From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753986Ab0JTQDo (ORCPT ); Wed, 20 Oct 2010 12:03:44 -0400 Received: from mail-yw0-f46.google.com ([209.85.213.46]:65034 "EHLO mail-yw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753905Ab0JTQDn (ORCPT ); Wed, 20 Oct 2010 12:03:43 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:x-enigmail-version:content-type :content-transfer-encoding; b=TxsMdBRgDI5yZ4T/1qQzzvkZQ7mLlDWIGB6qghsIUiA3ruD/ixwSPtNwYUxC1eQsW1 3eRdWPYA3WjOvjvkPH2i1vGfifBC/qzeLfcgY/A9cm0Vo+I5X7OJ9bmQSnm3AY31NV/i eV2DRT88NnK1pcv0QZwwf+NFxjMT/7/XjtQmc= Message-ID: <4CBF12D4.4070207@gmail.com> Date: Wed, 20 Oct 2010 18:03:32 +0200 From: Jiri Slaby User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; cs-CZ; rv:1.9.2.11) Gecko/20101013 SUSE/3.1.5 Thunderbird/3.1.5 MIME-Version: 1.0 To: Frederic Weisbecker CC: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, mm-commits@vger.kernel.org, Peter Zijlstra , Ingo Molnar Subject: Re: ptrace BUG [was: mmotm 2010-10-13-17-13 uploaded] References: <201010140044.o9E0iuR3029069@imap1.linux-foundation.org> <4CBF0FB7.3000602@gmail.com> <20101020155406.GC5387@nowhere> In-Reply-To: <20101020155406.GC5387@nowhere> X-Enigmail-Version: 1.1.2 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 10/20/2010 05:54 PM, Frederic Weisbecker wrote: > On Wed, Oct 20, 2010 at 05:50:15PM +0200, Jiri Slaby wrote: >> On 10/14/2010 02:13 AM, akpm@linux-foundation.org wrote: >>> The mm-of-the-moment snapshot 2010-10-13-17-13 has been uploaded to >> >> Hi, I tried to run a process in gdb and got this BUG: >> >> BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 >> IP: [] fetch_bp_busy_slots.clone.1+0x28/0x1c0 >> PGD 1bacfa067 PUD 13b7f1067 PMD 0 >> Oops: 0000 [#1] SMP >> last sysfs file: /sys/devices/virtual/net/tun0/statistics/collisions >> CPU 1 >> Modules linked in: dvb_usb_af9015 dvb_usb > > > > Do you have this fix? > > d580ff8699e8811a9af37e9de4dea375401bdeec > ("perf, hw_breakpoint: Fix crash in hw_breakpoint creation") > > It's in tip:/perf/core, which perhaps hasn't yet reached -next. > > > This should fix the problem. I applied the patch and got another BUG: WARNING: at /home/l/latest/xxx/kernel/fork.c:183 __put_task_struct+0xf2/0x110() Hardware name: To Be Filled By O.E.M. Modules linked in: dvb_usb_af9015 dvb_usb Pid: 4743, comm: gdb Not tainted 2.6.36-rc7-mm1_64+ #1295 Call Trace: [] warn_slowpath_common+0x7a/0xb0 [] warn_slowpath_null+0x15/0x20 [] __put_task_struct+0xf2/0x110 [] sys_ptrace+0x7f/0xc0 [] system_call_fastpath+0x16/0x1b ---[ end trace 4d39ff87d0cf3ac8 ]--- ------------[ cut here ]------------ WARNING: at /home/l/latest/xxx/kernel/fork.c:183 __put_task_struct+0xf2/0x110() Hardware name: To Be Filled By O.E.M. Modules linked in: dvb_usb_af9015 dvb_usb Pid: 4743, comm: gdb Tainted: G W 2.6.36-rc7-mm1_64+ #1295 Call Trace: [] warn_slowpath_common+0x7a/0xb0 [] warn_slowpath_null+0x15/0x20 [] __put_task_struct+0xf2/0x110 [] sys_ptrace+0x7f/0xc0 [] system_call_fastpath+0x16/0x1b ---[ end trace 4d39ff87d0cf3ac9 ]--- BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] exit_creds+0x1a/0x90 PGD 1abdc9067 PUD 1abdcb067 PMD 0 Oops: 0000 [#1] SMP last sysfs file: /sys/devices/virtual/net/tun0/statistics/collisions CPU 1 Modules linked in: dvb_usb_af9015 dvb_usb Pid: 4743, comm: gdb Tainted: G W 2.6.36-rc7-mm1_64+ #1295 To be filled by O.E.M./To Be Filled By O.E.M. RIP: 0010:[] [] exit_creds+0x1a/0x90 RSP: 0018:ffff8801a98e5f08 EFLAGS: 00010292 RAX: 0000000000000000 RBX: ffff88019584f500 RCX: 000000000003ffff RDX: ffffffff81812968 RSI: 0000000000000046 RDI: 0000000000000000 RBP: ffff8801a98e5f18 R08: 0000000000000034 R09: 000000000000e1fd R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000006 R13: 0000000000000368 R14: 0000000000000000 R15: 000000000003057f FS: 00007f4d44bb5700(0000) GS:ffff8800af280000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000001abff4000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process gdb (pid: 4743, threadinfo ffff8801a98e4000, task ffff88019583a080) Stack: ffff8801a98e5f18 ffff88019584f500 ffff8801a98e5f38 ffffffff810671ed ffff88019584f500 0000000000000006 ffff8801a98e5f78 ffffffff81074c4f 0000000000000003 fffffffffffffffd 00007f4d44bb56a8 0000000000000003 Call Trace: [] __put_task_struct+0x3d/0x110 [] sys_ptrace+0x7f/0xc0 [] system_call_fastpath+0x16/0x1b Code: 84 36 ff ff ff e9 0f ff ff ff 0f 0b 0f 0b 0f 1f 00 55 48 89 e5 53 48 89 fb 48 83 ec 08 48 8b 87 08 03 00 00 48 8b bf 00 03 00 00 <8b> 00 48 c7 83 00 03 00 00 00 00 00 00 f0 ff 0f 0f 94 c0 84 c0 RIP [] exit_creds+0x1a/0x90 RSP CR2: 0000000000000000 ---[ end trace 4d39ff87d0cf3aca ]--- psi[4748] trap int3 ip:7ffff3bdaa01 sp:7fffffffccc8 error:0 thanks, -- js