diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2013-05-09 11:32:51 +0200 |
|---|---|---|
| committer | Gleb Natapov <gleb@redhat.com> | 2013-05-09 13:15:08 +0300 |
| commit | 326f578f7e1443bac2333712dd130a261ec15288 (patch) | |
| tree | 7d1e6123f831b6789f68d4e9ea0f7f10a904230b /arch/x86/kvm/emulate.c | |
| parent | 7fa57952d70f5737513d8319395e471d107e4e0d (diff) | |
KVM: emulator: emulate SALC
This is an almost-undocumented instruction available in 32-bit mode.
I say "almost" undocumented because AMD documents it in their opcode
maps just to say that it is unavailable in 64-bit mode (sections
"A.2.1 One-Byte Opcodes" and "B.3 Invalid and Reassigned Instructions
in 64-Bit Mode").
It is roughly equivalent to "sbb %al, %al" except it does not
set the flags. Use fastop to emulate it, but do not use the opcode
directly because it would fail if the host is 64-bit!
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Diffstat (limited to 'arch/x86/kvm/emulate.c')
| -rw-r--r-- | arch/x86/kvm/emulate.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a06a550c2db..8db0010ed15 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -535,6 +535,9 @@ FOP_SETCC(setle) FOP_SETCC(setnle) FOP_END; +FOP_START(salc) "pushf; sbb %al, %al; popf \n\t" FOP_RET +FOP_END; + #define __emulate_1op_rax_rdx(ctxt, _op, _suffix, _ex) \ do { \ unsigned long _tmp; \ @@ -3961,7 +3964,8 @@ static const struct opcode opcode_table[256] = { G(Src2One | ByteOp, group2), G(Src2One, group2), G(Src2CL | ByteOp, group2), G(Src2CL, group2), I(DstAcc | SrcImmUByte | No64, em_aam), - I(DstAcc | SrcImmUByte | No64, em_aad), N, + I(DstAcc | SrcImmUByte | No64, em_aad), + F(DstAcc | ByteOp | No64, em_salc), I(DstAcc | SrcXLat | ByteOp, em_mov), /* 0xD8 - 0xDF */ N, E(0, &escape_d9), N, E(0, &escape_db), N, E(0, &escape_dd), N, N, |