x86 emulator: fix parity calculation for AAD instruction

PATCH In review Gleb Natapov 2 participants 2 messages Feb 13, 2013

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x86 KVM KVM x86

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Gleb Natapov

author

2013-02-13 15:50 UTC #0 lore raw

PATCH 1/1 x86 emulator: fix parity calculation for AAD instruction

Reported-by Paolo Bonzini <[email protected]>

Signed-off-by Gleb Natapov <[email protected]>

arch/x86/kvm/emulate.c +5 -8

index 2b11318..a335cc6 100644
@@ -2995,14 +2995,11 @@ static int em_aad(struct x86_emulate_ctxt *ctxt)
 
 	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;
+	/* Set PF, ZF, SF */
+	ctxt->src.type = OP_IMM;
+	ctxt->src.val = 0;
+	ctxt->src.bytes = 1;
+	fastop(ctxt, em_or);
 
 	return X86EMUL_CONTINUE;
 }

--
Gleb.

Paolo Bonzini

maintainer Reviewed-by on v1 1/1

2013-02-13 15:57 UTC #1 lore raw

Il 13/02/2013 16:50, Gleb Natapov ha scritto:

Quoted 29 lines

Reported-by Paolo Bonzini <[email protected]>

Signed-off-by Gleb Natapov <[email protected]>

arch/x86/kvm/emulate.c +5 -9

index 2b11318..a335cc6 100644
@@ -2995,14 +2995,11 @@ static int em_aad(struct x86_emulate_ctxt *ctxt)
 
 	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;
+	/* Set PF, ZF, SF */
+	ctxt->src.type = OP_IMM;
+	ctxt->src.val = 0;
+	ctxt->src.bytes = 1;
+	fastop(ctxt, em_or);
 
 	return X86EMUL_CONTINUE;
 }
--

Quoted 2 lines

Gleb.

Reviewed-by Paolo Bonzini <[email protected]>