6.6-stable review patch. If anyone has any objections, please let me know.
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From: Yosry Ahmed yosry.ahmed@linux.dev
Introduce a helper updating the intercepts for LBR MSRs, similar to the one introduced upstream by commit 160f143cc131 ("KVM: SVM: Manually recalc all MSR intercepts on userspace MSR filter change"). The main difference is that this version uses set_msr_interception(), which has inverted polarity compared to svm_set_intercept_for_msr().
This is intended to simplify incoming backports. No functional changes intended.
Signed-off-by: Yosry Ahmed yosry.ahmed@linux.dev Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/x86/kvm/svm/svm.c | 32 +++++++++++++++++++++----------- 1 file changed, 21 insertions(+), 11 deletions(-)
--- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -1012,18 +1012,31 @@ void svm_copy_lbrs(struct vmcb *to_vmcb, vmcb_mark_dirty(to_vmcb, VMCB_LBR); }
-void svm_enable_lbrv(struct kvm_vcpu *vcpu) +static void svm_recalc_lbr_msr_intercepts(struct kvm_vcpu *vcpu) { struct vcpu_svm *svm = to_svm(vcpu); + bool intercept = !(svm->vmcb->control.virt_ext & LBR_CTL_ENABLE_MASK);
- svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; - 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); + set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, + !intercept, !intercept); + set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, + !intercept, !intercept); + set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, + !intercept, !intercept); + set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, + !intercept, !intercept);
if (sev_es_guest(vcpu->kvm)) - set_msr_interception(vcpu, svm->msrpm, MSR_IA32_DEBUGCTLMSR, 1, 1); + set_msr_interception(vcpu, svm->msrpm, MSR_IA32_DEBUGCTLMSR, + !intercept, !intercept); +} + +void svm_enable_lbrv(struct kvm_vcpu *vcpu) +{ + struct vcpu_svm *svm = to_svm(vcpu); + + svm->vmcb->control.virt_ext |= LBR_CTL_ENABLE_MASK; + svm_recalc_lbr_msr_intercepts(vcpu);
/* Move the LBR msrs to the vmcb02 so that the guest can see them. */ if (is_guest_mode(vcpu)) @@ -1037,10 +1050,7 @@ static void svm_disable_lbrv(struct kvm_ KVM_BUG_ON(sev_es_guest(vcpu->kvm), vcpu->kvm);
svm->vmcb->control.virt_ext &= ~LBR_CTL_ENABLE_MASK; - set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHFROMIP, 0, 0); - set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTBRANCHTOIP, 0, 0); - set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTFROMIP, 0, 0); - set_msr_interception(vcpu, svm->msrpm, MSR_IA32_LASTINTTOIP, 0, 0); + svm_recalc_lbr_msr_intercepts(vcpu);
/* * Move the LBR msrs back to the vmcb01 to avoid copying them