4 files changed, 21 insertions, 8 deletions
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c
index aec16e581f5b..5692e827afef 100644
--- a/arch/x86/events/amd/core.c
+++ b/arch/x86/events/amd/core.c
@@ -904,8 +904,8 @@ static int amd_pmu_v2_handle_irq(struct pt_regs *regs)
 	if (!status)
 		goto done;
 
-	/* Read branch records before unfreezing */
-	if (status & GLOBAL_STATUS_LBRS_FROZEN) {
+	/* Read branch records */
+	if (x86_pmu.lbr_nr) {
 		amd_pmu_lbr_read();
 		status &= ~GLOBAL_STATUS_LBRS_FROZEN;
 	}
diff --git a/arch/x86/events/amd/lbr.c b/arch/x86/events/amd/lbr.c
index 4a1e600314d5..5149830c7c4f 100644
--- a/arch/x86/events/amd/lbr.c
+++ b/arch/x86/events/amd/lbr.c
@@ -402,10 +402,12 @@ void amd_pmu_lbr_enable_all(void)
 		wrmsrl(MSR_AMD64_LBR_SELECT, lbr_select);
 	}
 
-	rdmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl);
-	rdmsrl(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg);
+	if (cpu_feature_enabled(X86_FEATURE_AMD_LBR_PMC_FREEZE)) {
+		rdmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl);
+		wrmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
+	}
 
-	wrmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl | DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
+	rdmsrl(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg);
 	wrmsrl(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg | DBG_EXTN_CFG_LBRV2EN);
 }
 
@@ -418,10 +420,12 @@ void amd_pmu_lbr_disable_all(void)
 		return;
 
 	rdmsrl(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg);
-	rdmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl);
-
 	wrmsrl(MSR_AMD_DBG_EXTN_CFG, dbg_extn_cfg & ~DBG_EXTN_CFG_LBRV2EN);
-	wrmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl & ~DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
+
+	if (cpu_feature_enabled(X86_FEATURE_AMD_LBR_PMC_FREEZE)) {
+		rdmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl);
+		wrmsrl(MSR_IA32_DEBUGCTLMSR, dbg_ctl & ~DEBUGCTLMSR_FREEZE_LBRS_ON_PMI);
+	}
 }
 
 __init int amd_pmu_lbr_init(void)
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 4d850a780f7e..a38f8f9ba657 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -460,6 +460,14 @@
 #define X86_FEATURE_SRSO_NO		(20*32+29) /* "" CPU is not affected by SRSO */
 
 /*
+ * Extended auxiliary flags: Linux defined - for features scattered in various
+ * CPUID levels like 0x80000022, etc.
+ *
+ * Reuse free bits when adding new feature flags!
+ */
+#define X86_FEATURE_AMD_LBR_PMC_FREEZE	(21*32+ 0) /* AMD LBR and PMC Freeze */
+
+/*
  * BUG word(s)
  */
 #define X86_BUG(x)			(NCAPINTS*32 + (x))
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 0dad49a09b7a..a515328d9d7d 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -49,6 +49,7 @@ static const struct cpuid_bit cpuid_bits[] = {
 	{ X86_FEATURE_BMEC,		CPUID_EBX,  3, 0x80000020, 0 },
 	{ X86_FEATURE_PERFMON_V2,	CPUID_EAX,  0, 0x80000022, 0 },
 	{ X86_FEATURE_AMD_LBR_V2,	CPUID_EAX,  1, 0x80000022, 0 },
+	{ X86_FEATURE_AMD_LBR_PMC_FREEZE,	CPUID_EAX,  2, 0x80000022, 0 },
 	{ 0, 0, 0, 0, 0 }
 };