From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] KVM: emulator: implement AAD instruction Date: Fri, 14 Dec 2012 11:44:22 +0100 Message-ID: <50CB0306.6020909@redhat.com> References: <20121210094230.GI19514@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: kvm@vger.kernel.org, mtosatti@redhat.com To: Gleb Natapov Return-path: Received: from mail-ie0-f174.google.com ([209.85.223.174]:64954 "EHLO mail-ie0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752391Ab2LNKo2 (ORCPT ); Fri, 14 Dec 2012 05:44:28 -0500 Received: by mail-ie0-f174.google.com with SMTP id c11so5582378ieb.19 for ; Fri, 14 Dec 2012 02:44:28 -0800 (PST) In-Reply-To: <20121210094230.GI19514@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: Il 10/12/2012 10:42, Gleb Natapov ha scritto: > Windows2000 uses it during boot. This fixes > https://bugzilla.kernel.org/show_bug.cgi?id=50921 > > Signed-off-by: Gleb Natapov > diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c > index 39171cb..92c7292 100644 > --- a/arch/x86/kvm/emulate.c > +++ b/arch/x86/kvm/emulate.c > @@ -2852,6 +2852,27 @@ static int em_das(struct x86_emulate_ctxt *ctxt) > return X86EMUL_CONTINUE; > } > > +static int em_aad(struct x86_emulate_ctxt *ctxt) > +{ > + u8 al = ctxt->dst.val & 0xff; > + u8 ah = (ctxt->dst.val >> 8) & 0xff; > + > + al = (al + (ah * ctxt->src.val)) & 0xff; > + > + ctxt->dst.val = (ctxt->dst.val & 0xffff0000) | al; > + > + ctxt->eflags &= ~(X86_EFLAGS_PF | X86_EFLAGS_SF | X86_EFLAGS_ZF); > + > + if (!al) > + ctxt->eflags |= X86_EFLAGS_ZF; > + if (!(al & 1)) > + ctxt->eflags |= X86_EFLAGS_PF; This is wrong, it should check the parity of al (even=1, odd=0). Perhaps you can use the trick of em_das: /* Set PF, ZF, SF */ ctxt->src.type = OP_IMM; ctxt->src.val = 0; ctxt->src.bytes = 1; emulate_2op_SrcV(ctxt, "or"); Paolo > + if (al & 0x80) > + ctxt->eflags |= X86_EFLAGS_SF; > + > + return X86EMUL_CONTINUE; > +} > + > static int em_call(struct x86_emulate_ctxt *ctxt) > { > long rel = ctxt->src.val; > @@ -3801,7 +3822,7 @@ static const struct opcode opcode_table[256] = { > D(ImplicitOps | No64), II(ImplicitOps, em_iret, iret), > /* 0xD0 - 0xD7 */ > D2bv(DstMem | SrcOne | ModRM), D2bv(DstMem | ModRM), > - N, N, N, N, > + N, I(DstAcc | SrcImmByte | No64, em_aad), N, N, > /* 0xD8 - 0xDF */ > N, N, N, N, N, N, N, N, > /* 0xE0 - 0xE7 */ > -- > Gleb. > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >