Re: [GIT PULL] btrfs fixes and cleanups

[Liu Bo <bo.li.liu@oracle.com>]

Hi,

On Wed, Dec 28, 2016 at 05:30:59PM +0800, Qu Wenruo wrote:
> Hi Liu,
> 
> At 12/15/2016 03:13 PM, Liu Bo wrote:
> > Hi David,
> > 
> > This is the collection of my patches targetting 4.10, I've
> > dropped patch "Btrfs: adjust len of writes if following a
> > preallocated extent" because of the deadlock caused by this
> > commit.
> > 
> > Patches are based on v4.9-rc8, and test against fstests with
> > default mount options has been taken to make sure it doesn't
> > break anything.
> > 
> > I haven't got a kernel.org git repo, so this is mainly for
> > tracking purpose and for testing git flow.
> > 
> > (cherry-pick patches might be the only way at this moment...sorry
> > for the inconvenience.)
> > 
> > Anyway, patches can be found at
> > 
> > 	https://github.com/liubogithub/btrfs-work.git for-dave
> > 
> > Thanks,
> > liubo
> > 
> > Liu Bo (9):
> >   Btrfs: add 'inode' for extent map tracepoint
> >   Btrfs: add truncated_len for ordered extent tracepoints
> >   Btrfs: use down_read_nested to make lockdep silent
> >   Btrfs: fix lockdep warning about log_mutex
> >   Btrfs: fix truncate down when no_holes feature is enabled
> >   Btrfs: fix btrfs_ordered_update_i_size to update disk_i_size properly
> >   Btrfs: fix comment in btrfs_page_mkwrite
> >   Btrfs: clean up btrfs_ordered_update_i_size
> 
> While testing David's for-next-20161219 branch, I found btrfs/06[0-5] will
> cause the following kernel panic when ran them in a row.
> 
> [ 4207.963063] assertion failed: disk_i_size < i_size, file:
> fs/btrfs//ordered-data.c, line: 1041
> [ 4207.963722] ------------[ cut here ]------------
> [ 4207.964008] kernel BUG at fs/btrfs//ctree.h:3418!
> [ 4207.964008] invalid opcode: 0000 [#1] SMP
> [ 4207.964008] Modules linked in: btrfs(O) netconsole ext4 jbd2 mbcache xor
> zlib_deflate raid6_pq xfs [last unloaded: btrfs]
> [ 4207.964008] CPU: 0 PID: 3829 Comm: kworker/u4:5 Tainted: G O    4.9.0+
> #60
> [ 4207.964008] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
> 1.10.1-20161122_114906-anatol 04/01/2014
> [ 4207.964008] Workqueue: btrfs-endio-write btrfs_endio_write_helper [btrfs]
> [ 4207.964008] task: ffff88000bbf8040 task.stack: ffffc90006598000
> [ 4207.964008] RIP: 0010:[<ffffffffa0462245>]  [<ffffffffa0462245>]
> assfail.constprop.10+0x1c/0x1e [btrfs]
> <snip>
> [ 4207.964008] Call Trace:
> [ 4207.964008]  [<ffffffffa03f1f41>] btrfs_ordered_update_i_size+0x2b1/0x2e0
> [btrfs]
> [ 4207.964008]  [<ffffffffa03dd435>] btrfs_finish_ordered_io+0x335/0x6b0
> [btrfs]
> [ 4207.964008]  [<ffffffffa03dd7c5>] finish_ordered_fn+0x15/0x20 [btrfs]
> [ 4207.964008]  [<ffffffffa040961f>] btrfs_scrubparity_helper+0xef/0x610
> [btrfs]
> [ 4207.964008]  [<ffffffffa0409bce>] btrfs_endio_write_helper+0xe/0x10
> [btrfs]
> [ 4207.964008]  [<ffffffff810ec9ef>] process_one_work+0x2af/0x720
> [ 4207.964008]  [<ffffffff810ec96b>] ? process_one_work+0x22b/0x720
> [ 4207.964008]  [<ffffffff810eceab>] worker_thread+0x4b/0x4f0
> [ 4207.964008]  [<ffffffff810ece60>] ? process_one_work+0x720/0x720
> [ 4207.964008]  [<ffffffff810ece60>] ? process_one_work+0x720/0x720
> [ 4207.964008]  [<ffffffff810f3d93>] kthread+0xf3/0x110
> [ 4207.964008]  [<ffffffff810f3ca0>] ? kthread_park+0x60/0x60
> [ 4207.964008]  [<ffffffff818af7c7>] ret_from_fork+0x27/0x40
> [ 4207.964008] Code: c7 00 e4 46 a0 48 89 e5 e8 c8 3c d8 e0 0f 0b 55 89 f1
> 48 c7 c2 83 90 46 a0 48 89 fe 48 c7 c7 b0 e4 46 a0 48 89 e5 e8 aa 3c d8 e0
> <0f> 0b 55 89 f1 48 c7 c2 fb 90 46 a0 48 89 fe 48 c7 c7 e8 e5 46
> [ 4207.964008] RIP  [<ffffffffa0462245>] assfail.constprop.10+0x1c/0x1e
> [btrfs]
> [ 4207.964008]  RSP <ffffc9000659bc18>
> [ 4207.964008] ---[ end trace f7759d2fce14da9f ]---
> 
> Not sure if it's related to patch or just it exposed some bug we don't find
> before.
> 
> Hopes it will help.
>

Thanks for spotting it, just found out that this ASSERT is not true any
more after patch "Btrfs: fix btrfs_ordered_update_i_size to update
disk_i_size properly".

I'm doing a v2 to remove it.

Thanks,

-liubo
 
> Thanks,
> Qu
> 
> >   Btrfs: fix another race between truncate and lockless dio write
> > 
> >  fs/btrfs/extent-tree.c       |  3 ++-
> >  fs/btrfs/inode.c             | 43 +++++++++++++++++++++++++++++++++++--------
> >  fs/btrfs/ordered-data.c      | 42 ++++++++++++++++++++++++------------------
> >  fs/btrfs/tree-log.c          | 13 ++++++++++---
> >  include/trace/events/btrfs.h | 16 ++++++++++++----
> >  5 files changed, 83 insertions(+), 34 deletions(-)
> > 
> 
>