From 7f662273e476e2d7ff44f411fa9f17c946480100 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Mon, 10 Dec 2012 11:42:30 +0200 Subject: KVM: emulator: implement AAD instruction Windows2000 uses it during boot. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=50921 Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) (limited to 'arch/x86/kvm/emulate.c') diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a27e7637110..47d62e16f9e 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; + 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 */ -- cgit v1.2.3-70-g09d2