[PATCH] KVM: x86: emulate: correct page fault error code for NoWrite instructions
From: Paolo Bonzini
Date: Mon Feb 09 2015 - 04:03:48 EST
NoWrite instructions (e.g. cmp or test) never set the "write access"
bit in the error code, even if one of the operands is treated as a
destination.
Fixes: c205fb7d7d4f81e46fc577b707ceb9e356af1456
Cc: Nadav Amit <namit@xxxxxxxxxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
arch/x86/kvm/emulate.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 81dcf7964701..a943bf0c06d0 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -4954,7 +4954,8 @@ int x86_emulate_insn(struct x86_emulate_ctxt *ctxt)
rc = segmented_read(ctxt, ctxt->dst.addr.mem,
&ctxt->dst.val, ctxt->dst.bytes);
if (rc != X86EMUL_CONTINUE) {
- if (rc == X86EMUL_PROPAGATE_FAULT &&
+ if (!(ctxt->d & NoWrite) &&
+ rc == X86EMUL_PROPAGATE_FAULT &&
ctxt->exception.vector == PF_VECTOR)
ctxt->exception.error_code |= PFERR_WRITE_MASK;
goto done;
--
1.8.3.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/