From 0b789eee2c0204da83278f181428560faf6efefb Mon Sep 17 00:00:00 2001
From: Gleb Natapov <gleb@redhat.com>
Date: Thu, 11 Apr 2013 11:59:55 +0300
Subject: [PATCH] KVM: emulator: fix unimplemented instruction detection
Unimplemented instruction detection is broken for group instructions
since it relies on "flags" field of opcode to be zero, but all
instructions in a group inherit flags from a group encoding. Fix that by
having a separate flag for unimplemented instructions.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
---
arch/x86/kvm/emulate.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 069d79926e2b3..ab6fda4eb98f4 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -132,8 +132,9 @@
#define Priv (1<<27) /* instruction generates #GP if current CPL != 0 */
#define No64 (1<<28)
#define PageTable (1 << 29) /* instruction used to write page table */
+#define NotImpl (1 << 30) /* instruction is not implemented */
/* Source 2 operand type */
-#define Src2Shift (30)
+#define Src2Shift (31)
#define Src2None (OpNone << Src2Shift)
#define Src2CL (OpCL << Src2Shift)
#define Src2ImmByte (OpImmByte << Src2Shift)
@@ -3624,7 +3625,7 @@ static int check_perm_out(struct x86_emulate_ctxt *ctxt)
#define DI(_y, _i) { .flags = (_y), .intercept = x86_intercept_##_i }
#define DIP(_y, _i, _p) { .flags = (_y), .intercept = x86_intercept_##_i, \
.check_perm = (_p) }
-#define N D(0)
+#define N D(NotImpl)
#define EXT(_f, _e) { .flags = ((_f) | RMExt), .u.group = (_e) }
#define G(_f, _g) { .flags = ((_f) | Group | ModRM), .u.group = (_g) }
#define GD(_f, _g) { .flags = ((_f) | GroupDual | ModRM), .u.gdual = (_g) }
@@ -4382,7 +4383,7 @@ int x86_decode_insn(struct x86_emulate_ctxt *ctxt, void *insn, int insn_len)
ctxt->intercept = opcode.intercept;
/* Unrecognised? */
- if (ctxt->d == 0 || (ctxt->d & Undefined))
+ if (ctxt->d == 0 || (ctxt->d & NotImpl) || (ctxt->d & Undefined))
return EMULATION_FAILED;
if (!(ctxt->d & VendorSpecific) && ctxt->only_vendor_specific_insn)
--
GitLab