From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 65561] KVM:Entry failed on Single stepping sti instruction Date: Sat, 24 May 2014 05:56:12 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit To: kvm@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.19.201]:33614 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750839AbaEXF4P (ORCPT ); Sat, 24 May 2014 01:56:15 -0400 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 9AF5620386 for ; Sat, 24 May 2014 05:56:14 +0000 (UTC) Received: from bugzilla2.web.kernel.org (bugzilla2.web.kernel.org [172.20.200.52]) by mail.kernel.org (Postfix) with ESMTP id 1420F20165 for ; Sat, 24 May 2014 05:56:13 +0000 (UTC) In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: https://bugzilla.kernel.org/show_bug.cgi?id=65561 --- Comment #24 from Jatin Kumar --- > linux:~/code/cvedr # ./accessmsr > Segmentation fault You got a seg fault because it is privileged instruction and I run it in kernel mode not user mode. But you are likely to be running your program in user mode. Try something like out instruction. > Even though my c program in the guest os got a segmentation fault, from the > host os level, I don't see the printk statement is triggered, so this is not > about privileged instructions or unprivileged instructions. I think there > must be some other conditions to trigger these printk statements. After getting the VM_EXIT it must be first checking if it requires to emulate or should generate a fault. In this case it would have generated the fault without emulating it. Again, you can try it with 'out' instruction. -- You are receiving this mail because: You are watching the assignee of the bug.