, MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR, + MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_SET, };

static u32 msrs_to_save[ARRAY_SIZE(msrs_to_save_base) + @@ -7353,6 +7354,7 @@ static void kvm_probe_msr_to_save(u32 msr_index) case MSR_AMD64_PERF_CNTR_GLOBAL_CTL: case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS: case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR: + case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_SET: if (!kvm_cpu_cap_has(X86_FEATURE_PERFMON_V2)) return; break;