On Mon, Oct 31, 2016 at 08:54:33PM +0100, Stefan Wahren wrote:

[  366.696043] INFO: task ext4lazyinit:70 blocked for more than 120 seconds.
[  366.703046]       Not tainted 4.9.0-rc1 #7
[  366.707188] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
[  366.715161] ext4lazyinit    D c05aa6ac     0    70      2 0x00000000

This looks like a very different problem - I guess one for ext4 people.

[  366.721713] [<c05aa6ac>] (__schedule) from [<c05aafb8>] (schedule+0x3c/0xbc)
[  366.728972] [<c05aafb8>] (schedule) from [<c05aee38>]
(schedule_timeout+0x23c/0x3d8)
[  366.736917] [<c05aee38>] (schedule_timeout) from [<c05aa398>]
(io_schedule_timeout+0xb8/0x13c)
[  366.745721] [<c05aa398>] (io_schedule_timeout) from [<c05ab9d8>]
(T.1434+0xac/0x12c)
[  366.753671] [<c05ab9d8>] (T.1434) from [<c02c7668>]
(submit_bio_wait+0x50/0x68)
[  366.761078] [<c02c7668>] (submit_bio_wait) from [<c02d9a58>]
(blkdev_issue_zeroout+0x174/0x1ec)
[  366.769984] [<c02d9a58>] (blkdev_issue_zeroout) from [<c0196e4c>]
(ext4_init_inode_table+0x1ac/0x3b0)
[  366.779410] [<c0196e4c>] (ext4_init_inode_table) from [<c01ba770>]
(ext4_lazyinit_thread+0x280/0x398)
[  366.788803] [<c01ba770>] (ext4_lazyinit_thread) from [<c003bce4>]
(kthread+0xc4/0xe0)
[  366.796828] [<c003bce4>] (kthread) from [<c000a34c>]
(ret_from_fork+0x14/0x28)
[  366.804200]
[  366.804200] Showing all locks held in the system:
[  366.810465] 2 locks held by khungtaskd/10:
[  366.814707]  #0: [  366.816500]  (
rcu_read_lock[  366.819360] ){......}
, at: [  366.822236] [<c0093a10>] watchdog+0xb4/0x61c
[  366.826656]  #1: [  366.828450]  (
tasklist_lock[  366.831312] ){.+.+..}
, at: [  366.834320] [<c0051dbc>] debug_show_all_locks+0x28/0x1bc
[  366.839701] 4 locks held by ext4lazyinit/70:
[  366.844107]  #0: [  366.845897]  (
&type->s_umount_key[  366.849280] #22
){++++++}[  366.851866] , at:
[  366.854044] [<c01ba5c4>] ext4_lazyinit_thread+0xd4/0x398
[  366.859400]  #1: [  366.861178]  (
sb_writers[  366.863897] #3
){.+.+.+}[  366.866412] , at:
[  366.868475] [<c01ba5dc>] ext4_lazyinit_thread+0xec/0x398
[  366.873925]  #2: [  366.875716]  (
jbd2_handle[  366.878405] ){++++..}
, at: [  366.881292] [<c01f661c>] start_this_handle+0xec/0x404
[  366.886492]  #3: [  366.888284]  (
&meta_group_info[i]->alloc_sem[  366.892620] ){++++..}
, at: [  366.895624] [<c0196d58>] ext4_init_inode_table+0xb8/0x3b0
[  366.901093] 4 locks held by bash/385:
[  366.904895]  #0: [  366.906686]  (
sb_writers[  366.909288] #4
){.+.+.+}[  366.911787] , at:
[  366.913972] [<c011f7d4>] vfs_write+0x194/0x1a4
[  366.918456]  #1: [  366.920234]  (
&of->mutex[  366.922824] ){+.+.+.}
, at: [  366.925940] [<c019029c>] kernfs_fop_write+0xc0/0x1d0
[  366.930942]  #2: [  366.932714]  (
s_active[  366.935265] #43
){.+.+.+}[  366.937864] , at:
[  366.939927] [<c01902a4>] kernfs_fop_write+0xc8/0x1d0
[  366.945029]  #3: [  366.946818]  (
pm_mutex[  366.949242] ){+.+.+.}
, at: [  366.952111] [<c005b7e4>] pm_suspend+0x90/0x81c
[  366.956697]
[  366.958229] =============================================

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