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From:   Kim Phillips <kim.phillips@amd.com>
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Subject: [PATCH v9 3/8] x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature
Date:   Tue, 24 Jan 2023 10:33:14 -0600
Message-ID: <20230124163319.2277355-4-kim.phillips@amd.com>
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The "Processor ignores nested data breakpoints" feature was being
open-coded for KVM.  Add the feature to its newly introduced
CPUID leaf 0x80000021 EAX proper.

Signed-off-by: Kim Phillips <kim.phillips@amd.com>
---
 arch/x86/include/asm/cpufeatures.h | 3 +++
 arch/x86/kvm/cpuid.c               | 2 +-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 552bd3943370..4637fd7a84d6 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -430,6 +430,9 @@
 #define X86_FEATURE_V_TSC_AUX		(19*32+ 9) /* "" Virtual TSC_AUX */
 #define X86_FEATURE_SME_COHERENT	(19*32+10) /* "" AMD hardware-enforced cache coherency */
 
+/* AMD-defined Extended Feature 2 EAX, CPUID level 0x80000021 (EAX), word 20 */
+#define X86_FEATURE_NO_NESTED_DATA_BP	(20*32+ 0) /* "" No Nested Data Breakpoints */
+
 /*
  * BUG word(s)
  */
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index a1047763fdd3..9764499acce2 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -742,7 +742,7 @@ void kvm_set_cpu_caps(void)
 		F(SME_COHERENT));
 
 	kvm_cpu_cap_mask(CPUID_8000_0021_EAX,
-		BIT(0) /* NO_NESTED_DATA_BP */ |
+		F(NO_NESTED_DATA_BP) |
 		BIT(2) /* LFENCE Always serializing */ | 0 /* SmmPgCfgLock */ |
 		BIT(6) /* NULL_SEL_CLR_BASE */ | 0 /* PrefetchCtlMsr */
 	);
-- 
2.34.1