KVM: x86 emulator: Add new mode of instruction emulation: skip

In the new mode instruction is decoded, but not executed. The EIP
is moved to point after the instruction.

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

1 files changed, 5 insertions, 0 deletions

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b5ac1b722454..8beccaa17690 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2413,6 +2413,11 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
                 }
         }
 
+        if (emulation_type & EMULTYPE_SKIP) {
+                kvm_rip_write(vcpu, vcpu->arch.emulate_ctxt.decode.eip);
+                return EMULATE_DONE;
+        }
+
         r = x86_emulate_insn(&vcpu->arch.emulate_ctxt, &emulate_ops);
 
         if (vcpu->arch.pio.string)