| Message ID | 1422257547-4557-3-git-send-email-namit@cs.technion.ac.il (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index aa27254..dd71004 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -4062,8 +4062,8 @@ static const struct opcode opcode_table[256] = { G(ByteOp, group11), G(0, group11), /* 0xC8 - 0xCF */ I(Stack | SrcImmU16 | Src2ImmByte, em_enter), I(Stack, em_leave), - I(ImplicitOps | Stack | SrcImmU16, em_ret_far_imm), - I(ImplicitOps | Stack, em_ret_far), + I(ImplicitOps | SrcImmU16, em_ret_far_imm), + I(ImplicitOps, em_ret_far), D(ImplicitOps), DI(SrcImmByte, intn), D(ImplicitOps | No64), II(ImplicitOps, em_iret, iret), /* 0xD0 - 0xD7 */
Indeed, Intel SDM specifically states that for the RET instruction "In 64-bit mode, the default operation size of this instruction is the stack-address size, i.e. 64 bits." However, experiments show this is not the case. Here is for example objdump of small 64-bit asm: 4004f1: ca 14 00 lret $0x14 4004f4: 48 cb lretq 4004f6: 48 ca 14 00 lretq $0x14 Therefore, remove the Stack flag from far-ret instructions. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> --- arch/x86/kvm/emulate.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)