From d44e1212230a68f9dccd1a95b5c8ca5217c62094 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 9 Feb 2015 10:02:05 +0100 Subject: [PATCH] KVM: x86: emulate: correct page fault error code for NoWrite instructions 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 Signed-off-by: Paolo Bonzini --- 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 81dcf79..a943bf0 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; -- 2.7.4