[PATCH 06/13] KVM: x86: Extend CPUID range to include new leaf

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CPUID leaf 0x8000001b (EAX) provides information about
Instruction-Based sampling capabilities on AMD Platforms. Complete
description about 0x8000001b CPUID leaf is available in AMD
Programmer's Manual volume 3, Appendix E, section E.4.13.
https://bugzilla.kernel.org/attachment.cgi?id=304655

Signed-off-by: Manali Shukla <manali.shukla@xxxxxxx>
---
 arch/x86/kvm/cpuid.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 0544e30b4946..1f4d505fb69d 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -771,6 +771,12 @@ void kvm_set_cpu_caps(void)
 		F(PERFMON_V2)
 	);
 
+	/*
+	 * Hide all IBS related features by default, it will be enabled
+	 * automatically when IBS virtualization is enabled
+	 */
+	kvm_cpu_cap_init_kvm_defined(CPUID_8000_001B_EAX, 0);
+
 	/*
 	 * Synthesize "LFENCE is serializing" into the AMD-defined entry in
 	 * KVM's supported CPUID if the feature is reported as supported by the
@@ -1252,6 +1258,11 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 		entry->eax = entry->ebx = entry->ecx = 0;
 		entry->edx = 0; /* reserved */
 		break;
+	/* AMD IBS capability */
+	case 0x8000001B:
+		entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
+		cpuid_entry_override(entry, CPUID_8000_001B_EAX);
+		break;
 	case 0x8000001F:
 		if (!kvm_cpu_cap_has(X86_FEATURE_SEV)) {
 			entry->eax = entry->ebx = entry->ecx = entry->edx = 0;
-- 
2.34.1




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