Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753134AbaBXRna (ORCPT ); Mon, 24 Feb 2014 12:43:30 -0500 Received: from terminus.zytor.com ([198.137.202.10]:39122 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752376AbaBXRn3 (ORCPT ); Mon, 24 Feb 2014 12:43:29 -0500 Message-ID: <530B8492.2050403@zytor.com> Date: Mon, 24 Feb 2014 09:42:42 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: Vince Weaver CC: Peter Zijlstra , Linux Kernel , Ingo Molnar , "H.J. Lu" , Steven Rostedt Subject: Re: perf_fuzzer compiled for x32 causes reboot References: <53084317.4090304@zytor.com> <530AD71E.50800@zytor.com> <18f0cea3-7e3b-4477-b433-0269f3de976b@email.android.com> <20140224172536.GD9987@twins.programming.kicks-ass.net> In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/24/2014 09:41 AM, Vince Weaver wrote: > On Mon, 24 Feb 2014, Vince Weaver wrote: > >> I do note that >> perf_callchain_user(); >> >> Does >> fp = (void __user *)regs->bp; >> >> ... >> >> bytes = copy_from_user_nmi(&frame, fp, sizeof(frame)); >> >> >> And in my particular executable RBP has nothing to do with a frame >> pointer, but is instead being used as a general purpose register. > > and as a reminder, I'm seeing this on an x32 executable, so > perf_callchain_user32() is probably coming into play. > > So maybe it is an x32 issue after all. > No. if (!test_thread_flag(TIF_IA32)) return 0; TIF_IA32 is clear for an x32 process. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/