Merge branch 'kvm-fixes-6.10-1' into HEAD

* Fixes and debugging help for the #VE sanity check.  Also disable
  it by default, even for CONFIG_DEBUG_KERNEL, because it was found
  to trigger spuriously (most likely a processor erratum as the
  exact symptoms vary by generation).

* Avoid WARN() when two NMIs arrive simultaneously during an NMI-disabled
  situation (GIF=0 or interrupt shadow) when the processor supports
  virtual NMI.  While generally KVM will not request an NMI window
  when virtual NMIs are supported, in this case it *does* have to
  single-step over the interrupt shadow or enable the STGI intercept,
  in order to deliver the latched second NMI.

* Drop support for hand tuning APIC timer advancement from userspace.
  Since we have adaptive tuning, and it has proved to work well,
  drop the module parameter for manual configuration and with it a
  few stupid bugs that it had.

1 files changed, 14 insertions, 5 deletions

diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c
index 0623cfaa7bb0..95095a233a45 100644
--- a/arch/x86/kvm/svm/sev.c
+++ b/arch/x86/kvm/svm/sev.c
@@ -779,6 +779,14 @@ static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu,
 	 */
 	fpstate_set_confidential(&vcpu->arch.guest_fpu);
 	vcpu->arch.guest_state_protected = true;
+
+	/*
+	 * SEV-ES guest mandates LBR Virtualization to be _always_ ON. Enable it
+	 * only after setting guest_state_protected because KVM_SET_MSRS allows
+	 * dynamic toggling of LBRV (for performance reason) on write access to
+	 * MSR_IA32_DEBUGCTLMSR when guest_state_protected is not set.
+	 */
+	svm_enable_lbrv(vcpu);
 	return 0;
 }
 
@@ -2406,6 +2414,12 @@ void __init sev_hardware_setup(void)
 	if (!boot_cpu_has(X86_FEATURE_SEV_ES))
 		goto out;
 
+	if (!lbrv) {
+		WARN_ONCE(!boot_cpu_has(X86_FEATURE_LBRV),
+			  "LBRV must be present for SEV-ES support");
+		goto out;
+	}
+
 	/* Has the system been allocated ASIDs for SEV-ES? */
 	if (min_sev_asid == 1)
 		goto out;
@@ -3216,7 +3230,6 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
 	struct kvm_vcpu *vcpu = &svm->vcpu;
 
 	svm->vmcb->control.nested_ctl |= SVM_NESTED_CTL_SEV_ES_ENABLE;
-	svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK;
 
 	/*
 	 * An SEV-ES guest requires a VMSA area that is a separate from the
@@ -3268,10 +3281,6 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm)
 	/* Clear intercepts on selected MSRs */
 	set_msr_interception(vcpu, svm->msrpm, MSR_EFER, 1, 1);
 	set_msr_interception(vcpu, svm->msrpm, MSR_IA32_CR_PAT, 1, 1);
-	set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 1, 1);
-	set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 1, 1);
-	set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 1, 1);
-	set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 1, 1);
 }
 
 void sev_init_vmcb(struct vcpu_svm *svm)