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-rw-r--r--arch/x86/events/intel/core.c5
-rw-r--r--arch/x86/include/asm/msr-index.h3
2 files changed, 6 insertions, 2 deletions
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index f3d5b718f93f..e86333eee266 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -5042,8 +5042,11 @@ static void intel_pmu_cpu_starting(int cpu)
init_debug_store_on_cpu(cpu);
/*
- * Deal with CPUs that don't clear their LBRs on power-up.
+ * Deal with CPUs that don't clear their LBRs on power-up, and that may
+ * even boot with LBRs enabled.
*/
+ if (!static_cpu_has(X86_FEATURE_ARCH_LBR) && x86_pmu.lbr_nr)
+ msr_clear_bit(MSR_IA32_DEBUGCTLMSR, DEBUGCTLMSR_LBR_BIT);
intel_pmu_lbr_reset();
cpuc->lbr_sel = NULL;
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h
index 9a71880eec07..72765b2fe0d8 100644
--- a/arch/x86/include/asm/msr-index.h
+++ b/arch/x86/include/asm/msr-index.h
@@ -395,7 +395,8 @@
#define MSR_IA32_PASID_VALID BIT_ULL(31)
/* DEBUGCTLMSR bits (others vary by model): */
-#define DEBUGCTLMSR_LBR (1UL << 0) /* last branch recording */
+#define DEBUGCTLMSR_LBR_BIT 0 /* last branch recording */
+#define DEBUGCTLMSR_LBR (1UL << DEBUGCTLMSR_LBR_BIT)
#define DEBUGCTLMSR_BTF_SHIFT 1
#define DEBUGCTLMSR_BTF (1UL << 1) /* single-step on branches */
#define DEBUGCTLMSR_BUS_LOCK_DETECT (1UL << 2)