From 047a4818094217a1323d8f31f9318ea2e142f745 Mon Sep 17 00:00:00 2001
From: Avi Kivity <avi@redhat.com>
Date: Mon, 26 Jul 2010 14:37:47 +0300
Subject: [PATCH] KVM: x86 emulator: add Undefined decode flag
Add a decode flag to indicate the instruction is invalid. Will come in useful
later, when we mix decode bits from the opcode and group table.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
---
arch/x86/kvm/emulate.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 61139e20b899..b1e3e8c2aff5 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -84,6 +84,7 @@
#define GroupDual (1<<15) /* Alternate decoding of mod == 3 */
#define GroupMask 0x0f /* Group number stored in bits 0:3 */
/* Misc flags */
+#define Undefined (1<<25) /* No Such Instruction */
#define Lock (1<<26) /* lock prefix is allowed for the instruction */
#define Priv (1<<27) /* instruction generates #GP if current CPL != 0 */
#define No64 (1<<28)
@@ -1065,7 +1066,7 @@ done_prefixes:
}
/* Unrecognised? */
- if (c->d == 0) {
+ if (c->d == 0 || (c->d & Undefined)) {
DPRINTF("Cannot emulate %02x\n", c->b);
return -1;
}