On Fri, Dec 14, 2012 at 11:44:22AM +0100, Paolo Bonzini wrote: > 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 <gleb@xxxxxxxxxx> > > 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). > Oops, yes it should check number of bits set, not value itself. > 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"); Will do. > > 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@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- Gleb. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
