1 files changed, 48 insertions, 2 deletions

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 0fbbde54ecae..88d9062f4545 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -968,9 +968,32 @@ static void svm_set_segment(struct kvm_vcpu *vcpu,
 
 }
 
-static int svm_guest_debug(struct kvm_vcpu *vcpu, struct kvm_debug_guest *dbg)
+static int svm_guest_debug(struct kvm_vcpu *vcpu, struct kvm_guest_debug *dbg)
 {
-        return -EOPNOTSUPP;
+        int old_debug = vcpu->guest_debug;
+        struct vcpu_svm *svm = to_svm(vcpu);
+
+        vcpu->guest_debug = dbg->control;
+
+        svm->vmcb->control.intercept_exceptions &=
+                ~((1 << DB_VECTOR) | (1 << BP_VECTOR));
+        if (vcpu->guest_debug & KVM_GUESTDBG_ENABLE) {
+                if (vcpu->guest_debug &
+                    (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))
+                        svm->vmcb->control.intercept_exceptions |=
+                                1 << DB_VECTOR;
+                if (vcpu->guest_debug & KVM_GUESTDBG_USE_SW_BP)
+                        svm->vmcb->control.intercept_exceptions |=
+                                1 << BP_VECTOR;
+        } else
+                vcpu->guest_debug = 0;
+
+        if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
+                svm->vmcb->save.rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
+        else if (old_debug & KVM_GUESTDBG_SINGLESTEP)
+                svm->vmcb->save.rflags &= ~(X86_EFLAGS_TF | X86_EFLAGS_RF);
+
+        return 0;
 }
 
 static int svm_get_irq(struct kvm_vcpu *vcpu)
@@ -1094,6 +1117,27 @@ static int pf_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
         return kvm_mmu_page_fault(&svm->vcpu, fault_address, error_code);
 }
 
+static int db_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
+{
+        if (!(svm->vcpu.guest_debug &
+              (KVM_GUESTDBG_SINGLESTEP | KVM_GUESTDBG_USE_HW_BP))) {
+                kvm_queue_exception(&svm->vcpu, DB_VECTOR);
+                return 1;
+        }
+        kvm_run->exit_reason = KVM_EXIT_DEBUG;
+        kvm_run->debug.arch.pc = svm->vmcb->save.cs.base + svm->vmcb->save.rip;
+        kvm_run->debug.arch.exception = DB_VECTOR;
+        return 0;
+}
+
+static int bp_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
+{
+        kvm_run->exit_reason = KVM_EXIT_DEBUG;
+        kvm_run->debug.arch.pc = svm->vmcb->save.cs.base + svm->vmcb->save.rip;
+        kvm_run->debug.arch.exception = BP_VECTOR;
+        return 0;
+}
+
 static int ud_interception(struct vcpu_svm *svm, struct kvm_run *kvm_run)
 {
         int er;
@@ -2050,6 +2094,8 @@ static int (*svm_exit_handlers[])(struct vcpu_svm *svm,
         [SVM_EXIT_WRITE_DR3]                    = emulate_on_interception,
         [SVM_EXIT_WRITE_DR5]                    = emulate_on_interception,
         [SVM_EXIT_WRITE_DR7]                    = emulate_on_interception,
+        [SVM_EXIT_EXCP_BASE + DB_VECTOR]        = db_interception,
+        [SVM_EXIT_EXCP_BASE + BP_VECTOR]        = bp_interception,
         [SVM_EXIT_EXCP_BASE + UD_VECTOR]        = ud_interception,
         [SVM_EXIT_EXCP_BASE + PF_VECTOR]        = pf_interception,
         [SVM_EXIT_EXCP_BASE + NM_VECTOR]        = nm_interception,