KVM: x86 emulator: introduce NoWrite flag
Instead of disabling writeback via OP_NONE, just specify NoWrite.
Acked-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi.kivity@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 42c53c80..fe113fb 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -151,6 +151,7 @@
#define Unaligned ((u64)1 << 42) /* Explicitly unaligned (e.g. MOVDQU) */
#define Avx ((u64)1 << 43) /* Advanced Vector Extensions */
#define Fastop ((u64)1 << 44) /* Use opcode::u.fastop */
+#define NoWrite ((u64)1 << 45) /* No writeback */
#define X2(x...) x, x
#define X3(x...) X2(x), x
@@ -1633,6 +1634,9 @@
{
int rc;
+ if (ctxt->d & NoWrite)
+ return X86EMUL_CONTINUE;
+
switch (ctxt->dst.type) {
case OP_REG:
write_register_operand(&ctxt->dst);