From: Avi Kivity <avi@redhat.com>
Date: Sun, 25 Jul 2010 11:51:16 +0000 (+0300)
Subject: KVM: x86 emulator: fix handling for unemulated instructions
X-Git-Tag: v2.6.37-rc1~142^2~320
X-Git-Url: https://openfabrics.org/gitweb/?a=commitdiff_plain;h=91269b8f94eedce1767b2f208d656e5a5683326a;p=~shefty%2Frdma-dev.git

KVM: x86 emulator: fix handling for unemulated instructions

If an instruction is present in the decode tables but not in the execution
switch, it will be emulated as a NOP.  An example is IRET (0xcf).

Fix by adding default: labels to the execution switches.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 66ca98aafdd..70e47d3593d 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3028,6 +3028,8 @@ special_insn:
 		if (c->modrm_reg == 5)
 			goto jump_far;
 		goto grp45;
+	default:
+		goto cannot_emulate;
 	}
 
 writeback:
@@ -3353,6 +3355,8 @@ twobyte_insn:
 		if (rc != X86EMUL_CONTINUE)
 			goto done;
 		break;
+	default:
+		goto cannot_emulate;
 	}
 	goto writeback;