From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with SMTP id 2A8B06B0047 for ; Tue, 2 Mar 2010 14:59:04 -0500 (EST) From: "Rafael J. Wysocki" Subject: Re: unable to handle kernel paging request on resume with 2.6.33-00001-gbaac35c Date: Tue, 2 Mar 2010 21:01:21 +0100 References: <20100301175256.GA4034@tiehlicka.suse.cz> <20100302082543.GA4241@tiehlicka.suse.cz> <20100302154553.GB4241@tiehlicka.suse.cz> In-Reply-To: <20100302154553.GB4241@tiehlicka.suse.cz> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201003022101.21521.rjw@sisk.pl> Sender: owner-linux-mm@kvack.org To: Michal Hocko Cc: linux-kernel@vger.kernel.org, pm list , linux-mm@kvack.org List-ID: On Tuesday 02 March 2010, Michal Hocko wrote: > On Tue, Mar 02, 2010 at 09:25:43AM +0100, Michal Hocko wrote: > > On Tue, Mar 02, 2010 at 01:06:06AM +0100, Rafael J. Wysocki wrote: > > > On Monday 01 March 2010, Michal Hocko wrote: > > > > [Let's CC mm guys] > > > > > > I guess it's rather architecture-related than a genering mm issue. s/genering/generic/ (why did I write that?) ... > > > > Yes, it really looks strange. dup_mm+0x1c7 matches to: > > > > c102fc0e: 81 60 14 ff df ff ff andl $0xffffdfff,0x14(%eax) > > > > c102fc15: 8b 45 ec mov -0x14(%ebp),%eax > > > > c102fc18: c7 43 0c 00 00 00 00 movl $0x0,0xc(%ebx) > > > > c102fc1f: 89 03 mov %eax,(%ebx) > > > > c102fc21: 89 d8 mov %ebx,%eax > > > > c102fc23: e8 38 e6 06 00 call c109e260 > > > > c102fc28: 8b 43 48 mov 0x48(%ebx),%eax <<< BANG > > > > > > > > which corresponds to: > > > > kernel/fork.c:336 > > > > tmp->vm_flags &= ~VM_LOCKED; > > > > tmp->vm_mm = mm; > > > > tmp->vm_next = NULL; > > > > anon_vma_link(tmp); > > > > file = tmp->vm_file; <<< BANG > > > > > > > > ebx is tmp which somehow got deallocated. I cannot see how this could happened. > > > > > > Through a page tables corruption or a TLB issue, for example. > > > > I thought so. Is there any other possibility? Like a race with vma > > unlinking? I don't think that particular instruction would trigger the NULL poiter dereference in that case. In theory, it may be a result of a stack corruption if EBX was saved on the stack by anon_vma_link(). I'm not sure if that happens, though. > It really looks like some memory corruption. Now I got the following: > > BUG: unable to handle kernel NULL pointer dereference at (null) > IP: [] strcmp+0xe/0x22 > *pde = 00000000 > Oops: 0000 [#1] PREEMPT SMP > last sysfs file: /sys/devices/pci0000:00/0000:00:1e.0/0000:08:03.4/fw-host0/00000e1003d248c6/uevent > Modules linked in: fbcon font bitblit softcursor i915 drm_kms_helper drm fb i2c_algo_bit cfbcopyarea i2c > on snd_hda_codec_realtek arc4 ecb snd_hda_intel snd_hda_codec snd_pcm_oss snd_mixer_oss snd_pcm iwl3945 > d_timer snd_seq_device mac80211 snd fujitsu_laptop rtc_cmos cfg80211 rtc_core rtc_lib led_class snd_page > i_wait_scan] > > Pid: 16719, comm: udev-acl.ck Not tainted 2.6.33-00001-gbaac35c #11 FJNB1B5/LIFEBOOK S7110 > EIP: 0060:[] EFLAGS: 00010286 CPU: 0 > EIP is at strcmp+0xe/0x22 > EAX: 00000000 EBX: f71c0600 ECX: f70d0f00 EDX: f5a1d49c > ESI: 00000000 EDI: f5a1d49c EBP: f70d0dec ESP: f70d0de4 > DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 > Process udev-acl.ck (pid: 16719, ti=f70d0000 task=f6a65710 task.ti=f70d0000) > Stack: > f5a1d49c fffffffe f70d0dfc c01ea0c0 f5a1d440 f71c05a0 f70d0e14 c01ea267 > <0> f5a1d330 c044cfac f70d0f00 f6f44968 f70d0e3c c01b3a14 f70fcc80 f70d0e7c > <0> f6f449e0 f5a1d330 f5a1d440 f70d0f00 f6f44968 087bed70 f70d0e90 c01b508a > Call Trace: > [] ? sysfs_find_dirent+0x1b/0x2c > [] ? sysfs_lookup+0x2f/0xa6 > [] ? do_lookup+0xca/0x174 > [] ? link_path_walk+0x691/0xa22 > [] ? mntput_no_expire+0x1e/0xb2 > [] ? path_walk+0x3f/0x89 > [] ? path_init+0x73/0x114 > [] ? do_path_lookup+0x26/0x47 > [] ? do_filp_open+0xdc/0x79e > [] ? free_hot_page+0x55/0x59 > [] ? sysfs_put_link+0x0/0x1f > [] ? free_pages+0x22/0x24 > [] ? generic_readlink+0x69/0x73 > [] ? add_preempt_count+0x8/0x75 > [] ? sub_preempt_count+0x8/0x74 > [] ? _raw_spin_unlock+0x14/0x28 > [] ? do_sys_open+0x4d/0xe9 > [] ? filp_close+0x56/0x60 > [] ? sys_open+0x23/0x2b > [] ? sysenter_do_call+0x12/0x26 > Code: 31 c0 83 c9 ff f2 ae 4f 89 d1 49 78 06 ac aa 84 c0 75 f7 31 c0 aa 89 d8 5b 5e 5f 5d c3 55 89 e5 57 56 0f 1f 44 00 00 89 c6 89 d7 ae 75 08 84 c0 75 f8 31 c0 eb 04 19 c0 0c 01 5e 5f 5d c3 55 > EIP: [] strcmp+0xe/0x22 SS:ESP 0068:f70d0de4 > CR2: 0000000000000000 > ---[ end trace 877af85bb64785ae ]--- The question is whether hibernation is the reason of this or it's only a messenger. > > > > > What's the HEAD commit in this kernel tree? > > > > > > > > $ git describe > > > > v2.6.33-1-gbaac35c > > > > > > I can't find gbaac35c anywhere post 2.6.33. > > > > you should look at baac35c. Git describe displays gHASH Ah. > > > Can you just send the output > > > of "git show | head -1", please? > > > > The whole commit ID is baac35c4155a8aa826c70acee6553368ca5243a2 So this is just plain 2.6.33 plus one commit. Hmm. There are only a few changes directly related to hibernation in that kernel and none of them can possibly introduce a problem like that. Do you use s2disk or the in-kernel thing? Rafael -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org