KVM: x86: Do not push eflags.vm on pushf

anadav · bonzini · commit bc397a6c914c · 2014-12-10T12:51:28.000+01:00
The pushf instruction does not push eflags.VM, so emulation should not do so as
well.  Although eflags.RF should not be pushed as well, it is already cleared
by the time pushf is executed.

Signed-off-by: Nadav Amit &lt;namit@cs.technion.ac.il&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
@@ -1861,7 +1861,7 @@ static int em_pusha(struct x86_emulate_ctxt *ctxt)
 
 static int em_pushf(struct x86_emulate_ctxt *ctxt)
 {
-	ctxt->src.val =  (unsigned long)ctxt->eflags;
+	ctxt->src.val = (unsigned long)ctxt->eflags & ~EFLG_VM;
 	return em_push(ctxt);
 }
 

Original file line number	Diff line number	Diff line change
`@@ -1861,7 +1861,7 @@ static int em_pusha(struct x86_emulate_ctxt *ctxt)`
`1861`	`1861`
`1862`	`1862`	`static int em_pushf(struct x86_emulate_ctxt *ctxt)`
`1863`	`1863`	`{`
`1864`		`- ctxt->src.val = (unsigned long)ctxt->eflags;`
	`1864`	`+ ctxt->src.val = (unsigned long)ctxt->eflags & ~EFLG_VM;`
`1865`	`1865`	`return em_push(ctxt);`
`1866`	`1866`	`}`
`1867`	`1867`