From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934039AbaEGPwx (ORCPT ); Wed, 7 May 2014 11:52:53 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:32534 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933440AbaEGPwu (ORCPT ); Wed, 7 May 2014 11:52:50 -0400 Message-ID: <536A56C3.2070505@oracle.com> Date: Wed, 07 May 2014 11:52:35 -0400 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Steven Rostedt , Oleg Nesterov CC: roland@redhat.com, LKML , Dave Jones Subject: Re: ptrace: gpf in syscall_trace_enter References: <53698021.5020108@oracle.com> <53699F7C.1040308@oracle.com> <20140507140422.GB17419@redhat.com> <20140507114938.28e300c6@gandalf.local.home> In-Reply-To: <20140507114938.28e300c6@gandalf.local.home> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/07/2014 11:49 AM, Steven Rostedt wrote: > On Wed, 7 May 2014 16:04:22 +0200 > Oleg Nesterov wrote: > >> On 05/06, Sasha Levin wrote: >>> >>> On 05/06/2014 08:36 PM, Sasha Levin wrote: >>>> Hi all, >>>> >>>> While fuzzing with trinity inside a KVM tools guest running the latest -next >>>> kernel I've stumbled on the following spew: >>> >>> And another similar trace: >> >> Again, this looks like __DO_TRACE() trying to call it_func_ptr->func(). >> >>> [ 6897.628729] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC >>> [ 6897.629654] Dumping ftrace buffer: >>> [ 6897.630034] (ftrace buffer empty) >>> [ 6897.630034] Modules linked in: >>> [ 6897.630034] CPU: 24 PID: 23736 Comm: trinity-c148 Tainted: G B 3.15.0-rc4-next-20140506-sasha-00021-gc164334-dirty #447 >>> [ 6897.630034] task: ffff88002a870000 ti: ffff88000ef04000 task.ti: ffff88000ef04000 >>> [ 6897.630034] RIP: syscall_trace_leave (include/trace/events/syscalls.h:42 arch/x86/kernel/ptrace.c:1517) > > Thanks for sending the objdump, but then I just realized that this dump > doesn't have the actual RIP. It just says syscall_trace_leave, without > even giving me the offset. > > As the objdump is just of the object files and not the vmlinux, I would > need the offset from syscall_trace_leave of the RIP. 2803: 41 ff 14 24 callq *(%r12) <=== Here 2807: 49 83 c4 10 add $0x10,%r12 280b: 49 83 3c 24 00 cmpq $0x0,(%r12) Thanks, Sasha