From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966315AbXDGUT3 (ORCPT ); Sat, 7 Apr 2007 16:19:29 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S966328AbXDGUT3 (ORCPT ); Sat, 7 Apr 2007 16:19:29 -0400 Received: from nz-out-0506.google.com ([64.233.162.230]:48894 "EHLO nz-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966315AbXDGUT2 (ORCPT ); Sat, 7 Apr 2007 16:19:28 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=JbVuQU2iwNgVqX0DDnkXLoWSXdo6yZgi5l7usbjXpqZm85giV2NODL9/0pc2UBW/GB7W4A5X52M4eJfDStO0hKqyJwdB4d2srPtIP9/cI3GNl5rEa6B75lyBr/sd5TE5YZDUZ7UKRhtjLDD1uUyRQiS/SGFI6AS/VZ493R4f7ZA= Message-ID: <6bffcb0e0704071319u373cc6fci2e0637c57ee5381e@mail.gmail.com> Date: Sat, 7 Apr 2007 22:19:27 +0200 From: "Michal Piotrowski" To: "Andrew Morton" Subject: Re: mm snapshot broken-out-2007-04-07-03-27.tar.gz uploaded Cc: LKML , "Roland McGrath" In-Reply-To: <20070407131351.39c7884d.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <200704071029.l37ATdKR032505@shell0.pdx.osdl.net> <46178ECC.2030107@googlemail.com> <20070407105328.836902d1.akpm@linux-foundation.org> <4617DE67.4090801@googlemail.com> <20070407113829.c10e9fd1.akpm@linux-foundation.org> <6bffcb0e0704071148m238a7d96x5038e1c9f4fdfeeb@mail.gmail.com> <20070407131351.39c7884d.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 07/04/07, Andrew Morton wrote: > On Sat, 7 Apr 2007 20:48:43 +0200 "Michal Piotrowski" wrote: > > > On 07/04/07, Andrew Morton wrote: > > > On Sat, 07 Apr 2007 20:09:43 +0200 Michal Piotrowski wrote: > > > > > > > BTW. I guess that this need a similar fix. > > > > > > > > kernel BUG at kernel/ptrace.c:494! > > > > invalid opcode: 0000 [#2] > > > > PREEMPT SMP > > > > last sysfs file: devices/platform/w83627hf.656/temp2_input > > > > Modules linked in: ipt_MASQUERADE iptable_nat nf_nat nfsd exportfs lockd nfs_acl autofs4 sunrpc af_packet nf_conntrack_netbios_ns ipt_REJECT nf_conntrack_ipv4 xt_state nf_conntrack nfnetlink iptable_filter ip_tables ip6t_REJECT xt_tcpudp ip6table_filter ip6_tables x_tables ipv6 binfmt_misc thermal processor fan container nvram snd_intel8x0 snd_ac97_codec ac97_bus snd_seq_dummy snd_seq_oss snd_seq_midi_event snd_seq snd_seq_device snd_pcm_oss snd_mixer_oss intel_agp snd_pcm agpgart evdev snd_timer snd soundcore i2c_i801 snd_page_alloc ide_cd cdrom rtc unix > > > > CPU: 1 > > > > EIP: 0060:[] Not tainted VLI > > > > EFLAGS: 00010202 (2.6.21-rc6-mm1 #1) > > > > EIP is at ptrace_exit+0x29/0x21d > > > > > > > > > > no, I don't see what would cause that. Was there no call trace? > > > > Here is a call trace (it was in the first email). > > > > Call Trace: > > [] do_exit+0x16b/0x86c > > [] die+0x206/0x22c > > [] do_trap+0x8a/0xa4 > > [] do_invalid_op+0x88/0x92 > > [] error_code+0x79/0x80 > > [] ptrace_do_wait+0x1eb/0x510 > > [] do_wait+0x9d6/0xbad > > [] sys_wait4+0x30/0x32 > > [] sys_waitpid+0x27/0x29 > > [] syscall_call+0x7/0xb > > [] 0xb7f36410 > > Was that with the earlier ptrace fix applied? No, it wasn't. I'll retest with patch applied. > > Because what could happen is that ptrace_do_wait() (or anything else) > goes BUG, then the trap handler ends up calling do_exit(), which calls > ptrace_exit() which will then go BUG again over non-zero preempt_count. > > Asserting that preempt_count==0 on the do_exit() path is a bad idea, because > do_exit() is called on the oops path - we're virtually assured that we'll get > recursive crashes. > > I think I'll just disable the whole NO_LOCKS thing. > Regards, Michal -- Michal K. K. Piotrowski LTG - Linux Testers Group (PL) (http://www.stardust.webpages.pl/ltg/) LTG - Linux Testers Group (EN) (http://www.stardust.webpages.pl/linux_testers_group_en/)