KVM: x86 emulator: do not inject exception directly into vcpu

Return exception as a result of instruction emulation and handle
injection in KVM code.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

1 files changed, 17 insertions, 3 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 91bfe7771f50..63c87adcec48 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3852,6 +3852,17 @@ static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask)
                 kvm_x86_ops->set_interrupt_shadow(vcpu, mask);
 }
 
+static void inject_emulated_exception(struct kvm_vcpu *vcpu)
+{
+        struct x86_emulate_ctxt *ctxt = &vcpu->arch.emulate_ctxt;
+        if (ctxt->exception == PF_VECTOR)
+                kvm_inject_page_fault(vcpu, ctxt->cr2, ctxt->error_code);
+        else if (ctxt->error_code_valid)
+                kvm_queue_exception_e(vcpu, ctxt->exception, ctxt->error_code);
+        else
+                kvm_queue_exception(vcpu, ctxt->exception);
+}
+
 int emulate_instruction(struct kvm_vcpu *vcpu,
                         unsigned long cr2,
                         u16 error_code,
@@ -3886,6 +3897,7 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
                 memset(c, 0, sizeof(struct decode_cache));
                 memcpy(c->regs, vcpu->arch.regs, sizeof c->regs);
                 vcpu->arch.emulate_ctxt.interruptibility = 0;
+                vcpu->arch.emulate_ctxt.exception = -1;
 
                 r = x86_decode_insn(&vcpu->arch.emulate_ctxt, &emulate_ops);
                 trace_kvm_emulate_insn_start(vcpu);
@@ -3958,6 +3970,11 @@ restart:
         memcpy(vcpu->arch.regs, c->regs, sizeof c->regs);
         kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.eip);
 
+        if (vcpu->arch.emulate_ctxt.exception >= 0) {
+                inject_emulated_exception(vcpu);
+                return EMULATE_DONE;
+        }
+
         if (vcpu->arch.pio.count) {
                 if (!vcpu->arch.pio.in)
                         vcpu->arch.pio.count = 0;
@@ -3970,9 +3987,6 @@ restart:
                 return EMULATE_DO_MMIO;
         }
 
-        if (vcpu->arch.exception.pending)
-                vcpu->arch.emulate_ctxt.restart = false;
-
         if (vcpu->arch.emulate_ctxt.restart)
                 goto restart;