| From a035d5c64d08a8ac12d81b596e7fa6d95a73c347 Mon Sep 17 00:00:00 2001 |
| From: Paolo Bonzini <pbonzini@redhat.com> |
| Date: Thu, 9 May 2013 11:32:49 +0200 |
| Subject: KVM: emulator: emulate AAM |
| |
| From: Paolo Bonzini <pbonzini@redhat.com> |
| |
| commit a035d5c64d08a8ac12d81b596e7fa6d95a73c347 upstream. |
| |
| 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> |
| Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
| Signed-off-by: Gleb Natapov <gleb@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/kvm/emulate.c | 25 ++++++++++++++++++++++++- |
| 1 file changed, 24 insertions(+), 1 deletion(-) |
| |
| --- a/arch/x86/kvm/emulate.c |
| +++ b/arch/x86/kvm/emulate.c |
| @@ -2986,6 +2986,28 @@ static int em_das(struct x86_emulate_ctx |
| 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; |
| @@ -3926,7 +3948,8 @@ static const struct opcode opcode_table[ |
| /* 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 */ |