lkml.org 
[lkml]   [2012]   [Sep]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH next/mmotm] ext4: fix cache_es after merge_left
On Thu, Sep 27, 2012 at 04:39:20PM -0400, Theodore Ts'o wrote:
> On Thu, Sep 27, 2012 at 01:31:28PM -0700, Hugh Dickins wrote:
> > Kernel build with CONFIG_DEBUG_SLAB or CONFIG_SLUB_DEBUG slub_debug=FPZ
> > gives me kernel BUG at fs/ext4/extents_status.c:142! That's the
> > BUG_ON(es->start + es->len < es->start) in extent_status_end() called
> > from ext4_es_insert_extent(). tree->cache_es has been freed and poisoned.
> >
> > This comes from when ext4_es_try_to_merge_left() merges es into leftward
> > es1, but ext4_es_insert_extent()'s out then updates cache_es to the freed
> > extent_status. ext4_es_try_to_merge_right() does not pose a problem.
> >
> > Change ext4_es_try_to_merge_left() to return whichever extent_status
> > should be recorded in tree->cache_es. Remove cache_es update from
> > both of them, leaving that to ext4_es_insert_extent()'s out label.
> >
> > Signed-off-by: Hugh Dickins <hughd@google.com>
>
> Hugh, thanks for finding this bug!
>
> Zheng, you were going to send me an updated patch series; can you take
> care of merging this patch into your patch series (and crediting Hugh
> with a Signed-off-by as appropriate)?

Yeah, thanks for fixing it, although I have fixed this problem in my new
patch set. I will add a Signed-off-by into the patch.

Regards,
Zheng


\
 
 \ /
  Last update: 2012-09-28 01:21    [W:0.077 / U:0.272 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site