[PATCH 2/3] KVM: SVM: keep DR6 synchronized with vcpu->arch.dr6

[Paolo Bonzini]

Ensure that the current value of DR6 is always available in vcpu->arch.dr6,
so that the get_dr6 callback can just access vcpu->arch.dr6 and becomes
redundant.

Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
 arch/x86/kvm/svm/svm.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index dbcf4198a9fe..6b65c75b6816 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1654,7 +1654,7 @@ static void new_asid(struct vcpu_svm *svm, struct 
svm_cpu_data *sd)
 
 static u64 svm_get_dr6(struct kvm_vcpu *vcpu)
 {
-       return to_svm(vcpu)->vmcb->save.dr6;
+       return vcpu->arch.dr6;
 }
 
 static void svm_set_dr6(struct kvm_vcpu *vcpu, unsigned long value)
@@ -1673,7 +1673,7 @@ static void svm_sync_dirty_debug_regs(struct kvm_vcpu 
*vcpu)
        get_debugreg(vcpu->arch.db[1], 1);
        get_debugreg(vcpu->arch.db[2], 2);
        get_debugreg(vcpu->arch.db[3], 3);
-       vcpu->arch.dr6 = svm_get_dr6(vcpu);
+       vcpu->arch.dr6 = svm->vmcb->save.dr6;
        vcpu->arch.dr7 = svm->vmcb->save.dr7;
 
        vcpu->arch.switch_db_regs &= ~KVM_DEBUGREG_WONT_EXIT;
@@ -1719,6 +1719,7 @@ static int db_interception(struct vcpu_svm *svm)
        if (!(svm->vcpu.guest_debug &
              (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP)) &&
                !svm->nmi_singlestep) {
+               vcpu->arch.dr6 = svm->vmcb->save.dr6;
                kvm_queue_exception(&svm->vcpu, DB_VECTOR);
                return 1;
        }
-- 
2.18.2