diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2013-05-09 11:32:49 +0200 |
|---|---|---|
| committer | Gleb Natapov <gleb@redhat.com> | 2013-05-09 13:12:58 +0300 |
| commit | a035d5c64d08a8ac12d81b596e7fa6d95a73c347 (patch) | |
| tree | d294150c9d50c711d48e9d2e1827b4dde7c316ec | |
| parent | 8d76c49e9ffeee839bc0b7a3278a23f99101263e (diff) | |
| download | linux-a035d5c64d08a8ac12d81b596e7fa6d95a73c347.tar.bz2 | |
KVM: emulator: emulate AAM
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
AAM needs the source operand to be unsigned; do the same in AAD as well
for consistency, even though it does not affect the result.
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>
| -rw-r--r-- | arch/x86/kvm/emulate.c | 25 |
1 files changed, 24 insertions, 1 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 8e517bba6a7c..55322a7c113d 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2996,6 +2996,28 @@ static int em_das(struct x86_emulate_ctxt *ctxt) return X86EMUL_CONTINUE; } +static int em_aam(struct x86_emulate_ctxt *ctxt) +{ + u8 al, ah; + + if (ctxt->src.val == 0) + return emulate_de(ctxt); + + al = ctxt->dst.val & 0xff; + ah = al / ctxt->src.val; + al %= ctxt->src.val; + + ctxt->dst.val = (ctxt->dst.val & 0xffff0000) | al | (ah << 8); + + /* Set PF, ZF, SF */ + ctxt->src.type = OP_IMM; + ctxt->src.val = 0; + ctxt->src.bytes = 1; + fastop(ctxt, em_or); + + return X86EMUL_CONTINUE; +} + static int em_aad(struct x86_emulate_ctxt *ctxt) { u8 al = ctxt->dst.val & 0xff; @@ -3936,7 +3958,8 @@ static const struct opcode opcode_table[256] = { /* 0xD0 - 0xD7 */ G(Src2One | ByteOp, group2), G(Src2One, group2), G(Src2CL | ByteOp, group2), G(Src2CL, group2), - N, I(DstAcc | SrcImmByte | No64, em_aad), N, N, + I(DstAcc | SrcImmUByte | No64, em_aam), + I(DstAcc | SrcImmUByte | No64, em_aad), N, N, /* 0xD8 - 0xDF */ N, E(0, &escape_d9), N, E(0, &escape_db), N, E(0, &escape_dd), N, N, /* 0xE0 - 0xE7 */ |