[PATCH 6.12] KVM: SVM: Set synthesized TSA CPUID flags

[PATCH 6.12] KVM: SVM: Set synthesized TSA CPUID flags

[Borislav Petkov]

From: "Borislav Petkov (AMD)" <bp@alien8.de>

VERW_CLEAR is supposed to be set only by the hypervisor to denote TSA
mitigation support to a guest. SQ_NO and L1_NO are both synthesizable,
and are going to be set by hw CPUID on future machines.

So keep the kvm_cpu_cap_init_kvm_defined() invocation *and* set them
when synthesized.

This fix is stable-only.

Co-developed-by: Jinpu Wang <jinpu.wang@ionos.com>
Signed-off-by: Jinpu Wang <jinpu.wang@ionos.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
---
 arch/x86/kvm/cpuid.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 02196db26a08..8f587c5bb6bc 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -822,6 +822,7 @@ void kvm_set_cpu_caps(void)
 	kvm_cpu_cap_check_and_set(X86_FEATURE_SBPB);
 	kvm_cpu_cap_check_and_set(X86_FEATURE_IBPB_BRTYPE);
 	kvm_cpu_cap_check_and_set(X86_FEATURE_SRSO_NO);
+	kvm_cpu_cap_check_and_set(X86_FEATURE_VERW_CLEAR);
 
 	kvm_cpu_cap_init_kvm_defined(CPUID_8000_0022_EAX,
 		F(PERFMON_V2)
@@ -831,6 +832,9 @@ void kvm_set_cpu_caps(void)
 		F(TSA_SQ_NO) | F(TSA_L1_NO)
 	);
 
+	kvm_cpu_cap_check_and_set(X86_FEATURE_TSA_SQ_NO);
+	kvm_cpu_cap_check_and_set(X86_FEATURE_TSA_L1_NO);
+
 	/*
 	 * Synthesize "LFENCE is serializing" into the AMD-defined entry in
 	 * KVM's supported CPUID if the feature is reported as supported by the
-- 
2.43.0