Re: Sometimes the disk is unplugged and the umount operation enters the D state.

[Su Hua <suhua.tanke@gmail.com>]

Yeah, thank you, I found this patch yesterday, ：） I will backport it,
Happy New Year's Day.

suhua

> Best regards


Brian Foster <bfoster@redhat.com> 于2019年1月3日周四 上午12:12写道：
>
> On Thu, Dec 27, 2018 at 12:20:42PM +0800, Su Hua wrote:
> > Hi Brian：
> >
> > We use kernel version: 4.4.163
> >
> > Our test department found that this version of the kernel still has the
> > problem that the umount operation will enter the D state after the disk is
> > unplugged. The information is as follows:
> >
> > [Mon Dec 17 13:41:17 2018] INFO: task umount:19009 blocked for more than
> > 120 seconds.
> > [Mon Dec 17 13:41:17 2018]       Tainted: G        W  O    4.4.163 #4
> > [Mon Dec 17 13:41:17 2018] "echo 0 >
> > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> > [Mon Dec 17 13:41:17 2018] umount          D ffffffc000084974     0 19009
> >  8925 0x00000008
> > [Mon Dec 17 13:41:17 2018] Call trace:
> > [Mon Dec 17 13:41:17 2018] [<ffffffc000084974>] __switch_to+0x60/0x6c
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0007ed9d8>] __schedule+0x1a4/0x564
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0007eddd0>] schedule+0x38/0x90
> > [Mon Dec 17 13:41:17 2018] [<ffffffc00035a10c>]
> > xfs_ail_push_all_sync+0xac/0xf8
> > [Mon Dec 17 13:41:17 2018] [<ffffffc000343bd4>] xfs_unmountfs+0x48/0x110
> > [Mon Dec 17 13:41:17 2018] [<ffffffc000346db4>] xfs_fs_put_super+0x30/0x84
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0001896e0>]
> > generic_shutdown_super+0x68/0xdc
> > [Mon Dec 17 13:41:17 2018] [<ffffffc000189a34>] kill_block_super+0x1c/0x5c
> > [Mon Dec 17 13:41:17 2018] [<ffffffc000189bb0>]
> > deactivate_locked_super+0x5c/0x88
> > [Mon Dec 17 13:41:17 2018] [<ffffffc00018a948>] deactivate_super+0xa8/0xb4
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0001a4614>] cleanup_mnt+0x3c/0x74
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0001a46b0>] __cleanup_mnt+0x10/0x18
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0000b3f90>] task_work_run+0xa8/0xc4
> > [Mon Dec 17 13:41:17 2018] [<ffffffc000086458>] do_notify_resume+0x6c/0x74
> > [Mon Dec 17 13:41:17 2018] [<ffffffc0000839e0>] work_pending+0x1c/0x20
> >
> > And the trace info like this:
> > xfs_umount_D.txt
> > <https://github.com/zlsh007/Ohters/blob/master/Bug/xfs_umount_D.txt>
> >
> > Can you give me some advice, how can I solve this problem?
> >
>
> I'd probably start with commit e6b3bb78962e6 ("xfs: add "fail at
> unmount" error handling configuration") which went into v4.7. That may
> or may not depend on earlier error configuration work as well.
>
> Brian
>
> > Best regards