lkml.org 
[lkml]   [2011]   [Aug]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: list corruption in the last few days. (block ? crypto ?)
From
On Mon, Aug 8, 2011 at 9:31 AM, Xiaotian Feng <xtfeng@gmail.com> wrote:
> On Mon, Aug 8, 2011 at 2:18 PM, Pekka Enberg <penberg@kernel.org> wrote:
>> On Mon, Aug 8, 2011 at 9:14 AM, Xiaotian Feng <xtfeng@gmail.com> wrote:
>>> On Mon, Aug 8, 2011 at 1:18 PM, Pekka Enberg <penberg@kernel.org> wrote:
>>>> Hi Linus,
>>>>
>>>> On Sun, Aug 7, 2011 at 11:58 AM, Pekka Enberg <penberg@kernel.org> wrote:
>>>>>>
>>>>>> Christoph, I've been reading the code and spotted two potential issues in
>>>>>> __slab_free(). The first one seems like an off-by-one where our
>>>>>> comparison
>>>>>> in deactivate_slab() doesn't match __slab_free.
>>>>>>
>>>>>> The other one is remove_full() call in __slab_free() that can get called
>>>>>> even if cache debugging is not enabled.
>>>>>>
>>>>>> Hmm?
>>>>
>>>> On Sun, 7 Aug 2011, Linus Torvalds wrote:
>>>>>
>>>>> I'd like to do -rc1 today, regardless of whether this fixes things or
>>>>> not (-rc1 is already a few days delayed).
>>>>>
>>>>> The patch seems to be a good fix, and a likely candidate for the
>>>>> corruption. Commit log and sign-off? I assume you've given it some
>>>>> testing, even if you couldn't reproduce the original issue?
>>>>
>>>> No, I haven't tested the patch myself but here's one in proper format in
>>>> case someone wants to test it.
>>>
>>> I applied it and I'm still seeing the corruption warning start from this :(
>>>
>>>  [ 3674.255030] ------------[ cut here ]------------
>>>  [ 3674.255040] WARNING: at lib/list_debug.c:53 __list_del_entry+0xa1/0xd0()
>>>  [ 3674.255042] Hardware name: 42424XC
>>>  [ 3674.255045] list_del corruption. prev->next should be
>>> ffffea0000493420, but was ffffea0001ab0520
>>>  [ 3674.255047] Modules linked in: ip6table_filter ip6_tables
>>> ipt_MASQUERADE iptable_nat nf_nat nf_conntrack_ipv4 nf_defrag_ipv4
>>> xt_state nf_conntrack ipt_REJECT xt_CHECKSUM iptable_mangle xt_tcpudp
>>> iptable_filter ip_tables x_tables binfmt_misc bridge stp parport_pc
>>> ppdev snd_hda_codec_conexant snd_hda_intel snd_hda_codec snd_hwdep
>>> snd_pcm thinkpad_acpi arc4 cryptd aes_x86_64 aes_generic snd_seq_midi
>>> i915 snd_rawmidi snd_seq_midi_event snd_seq joydev iwlagn btusb
>>> snd_timer snd_seq_device drm_kms_helper bluetooth uvcvideo snd
>>> videodev drm mac80211 cfg80211 i2c_algo_bit soundcore tpm_tis tpm
>>> tpm_bios lp snd_page_alloc psmouse serio_raw v4l2_compat_ioctl32 nvram
>>> video parport usbhid hid sdhci_pci firewire_ohci ahci libahci sdhci
>>> firewire_core crc_itu_t e1000e
>>>  [ 3674.255129] Pid: 3, comm: ksoftirqd/0 Not tainted 3.1.0-rc1+ #38
>>>  [ 3674.255131] Call Trace:
>>>  [ 3674.255138]  [<ffffffff8106db3f>] warn_slowpath_common+0x7f/0xc0
>>>  [ 3674.255143]  [<ffffffff8106dc36>] warn_slowpath_fmt+0x46/0x50
>>>  [ 3674.255147]  [<ffffffff81331851>] __list_del_entry+0xa1/0xd0
>>>  [ 3674.255151]  [<ffffffff81331891>] list_del+0x11/0x40
>>>  [ 3674.255156]  [<ffffffff81179631>] __slab_free+0x3d1/0x3e0
>>>  [ 3674.255162]  [<ffffffff811c5b06>] ? bvec_free_bs+0x26/0x40
>>>  [ 3674.255166]  [<ffffffff8117ab27>] ? kmem_cache_free+0x97/0x220
>>>  [ 3674.255170]  [<ffffffff811c5b06>] ? bvec_free_bs+0x26/0x40
>>>  [ 3674.255174]  [<ffffffff811c5b06>] ? bvec_free_bs+0x26/0x40
>>>  [ 3674.255179]  [<ffffffff8117ac9f>] kmem_cache_free+0x20f/0x220
>>
>> Can you please also run
>>
>>  addr2line -e vmlinux
>>  0xffffffff81179631
>>
>
> /opt/upstream/linux-3.0/mm/slub.c:1061
>
>
> /*
>  * list_lock must be held.
>  */
> static void remove_full(struct kmem_cache *s, struct page *page)
> {
>        if (!(s->flags & SLAB_STORE_USER))
>                return;
>
>        list_del(&page->lru);       <=== here
> }

OK, so it's the full list. Looking at deactivate_slab() we actually
can access the list without n->list_lock held. Does the attached patch
help?

Pekka
[unhandled content-type:application/octet-stream]
\
 
 \ /
  Last update: 2011-08-08 08:41    [W:0.071 / U:1.104 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site