KVM: x86 emulator: Fix stack instructions on 64-bit mode

Stack instructions are always 64-bit on 64-bit mode; many of the
emulated stack instructions did not take that into account.  Fix by
adding a 'Stack' bitflag and setting the operand size appropriately
during the decode stage (except for 'push r/m', which is in a group
with a few other instructions, so it gets its own treatment).

This fixes random crashes on Vista x64.

Signed-off-by: Avi Kivity <avi@qumranet.com>
This commit is contained in:
Avi Kivity 2007-12-06 18:14:14 +02:00
parent 152ff9be2e
commit 6e3d5dfbad
1 changed files with 15 additions and 12 deletions

View File

@ -65,6 +65,7 @@
#define BitOp (1<<8)
#define MemAbs (1<<9) /* Memory operand is absolute displacement */
#define String (1<<10) /* String instruction (rep capable) */
#define Stack (1<<11) /* Stack instruction (push/pop) */
static u16 opcode_table[256] = {
/* 0x00 - 0x07 */
@ -104,14 +105,16 @@ static u16 opcode_table[256] = {
/* 0x48 - 0x4F */
DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg,
/* 0x50 - 0x57 */
SrcReg, SrcReg, SrcReg, SrcReg, SrcReg, SrcReg, SrcReg, SrcReg,
SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, SrcReg | Stack,
SrcReg | Stack, SrcReg | Stack, SrcReg | Stack, SrcReg | Stack,
/* 0x58 - 0x5F */
DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg, DstReg,
DstReg | Stack, DstReg | Stack, DstReg | Stack, DstReg | Stack,
DstReg | Stack, DstReg | Stack, DstReg | Stack, DstReg | Stack,
/* 0x60 - 0x67 */
0, 0, 0, DstReg | SrcMem32 | ModRM | Mov /* movsxd (x86/64) */ ,
0, 0, 0, 0,
/* 0x68 - 0x6F */
0, 0, ImplicitOps|Mov, 0,
0, 0, ImplicitOps | Mov | Stack, 0,
SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* insb, insw/insd */
SrcNone | ByteOp | ImplicitOps, SrcNone | ImplicitOps, /* outsb, outsw/outsd */
/* 0x70 - 0x77 */
@ -128,9 +131,10 @@ static u16 opcode_table[256] = {
/* 0x88 - 0x8F */
ByteOp | DstMem | SrcReg | ModRM | Mov, DstMem | SrcReg | ModRM | Mov,
ByteOp | DstReg | SrcMem | ModRM | Mov, DstReg | SrcMem | ModRM | Mov,
0, ModRM | DstReg, 0, DstMem | SrcNone | ModRM | Mov,
0, ModRM | DstReg, 0, DstMem | SrcNone | ModRM | Mov | Stack,
/* 0x90 - 0x9F */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ImplicitOps, ImplicitOps, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, ImplicitOps | Stack, ImplicitOps | Stack, 0, 0,
/* 0xA0 - 0xA7 */
ByteOp | DstReg | SrcMem | Mov | MemAbs, DstReg | SrcMem | Mov | MemAbs,
ByteOp | DstMem | SrcReg | Mov | MemAbs, DstMem | SrcReg | Mov | MemAbs,
@ -144,7 +148,7 @@ static u16 opcode_table[256] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
/* 0xC0 - 0xC7 */
ByteOp | DstMem | SrcImm | ModRM, DstMem | SrcImmByte | ModRM,
0, ImplicitOps, 0, 0,
0, ImplicitOps | Stack, 0, 0,
ByteOp | DstMem | SrcImm | ModRM | Mov, DstMem | SrcImm | ModRM | Mov,
/* 0xC8 - 0xCF */
0, 0, 0, 0, 0, 0, 0, 0,
@ -157,7 +161,8 @@ static u16 opcode_table[256] = {
/* 0xE0 - 0xE7 */
0, 0, 0, 0, 0, 0, 0, 0,
/* 0xE8 - 0xEF */
ImplicitOps, SrcImm|ImplicitOps, 0, SrcImmByte|ImplicitOps, 0, 0, 0, 0,
ImplicitOps | Stack, SrcImm|ImplicitOps, 0, SrcImmByte|ImplicitOps,
0, 0, 0, 0,
/* 0xF0 - 0xF7 */
0, 0, 0, 0,
ImplicitOps, ImplicitOps,
@ -868,6 +873,9 @@ x86_decode_insn(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops)
}
}
if (mode == X86EMUL_MODE_PROT64 && (c->d & Stack))
c->op_bytes = 8;
/* ModRM and SIB bytes. */
if (c->d & ModRM)
rc = decode_modrm(ctxt, ops);
@ -988,11 +996,6 @@ static inline int emulate_grp1a(struct x86_emulate_ctxt *ctxt,
struct decode_cache *c = &ctxt->decode;
int rc;
/* 64-bit mode: POP always pops a 64-bit operand. */
if (ctxt->mode == X86EMUL_MODE_PROT64)
c->dst.bytes = 8;
rc = ops->read_std(register_address(ctxt->ss_base,
c->regs[VCPU_REGS_RSP]),
&c->dst.val, c->dst.bytes, ctxt->vcpu);