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From: TomK <tk@mdevsys.com>
To: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: linux-scsi@vger.kernel.org,
	Himanshu Madhani <himanshu.madhani@qlogic.com>,
	Quinn Tran <quinn.tran@qlogic.com>,
	Giridhar Malavali <giridhar.malavali@qlogic.com>
Subject: Re: Kernel 4.8.4: INFO: task kworker/u16:8:289 blocked for more than 120 seconds.
Date: Tue, 25 Oct 2016 22:05:06 -0400	[thread overview]
Message-ID: <58bfd43f-ff17-f724-9adf-ffd1f828a0e9@mdevsys.com> (raw)
In-Reply-To: <b12c29d1-64a2-16dd-f38e-b4226e606df2@mdevsys.com>

On 10/25/2016 1:28 AM, TomK wrote:
> On 10/24/2016 2:36 AM, Nicholas A. Bellinger wrote:
>> Hi TomK,
>>
>> Thanks for reporting this bug.  Comments inline below.
>>
>> On Mon, 2016-10-24 at 00:45 -0400, TomK wrote:
>>> On 10/24/2016 12:32 AM, TomK wrote:
>>>> On 10/23/2016 10:03 PM, TomK wrote:
>>>>> Hey,
>>>>>
>>>>> Has anyone seen this and could have a workaround?  Seems like it is
>>>>> more
>>>>> Kernel related with various apps not just target apparently not but
>>>>> wondering if there is an interim solution
>>>>> (https://access.redhat.com/solutions/408833)
>>>>>
>>>>> Getting this message after few minutes of usage from the QLA2xxx
>>>>> driver.
>>>>>  This is after some activity on an ESXi server (15 VM's) that I'm
>>>>> connecting to this HBA.  I've tried the following tuning parameters
>>>>> but
>>>>> there was no change in behaviour:
>>>>>
>>>>> vm.dirty_background_ratio = 5
>>>>> vm.dirty_ratio = 10
>>>>>
>>>>> Details:
>>>>>
>>>>>
>>>>> Oct 23 21:28:25 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
>>>>> Oct 23 21:28:29 mbpc-pc kernel: ABORT_TASK: Found referenced qla2xxx
>>>>> task_tag: 1128612
>>>>> Oct 23 21:28:42 mbpc-pc kernel: ABORT_TASK: Sending
>>>>> TMR_FUNCTION_COMPLETE for ref_tag: 1128612
>>>>> Oct 23 21:28:42 mbpc-pc kernel: ABORT_TASK: Found referenced qla2xxx
>>>>> task_tag: 1129116
>>
>> You are likely hitting a known v4.1+ regression, not yet merged up to
>> v4.8.y code:
>>
>> https://github.com/torvalds/linux/commit/527268df31e57cf2b6d417198717c6d6afdb1e3e
>>
>>
>>>>> Jan  6 23:52:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
>>>>> successfully started
>>>>> Oct 23 21:30:18 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
>>>>> Jan  6 23:54:01 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
>>>>> successfully started
>>>>> Oct 23 21:32:16 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
>>>>> Oct 23 21:32:24 mbpc-pc kernel: INFO: task kworker/u16:8:289
>>>>> blocked for
>>>>> more than 120 seconds.
>>>>> Oct 23 21:32:24 mbpc-pc kernel:      Not tainted 4.8.4 #2
>>>>> Oct 23 21:32:24 mbpc-pc kernel: "echo 0 >
>>>>> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>>>>> Oct 23 21:32:24 mbpc-pc kernel: kworker/u16:8   D
>>>>> ffff88011113ba18     0
>>>>>   289      2 0x00000000
>>>>> Oct 23 21:32:24 mbpc-pc kernel: Workqueue: tmr-fileio target_tmr_work
>>>>> [target_core_mod]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: ffff88011113ba18 0000000000000400
>>>>> ffff880049e926c0 ffff88011113b998
>>>>> Oct 23 21:32:24 mbpc-pc kernel: ffff880111134600 ffffffff81f99ca0
>>>>> ffffffff81f998ef ffff880100000000
>>>>> Oct 23 21:32:24 mbpc-pc kernel: ffffffff812f27d9 0000000000000000
>>>>> ffffe8ffffc9a000 ffff880000000000
>>>>> Oct 23 21:32:24 mbpc-pc kernel: Call Trace:
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff812f27d9>] ?
>>>>> number+0x2e9/0x310
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162c040>]
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81080169>] ?
>>>>> start_flush_work+0x49/0x180
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162e7ec>]
>>>>> schedule_timeout+0x9c/0xe0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810802ba>] ?
>>>>> flush_work+0x1a/0x40
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810bd15c>] ?
>>>>> console_unlock+0x35c/0x380
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162cfa0>]
>>>>> wait_for_completion+0xc0/0xf0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810923e0>] ?
>>>>> try_to_wake_up+0x260/0x260
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa08f6f84>]
>>>>> __transport_wait_for_tasks+0xb4/0x1b0 [target_core_mod]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810bdd1f>] ?
>>>>> vprintk_default+0x1f/0x30
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8115cc5c>] ?
>>>>> printk+0x46/0x48
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa08f70c4>]
>>>>> transport_wait_for_tasks+0x44/0x60 [target_core_mod]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa08f46e2>]
>>>>> core_tmr_abort_task+0xf2/0x160 [target_core_mod]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa08f6aa4>]
>>>>> target_tmr_work+0x154/0x160 [target_core_mod]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81080639>]
>>>>> process_one_work+0x189/0x4e0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8108150d>]
>>>>> worker_thread+0x16d/0x520
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810923f2>] ?
>>>>> default_wake_function+0x12/0x20
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810a6f06>] ?
>>>>> __wake_up_common+0x56/0x90
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8109130e>] ?
>>>>> schedule_tail+0x1e/0xc0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162f60f>]
>>>>> ret_from_fork+0x1f/0x40
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81085f20>] ?
>>>>> kthread_freezable_should_stop+0x70/0x70
>>>>> Oct 23 21:32:24 mbpc-pc kernel: INFO: task kworker/1:48:6089
>>>>> blocked for
>>>>> more than 120 seconds.
>>>>> Oct 23 21:32:24 mbpc-pc kernel:      Not tainted 4.8.4 #2
>>>>> Oct 23 21:32:24 mbpc-pc kernel: "echo 0 >
>>>>> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>>>>> Oct 23 21:32:24 mbpc-pc kernel: kworker/1:48    D
>>>>> ffff88004017f968     0
>>>>>  6089      2 0x00000080
>>>>> Oct 23 21:32:24 mbpc-pc kernel: Workqueue: events
>>>>> qlt_free_session_done
>>>>> [qla2xxx]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: ffff88004017f968 ffff88004017f8f8
>>>>> ffff88011a83a300 0000000000000004
>>>>> Oct 23 21:32:24 mbpc-pc kernel: ffff88004017a600 ffff88004017f938
>>>>> ffffffff810a0bb6 ffff880100000000
>>>>> Oct 23 21:32:24 mbpc-pc kernel: ffff880110fd0840 ffff880000000000
>>>>> ffffffff81090728 ffff880100000000
>>>>> Oct 23 21:32:24 mbpc-pc kernel: Call Trace:
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810a0bb6>] ?
>>>>> enqueue_task_fair+0x66/0x410
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81090728>] ?
>>>>> check_preempt_curr+0x78/0x90
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8109075d>] ?
>>>>> ttwu_do_wakeup+0x1d/0xf0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162c040>]
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81090de0>] ?
>>>>> ttwu_queue+0x180/0x190
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162e7ec>]
>>>>> schedule_timeout+0x9c/0xe0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162cfa0>]
>>>>> wait_for_completion+0xc0/0xf0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810923e0>] ?
>>>>> try_to_wake_up+0x260/0x260
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa08f76ad>]
>>>>> target_wait_for_sess_cmds+0x4d/0x1b0 [target_core_mod]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa00e7188>] ?
>>>>> qla2x00_post_work+0x58/0x70 [qla2xxx]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa0286f69>]
>>>>> tcm_qla2xxx_free_session+0x49/0x90 [tcm_qla2xxx]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffffa01447e9>]
>>>>> qlt_free_session_done+0xf9/0x3d0 [qla2xxx]
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff815092fc>] ?
>>>>> dbs_work_handler+0x5c/0x90
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8107f960>] ?
>>>>> pwq_dec_nr_in_flight+0x50/0xa0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81080639>]
>>>>> process_one_work+0x189/0x4e0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810d060c>] ?
>>>>> del_timer_sync+0x4c/0x60
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8108131e>] ?
>>>>> maybe_create_worker+0x8e/0x110
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8108150d>]
>>>>> worker_thread+0x16d/0x520
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810923f2>] ?
>>>>> default_wake_function+0x12/0x20
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810a6f06>] ?
>>>>> __wake_up_common+0x56/0x90
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8109130e>] ?
>>>>> schedule_tail+0x1e/0xc0
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff8162f60f>]
>>>>> ret_from_fork+0x1f/0x40
>>>>> Oct 23 21:32:24 mbpc-pc kernel: [<ffffffff81085f20>] ?
>>>>> kthread_freezable_should_stop+0x70/0x70
>>>>> Jan  6 23:56:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
>>>>> successfully started
>>>>> Oct 23 21:34:22 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
>>>>> Oct 23 21:34:22 mbpc-pc kernel: hpet1: lost 3 rtc interrupts
>>>>> Oct 23 21:34:27 mbpc-pc kernel: INFO: task kworker/u16:8:289
>>>>> blocked for
>>>>> more than 120 seconds.
>>>>> Oct 23 21:34:27 mbpc-pc kernel:      Not tainted 4.8.4 #2
>>>>> Oct 23 21:34:27 mbpc-pc kernel: "echo 0 >
>>>>> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>>>>> Oct 23 21:34:27 mbpc-pc kernel: kworker/u16:8   D
>>>>> ffff88011113ba18     0
>>>>>   289      2 0x00000000
>>>>> Oct 23 21:34:27 mbpc-pc kernel: Workqueue: tmr-fileio target_tmr_work
>>>>> [target_core_mod]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: ffff88011113ba18 0000000000000400
>>>>> ffff880049e926c0 ffff88011113b998
>>>>> Oct 23 21:34:27 mbpc-pc kernel: ffff880111134600 ffffffff81f99ca0
>>>>> ffffffff81f998ef ffff880100000000
>>>>> Oct 23 21:34:27 mbpc-pc kernel: ffffffff812f27d9 0000000000000000
>>>>> ffffe8ffffc9a000 ffff880000000000
>>>>> Oct 23 21:34:27 mbpc-pc kernel: Call Trace:
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff812f27d9>] ?
>>>>> number+0x2e9/0x310
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162c040>]
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81080169>] ?
>>>>> start_flush_work+0x49/0x180
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162e7ec>]
>>>>> schedule_timeout+0x9c/0xe0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810802ba>] ?
>>>>> flush_work+0x1a/0x40
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810bd15c>] ?
>>>>> console_unlock+0x35c/0x380
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162cfa0>]
>>>>> wait_for_completion+0xc0/0xf0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810923e0>] ?
>>>>> try_to_wake_up+0x260/0x260
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa08f6f84>]
>>>>> __transport_wait_for_tasks+0xb4/0x1b0 [target_core_mod]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810bdd1f>] ?
>>>>> vprintk_default+0x1f/0x30
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8115cc5c>] ?
>>>>> printk+0x46/0x48
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa08f70c4>]
>>>>> transport_wait_for_tasks+0x44/0x60 [target_core_mod]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa08f46e2>]
>>>>> core_tmr_abort_task+0xf2/0x160 [target_core_mod]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa08f6aa4>]
>>>>> target_tmr_work+0x154/0x160 [target_core_mod]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81080639>]
>>>>> process_one_work+0x189/0x4e0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8108150d>]
>>>>> worker_thread+0x16d/0x520
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810923f2>] ?
>>>>> default_wake_function+0x12/0x20
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810a6f06>] ?
>>>>> __wake_up_common+0x56/0x90
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8109130e>] ?
>>>>> schedule_tail+0x1e/0xc0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162f60f>]
>>>>> ret_from_fork+0x1f/0x40
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81085f20>] ?
>>>>> kthread_freezable_should_stop+0x70/0x70
>>>>> Oct 23 21:34:27 mbpc-pc kernel: INFO: task kworker/1:48:6089
>>>>> blocked for
>>>>> more than 120 seconds.
>>>>> Oct 23 21:34:27 mbpc-pc kernel:      Not tainted 4.8.4 #2
>>>>> Oct 23 21:34:27 mbpc-pc kernel: "echo 0 >
>>>>> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>>>>> Oct 23 21:34:27 mbpc-pc kernel: kworker/1:48    D
>>>>> ffff88004017f968     0
>>>>>  6089      2 0x00000080
>>>>> Oct 23 21:34:27 mbpc-pc kernel: Workqueue: events
>>>>> qlt_free_session_done
>>>>> [qla2xxx]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: ffff88004017f968 ffff88004017f8f8
>>>>> ffff88011a83a300 0000000000000004
>>>>> Oct 23 21:34:27 mbpc-pc kernel: ffff88004017a600 ffff88004017f938
>>>>> ffffffff810a0bb6 ffff880100000000
>>>>> Oct 23 21:34:27 mbpc-pc kernel: ffff880110fd0840 ffff880000000000
>>>>> ffffffff81090728 ffff880100000000
>>>>> Oct 23 21:34:27 mbpc-pc kernel: Call Trace:
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810a0bb6>] ?
>>>>> enqueue_task_fair+0x66/0x410
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81090728>] ?
>>>>> check_preempt_curr+0x78/0x90
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8109075d>] ?
>>>>> ttwu_do_wakeup+0x1d/0xf0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162c040>]
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81090de0>] ?
>>>>> ttwu_queue+0x180/0x190
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162e7ec>]
>>>>> schedule_timeout+0x9c/0xe0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162cfa0>]
>>>>> wait_for_completion+0xc0/0xf0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810923e0>] ?
>>>>> try_to_wake_up+0x260/0x260
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa08f76ad>]
>>>>> target_wait_for_sess_cmds+0x4d/0x1b0 [target_core_mod]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa00e7188>] ?
>>>>> qla2x00_post_work+0x58/0x70 [qla2xxx]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa0286f69>]
>>>>> tcm_qla2xxx_free_session+0x49/0x90 [tcm_qla2xxx]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffffa01447e9>]
>>>>> qlt_free_session_done+0xf9/0x3d0 [qla2xxx]
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff815092fc>] ?
>>>>> dbs_work_handler+0x5c/0x90
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8107f960>] ?
>>>>> pwq_dec_nr_in_flight+0x50/0xa0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81080639>]
>>>>> process_one_work+0x189/0x4e0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810d060c>] ?
>>>>> del_timer_sync+0x4c/0x60
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8108131e>] ?
>>>>> maybe_create_worker+0x8e/0x110
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8108150d>]
>>>>> worker_thread+0x16d/0x520
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810923f2>] ?
>>>>> default_wake_function+0x12/0x20
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810a6f06>] ?
>>>>> __wake_up_common+0x56/0x90
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>>>> maybe_create_worker+0x110/0x110
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8109130e>] ?
>>>>> schedule_tail+0x1e/0xc0
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff8162f60f>]
>>>>> ret_from_fork+0x1f/0x40
>>>>> Oct 23 21:34:27 mbpc-pc kernel: [<ffffffff81085f20>] ?
>>>>> kthread_freezable_should_stop+0x70/0x70
>>>>> Oct 23 21:36:04 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
>>>>> Oct 23 21:36:04 mbpc-pc kernel: hpet1: lost 3 rtc interrupts
>>>>> Jan  6 23:58:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
>>>>> successfully started
>>>>> Oct 23 21:36:30 mbpc-pc kernel: INFO: task kworker/u16:8:289
>>>>> blocked for
>>>>> more than 120 seconds.
>>>>> Oct 23 21:36:30 mbpc-pc kernel:      Not tainted 4.8.4 #2
>>>>> Oct 23 21:36:30 mbpc-pc kernel: "echo 0 >
>>>>> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
>>>>> Oct 23 21:36:30 mbpc-pc kernel: kworker/u16:8   D
>>>>> ffff88011113ba18     0
>>>>>   289      2 0x00000000
>>>>> Oct 23 21:36:30 mbpc-pc kernel: Workqueue: tmr-fileio target_tmr_work
>>>>> [target_core_mod]
>>>>> Oct 23 21:36:30 mbpc-pc kernel: ffff88011113ba18 0000000000000400
>>>>> ffff880049e926c0 ffff88011113b998
>>>>> Oct 23 21:36:30 mbpc-pc kernel: ffff880111134600 ffffffff81f99ca0
>>>>> ffffffff81f998ef ffff880100000000
>>>>> Oct 23 21:36:30 mbpc-pc kernel: ffffffff812f27d9 0000000000000000
>>>>> ffffe8ffffc9a000 ffff880000000000
>>>>> Oct 23 21:36:30 mbpc-pc kernel: Call Trace:
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff812f27d9>] ?
>>>>> number+0x2e9/0x310
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff8162c040>]
>>>>> schedule+0x40/0xb0
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff81080169>] ?
>>>>> start_flush_work+0x49/0x180
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff8162e7ec>]
>>>>> schedule_timeout+0x9c/0xe0
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff810802ba>] ?
>>>>> flush_work+0x1a/0x40
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff810bd15c>] ?
>>>>> console_unlock+0x35c/0x380
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff8162cfa0>]
>>>>> wait_for_completion+0xc0/0xf0
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff810923e0>] ?
>>>>> try_to_wake_up+0x260/0x260
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffffa08f6f84>]
>>>>> __transport_wait_for_tasks+0xb4/0x1b0 [target_core_mod]
>>>>> Oct 23 21:36:30 mbpc-pc kernel: [<ffffffff810bdd1f>] ?
>>>>> vprintk_default+0x1f/0x30
>>>>>
>>>>>
>>>>
>>>>
>>>> Including the full log:
>>>>
>>>> http://microdevsys.com/linux-lio/messages-mailing-list
>>>>
>>>
>>
>> Thanks for posting with qla2xxx verbose debug enabled on your setup.
>>
>>>
>>> When tryint to shut down target using /etc/init.d/target stop, the
>>> following is printed repeatedly:
>>>
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e837:20:
>>> ABTS_RECV_24XX: instance 0
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-f811:20:
>>> qla_target(0): task abort (s_id=1:5:0, tag=1177068, param=0)
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-f812:20:
>>> qla_target(0): task abort for non-existant session
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-f80e:20:
>>> Scheduling work (type 1, prm ffff880093365680) to find session for param
>>> ffff88010f8c7680 (size 64, tgt ffff880111f06600)
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-f800:20: Sess
>>> work (tgt ffff880111f06600)
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e806:20: Sending
>>> task mgmt ABTS response (ha=ffff88010fae0000, atio=ffff880093365694,
>>> status=4
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e838:20:
>>> ABTS_RESP_24XX: compl_status 31
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e807:20: Sending
>>> retry TERM EXCH CTIO7 (ha=ffff88010fae0000)
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e806:20: Sending
>>> task mgmt ABTS response (ha=ffff88010fae0000, atio=ffff88010f8c76c0,
>>> status=0
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e838:20:
>>> ABTS_RESP_24XX: compl_status 0
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e872:20:
>>> qlt_24xx_atio_pkt_all_vps: qla_target(0): type 6 ox_id 029c
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-3861:20: New
>>> command while device ffff880111f06600 is shutting down
>>> Oct 24 00:39:48 mbpc-pc kernel: qla2xxx [0000:04:00.0]-e859:20:
>>> qla_target: Unable to send command to target for req, ignoring.
>>>
>>>
>>
>> At your earliest convenience, please verify the patch using v4.8.y with
>> the above ABORT_TASK + shutdown scenario.
>>
>> Also, it would be helpful to understand why this ESX FC host is
>> generating ABORT_TASKs.
>>
>> Eg: Is ABORT_TASK generated due to FC target response packet loss..?
>> Or due to target backend I/O latency, that ultimately triggers FC host
>> side timeouts...?
>>
>>>
>>> + when I disable the ports on the brocade switch that we're using then
>>> try to stop target, the following is printed:
>>>
>>>
>>>
>>> Oct 24 00:41:31 mbpc-pc kernel: qla2xxx [0000:04:00.1]-680a:21: Loop
>>> down - seconds remaining 231.
>>> Oct 24 00:41:32 mbpc-pc kernel: qla2xxx [0000:04:00.0]-680a:20: Loop
>>> down - seconds remaining 153.
>>> Oct 24 00:41:32 mbpc-pc kernel: ------------[ cut here ]------------
>>> Oct 24 00:41:32 mbpc-pc kernel: WARNING: CPU: 2 PID: 8615 at
>>> lib/list_debug.c:33 __list_add+0xbe/0xd0
>>> Oct 24 00:41:32 mbpc-pc kernel: list_add corruption. prev->next should
>>> be next (ffff88009e83b330), but was ffff88011fc972a0.
>>> (prev=ffff880118ada4c0).
>>> Oct 24 00:41:32 mbpc-pc kernel: Modules linked in: tcm_qla2xxx tcm_fc
>>> tcm_loop target_core_file target_core_iblock target_core_pscsi
>>> target_core_mod configfs ip6table_filter ip6_tables ebtable_nat ebtables
>>> nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack xt_CHECKSUM
>>> iptable_mangle bridge nfsd lockd grace nfs_acl auth_rpcgss autofs4 it87
>>> hwmon_vid bnx2fc cnic uio fcoe libfcoe libfc 8021q garp stp llc ppdev
>>> parport_pc parport sunrpc cpufreq_ondemand bonding ipv6 crc_ccitt
>>> ipt_REJECT nf_reject_ipv4 xt_multiport iptable_filter ip_tables fuse
>>> vfat fat xfs vhost_net macvtap macvlan vhost tun uinput raid456
>>> async_raid6_recov async_pq async_xor xor async_memcpy async_tx raid6_pq
>>> libcrc32c joydev sg serio_raw e1000 kvm_amd kvm irqbypass r8169 mii
>>> pcspkr k10temp snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel
>>> snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm
>>> snd_timer snd soundcore i2c_piix4 i2c_core wmi acpi_cpufreq shpchp ext4
>>> mbcache jbd2 qla2xxx scsi_transport_fc floppy firewire_ohci f
>>> Oct 24 00:41:32 mbpc-pc kernel: irewire_core crc_itu_t sd_mod pata_acpi
>>> ata_generic pata_jmicron ahci libahci usb_storage dm_mirror
>>> dm_region_hash dm_log dm_mod
>>> Oct 24 00:41:32 mbpc-pc kernel: CPU: 2 PID: 8615 Comm: kworker/2:3 Not
>>> tainted 4.8.4 #2
>>> Oct 24 00:41:32 mbpc-pc kernel: Hardware name: Gigabyte Technology Co.,
>>> Ltd. GA-890XA-UD3/GA-890XA-UD3, BIOS FC 08/02/2010
>>> Oct 24 00:41:32 mbpc-pc kernel: 0000000000000000 ffff880092b83b48
>>> ffffffff812e88e9 ffffffff8130753e
>>> Oct 24 00:41:32 mbpc-pc kernel: ffff880092b83ba8 ffff880092b83ba8
>>> 0000000000000000 ffff880092b83b98
>>> Oct 24 00:41:32 mbpc-pc kernel: ffffffff81066a7d ffff88000058f952
>>> 0000002100000046 ffffffff8101eae8
>>> Oct 24 00:41:32 mbpc-pc kernel: Call Trace:
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff812e88e9>]
>>> dump_stack+0x51/0x78
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8130753e>] ?
>>> __list_add+0xbe/0xd0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81066a7d>] __warn+0xfd/0x120
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8101eae8>] ?
>>> __switch_to+0x398/0x7e0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81066b59>]
>>> warn_slowpath_fmt+0x49/0x50
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8130753e>]
>>> __list_add+0xbe/0xd0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8107d0b2>]
>>> move_linked_works+0x62/0x90
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8108070c>]
>>> process_one_work+0x25c/0x4e0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>> schedule+0x40/0xb0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8108150d>]
>>> worker_thread+0x16d/0x520
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162bb3d>] ?
>>> __schedule+0x2fd/0x6a0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810923f2>] ?
>>> default_wake_function+0x12/0x20
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810a6f06>] ?
>>> __wake_up_common+0x56/0x90
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>> maybe_create_worker+0x110/0x110
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>> schedule+0x40/0xb0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>> maybe_create_worker+0x110/0x110
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8109130e>] ?
>>> schedule_tail+0x1e/0xc0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162f60f>]
>>> ret_from_fork+0x1f/0x40
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81085f20>] ?
>>> kthread_freezable_should_stop+0x70/0x70
>>> Oct 24 00:41:32 mbpc-pc kernel: ---[ end trace 713a9071c9f5f464 ]---
>>> Oct 24 00:41:32 mbpc-pc kernel: ------------[ cut here ]------------
>>> Oct 24 00:41:32 mbpc-pc kernel: WARNING: CPU: 2 PID: 8615 at
>>> lib/list_debug.c:36 __list_add+0x9c/0xd0
>>> Oct 24 00:41:32 mbpc-pc kernel: list_add double add:
>>> new=ffff880118ada4c0, prev=ffff880118ada4c0, next=ffff88009e83b330.
>>> Oct 24 00:41:32 mbpc-pc kernel: Modules linked in: tcm_qla2xxx tcm_fc
>>> tcm_loop target_core_file target_core_iblock target_core_pscsi
>>> target_core_mod configfs ip6table_filter ip6_tables ebtable_nat ebtables
>>> nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack xt_CHECKSUM
>>> iptable_mangle bridge nfsd lockd grace nfs_acl auth_rpcgss autofs4 it87
>>> hwmon_vid bnx2fc cnic uio fcoe libfcoe libfc 8021q garp stp llc ppdev
>>> parport_pc parport sunrpc cpufreq_ondemand bonding ipv6 crc_ccitt
>>> ipt_REJECT nf_reject_ipv4 xt_multiport iptable_filter ip_tables fuse
>>> vfat fat xfs vhost_net macvtap macvlan vhost tun uinput raid456
>>> async_raid6_recov async_pq async_xor xor async_memcpy async_tx raid6_pq
>>> libcrc32c joydev sg serio_raw e1000 kvm_amd kvm irqbypass r8169 mii
>>> pcspkr k10temp snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel
>>> snd_hda_codec snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm
>>> snd_timer snd soundcore i2c_piix4 i2c_core wmi acpi_cpufreq shpchp ext4
>>> mbcache jbd2 qla2xxx scsi_transport_fc floppy firewire_ohci f
>>> Oct 24 00:41:32 mbpc-pc kernel: irewire_core crc_itu_t sd_mod pata_acpi
>>> ata_generic pata_jmicron ahci libahci usb_storage dm_mirror
>>> dm_region_hash dm_log dm_mod
>>> Oct 24 00:41:32 mbpc-pc kernel: CPU: 2 PID: 8615 Comm: kworker/2:3
>>> Tainted: G        W       4.8.4 #2
>>> Oct 24 00:41:32 mbpc-pc kernel: Hardware name: Gigabyte Technology Co.,
>>> Ltd. GA-890XA-UD3/GA-890XA-UD3, BIOS FC 08/02/2010
>>> Oct 24 00:41:32 mbpc-pc kernel: 0000000000000000 ffff880092b83b48
>>> ffffffff812e88e9 ffffffff8130751c
>>> Oct 24 00:41:32 mbpc-pc kernel: ffff880092b83ba8 ffff880092b83ba8
>>> 0000000000000000 ffff880092b83b98
>>> Oct 24 00:41:32 mbpc-pc kernel: ffffffff81066a7d ffff88000058f952
>>> 0000002400000046 ffffffff8101eae8
>>> Oct 24 00:41:32 mbpc-pc kernel: Call Trace:
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff812e88e9>]
>>> dump_stack+0x51/0x78
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8130751c>] ?
>>> __list_add+0x9c/0xd0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81066a7d>] __warn+0xfd/0x120
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8101eae8>] ?
>>> __switch_to+0x398/0x7e0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81066b59>]
>>> warn_slowpath_fmt+0x49/0x50
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8130751c>]
>>> __list_add+0x9c/0xd0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8107d0b2>]
>>> move_linked_works+0x62/0x90
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8108070c>]
>>> process_one_work+0x25c/0x4e0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>> schedule+0x40/0xb0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8108150d>]
>>> worker_thread+0x16d/0x520
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162bb3d>] ?
>>> __schedule+0x2fd/0x6a0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810923f2>] ?
>>> default_wake_function+0x12/0x20
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810a6f06>] ?
>>> __wake_up_common+0x56/0x90
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>> maybe_create_worker+0x110/0x110
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162c040>] ?
>>> schedule+0x40/0xb0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff810813a0>] ?
>>> maybe_create_worker+0x110/0x110
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8109130e>] ?
>>> schedule_tail+0x1e/0xc0
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff8162f60f>]
>>> ret_from_fork+0x1f/0x40
>>> Oct 24 00:41:32 mbpc-pc kernel: [<ffffffff81085f20>] ?
>>> kthread_freezable_should_stop+0x70/0x70
>>> Oct 24 00:41:32 mbpc-pc kernel: ---[ end trace 713a9071c9f5f465 ]---
>>> Oct 24 00:41:32 mbpc-pc kernel: qla2xxx [0000:04:00.1]-680a:21: Loop
>>> down - seconds remaining 230.
>>> Oct 24 00:41:33 mbpc-pc kernel: qla2xxx [0000:04:00.0]-680a:20: Loop
>>> down - seconds remaining 152.
>>>
>>>
>>
>> Mmmm.  Could be a side effect of the target-core regression, but not
>> completely sure..
>>
>> Adding QLOGIC folks CC'.
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>
>
> Hey Nicholas,
>
>
>> At your earliest convenience, please verify the patch using v4.8.y with
>> the above ABORT_TASK + shutdown scenario.
>>
>> Also, it would be helpful to understand why this ESX FC host is
>> generating ABORT_TASKs.
>>
>> Eg: Is ABORT_TASK generated due to FC target response packet loss..?
>> Or due to target backend I/O latency, that ultimately triggers FC host
>> side timeouts...?
>
>
> Here is where it gets interesting and to your thought above.  Take for
> example this log snippet
> (http://microdevsys.com/linux-lio/messages-recent):
>
> Oct 23 22:12:51 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Jan  7 00:36:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
> successfully started
> Oct 23 22:14:14 mbpc-pc kernel: hpet1: lost 9599 rtc interrupts
> Oct 23 22:14:14 mbpc-pc kernel: hpet1: lost 1 rtc interrupts
> Oct 23 22:15:02 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Oct 23 22:15:41 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Jan  7 00:38:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
> successfully started
> Oct 23 22:16:29 mbpc-pc kernel: hpet1: lost 9599 rtc interrupts
> Oct 23 22:17:30 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Jan  7 00:40:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
> successfully started
> Oct 23 22:18:29 mbpc-pc kernel: ABORT_TASK: Found referenced qla2xxx
> task_tag: 1195032
> Oct 23 22:18:33 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Oct 23 22:18:42 mbpc-pc kernel: ABORT_TASK: Sending
> TMR_FUNCTION_COMPLETE for ref_tag: 1195032
> Oct 23 22:18:42 mbpc-pc kernel: ABORT_TASK: Found referenced qla2xxx
> task_tag: 1122276
> Oct 23 22:19:35 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Jan  7 00:42:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
> successfully started
> Oct 23 22:20:41 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Oct 23 22:21:07 mbpc-pc kernel: INFO: task kworker/u16:8:308 blocked for
> more than 120 seconds.
> Oct 23 22:21:07 mbpc-pc kernel:      Not tainted 4.8.4 #2
> Oct 23 22:21:07 mbpc-pc kernel: "echo 0 >
> /proc/sys/kernel/hung_task_timeout_secs" disables this message.
> Oct 23 22:21:07 mbpc-pc kernel: kworker/u16:8   D ffff880111b8fa18     0
>   308      2 0x00000000
> Oct 23 22:21:07 mbpc-pc kernel: Workqueue: tmr-fileio target_tmr_work
> [target_core_mod]
> Oct 23 22:21:07 mbpc-pc kernel: ffff880111b8fa18 0000000000000400
> ffff880112180480 ffff880111b8f998
> Oct 23 22:21:07 mbpc-pc kernel: ffff88011107a380 ffffffff81f99ca0
> ffffffff81f998ef ffff880100000000
> Oct 23 22:21:07 mbpc-pc kernel: ffffffff812f27d9 0000000000000000
> ffffe8ffffcda000 ffff880000000000
> Oct 23 22:21:07 mbpc-pc kernel: Call Trace:
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff812f27d9>] ? number+0x2e9/0x310
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8162c040>] schedule+0x40/0xb0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff81080169>] ?
> start_flush_work+0x49/0x180
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8162e7ec>]
> schedule_timeout+0x9c/0xe0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810802ba>] ? flush_work+0x1a/0x40
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810bd15c>] ?
> console_unlock+0x35c/0x380
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8162cfa0>]
> wait_for_completion+0xc0/0xf0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810923e0>] ?
> try_to_wake_up+0x260/0x260
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffffa08f6f84>]
> __transport_wait_for_tasks+0xb4/0x1b0 [target_core_mod]
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810bdd1f>] ?
> vprintk_default+0x1f/0x30
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8115cc5c>] ? printk+0x46/0x48
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffffa08f70c4>]
> transport_wait_for_tasks+0x44/0x60 [target_core_mod]
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffffa08f46e2>]
> core_tmr_abort_task+0xf2/0x160 [target_core_mod]
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffffa08f6aa4>]
> target_tmr_work+0x154/0x160 [target_core_mod]
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff81080639>]
> process_one_work+0x189/0x4e0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810d060c>] ?
> del_timer_sync+0x4c/0x60
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8108131e>] ?
> maybe_create_worker+0x8e/0x110
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8162c040>] ? schedule+0x40/0xb0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8108150d>]
> worker_thread+0x16d/0x520
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810923f2>] ?
> default_wake_function+0x12/0x20
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810a6f06>] ?
> __wake_up_common+0x56/0x90
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810813a0>] ?
> maybe_create_worker+0x110/0x110
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8162c040>] ? schedule+0x40/0xb0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff810813a0>] ?
> maybe_create_worker+0x110/0x110
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff81085fec>] kthread+0xcc/0xf0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8109130e>] ?
> schedule_tail+0x1e/0xc0
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff8162f60f>]
> ret_from_fork+0x1f/0x40
> Oct 23 22:21:07 mbpc-pc kernel: [<ffffffff81085f20>] ?
> kthread_freezable_should_stop+0x70/0x70
> Oct 23 22:21:52 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
> Jan  7 00:44:00 192.168.0.2 syslog: dhcpfwd : dhcp forwarder daemon
> successfully started
> Oct 23 22:23:03 mbpc-pc kernel: hpet1: lost 9600 rtc interrupts
>
>
> And compare it to the following snippet
> (http://microdevsys.com/linux-lio/iostat-tkx-interesting-bit.txt) taken
> from this bigger iostat session
> (http://microdevsys.com/linux-lio/iostat-tkx.txt):
>
>
>
>
> 10/23/2016 10:18:19 PM
> avg-cpu:  %user   %nice %system %iowait  %steal   %idle
>            0.25    0.00    0.50   15.83    0.00   83.42
>
> Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
> avgrq-sz avgqu-sz   await  svctm  %util
> sdb               0.00     0.00    2.00    0.00    80.00     0.00
> 80.00     0.02   12.00  12.00   2.40
> sdc               0.00     0.00    1.00    0.00    64.00     0.00
> 128.00     0.00    2.00   2.00   0.20
> sdd               0.00     0.00    1.00    0.00    48.00     0.00
> 96.00     0.00    0.00   0.00   0.00
> sde               0.00     0.00    2.00    0.00    64.00     0.00
> 64.00     0.00    1.50   1.50   0.30
> sdf               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.60    0.00   0.00  60.10
> sdg               0.00     3.00    0.00    3.00     0.00    20.00
> 13.33     0.03   10.00  10.00   3.00
> sda               0.00     0.00    2.00    0.00    64.00     0.00
> 64.00     0.00    2.00   2.00   0.40
> sdh               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdj               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdk               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdi               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> fd0               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-0              0.00     0.00    0.00    5.00     0.00    20.00
> 8.00     0.03    6.40   6.00   3.00
> dm-1              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-2              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> md0               0.00     0.00    3.00    0.00   384.00     0.00
> 256.00     0.00    0.00   0.00   0.00
> dm-3              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-4              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-5              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-6              0.00     0.00    3.00    0.00   384.00     0.00
> 256.00     0.60    1.33 201.67  60.50
>
> 10/23/2016 10:18:20 PM
> avg-cpu:  %user   %nice %system %iowait  %steal   %idle
>            0.00    0.00    0.25   25.19    0.00   74.56
>
> Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
> avgrq-sz avgqu-sz   await  svctm  %util
> sdb               0.00     0.00    0.00    1.00     0.00     2.50
> 5.00     0.03   27.00  27.00   2.70
> sdc               0.00     0.00    0.00    1.00     0.00     2.50
> 5.00     0.01   15.00  15.00   1.50
> sdd               0.00     0.00    0.00    1.00     0.00     2.50
> 5.00     0.02   18.00  18.00   1.80
> sde               0.00     0.00    0.00    1.00     0.00     2.50
> 5.00     0.02   23.00  23.00   2.30
> sdf               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     1.15    0.00   0.00 100.00
> sdg               0.00     2.00    1.00    4.00     4.00   172.00
> 70.40     0.04    8.40   2.80   1.40
> sda               0.00     0.00    0.00    1.00     0.00     2.50
> 5.00     0.04   37.00  37.00   3.70
> sdh               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdj               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdk               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdi               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> fd0               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-0              0.00     0.00    1.00    6.00     4.00   172.00
> 50.29     0.05    7.29   2.00   1.40
> dm-1              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-2              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> md0               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-3              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-4              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-5              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-6              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     1.00    0.00   0.00 100.00
>
> 10/23/2016 10:18:21 PM
> avg-cpu:  %user   %nice %system %iowait  %steal   %idle
>            0.00    0.00    0.25   24.81    0.00   74.94
>
> Device:         rrqm/s   wrqm/s     r/s     w/s    rkB/s    wkB/s
> avgrq-sz avgqu-sz   await  svctm  %util
> sdb               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdc               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdd               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sde               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdf               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     2.00    0.00   0.00 100.00
> sdg               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sda               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdh               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdj               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdk               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> sdi               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> fd0               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-0              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-1              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-2              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> md0               0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-3              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-4              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-5              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     0.00    0.00   0.00   0.00
> dm-6              0.00     0.00    0.00    0.00     0.00     0.00
> 0.00     1.00    0.00   0.00 100.00
>
>
> We can see that /dev/sdf ramps up to 100% starting at around (10/23/2016
> 10:18:18 PM) and stays that way till about the (10/23/2016 10:18:42 PM)
> mark when something occurs and it drops down to below 100% numbers.
>
> So I checked the array which shows all clean, even across reboots:
>
> [root@mbpc-pc ~]# cat /proc/mdstat
> Personalities : [raid6] [raid5] [raid4]
> md0 : active raid6 sdb[7] sdf[6] sdd[3] sda[5] sdc[1] sde[8]
>       3907045632 blocks super 1.2 level 6, 64k chunk, algorithm 2 [6/6]
> [UUUUUU]
>       bitmap: 1/8 pages [4KB], 65536KB chunk
>
> unused devices: <none>
> [root@mbpc-pc ~]#
>
>
> Then I run smartctl across all disks and sure enough /dev/sdf prints this:
>
> [root@mbpc-pc ~]# smartctl -A /dev/sdf
> smartctl 5.43 2012-06-30 r3573 [x86_64-linux-4.8.4] (local build)
> Copyright (C) 2002-12 by Bruce Allen, http://smartmontools.sourceforge.net
>
> Error SMART Values Read failed: scsi error badly formed scsi parameters
> Smartctl: SMART Read Values failed.
>
> === START OF READ SMART DATA SECTION ===
> [root@mbpc-pc ~]#
>
> So it would appear we found the root cause, a bad disk.  True the disk
> is bad and I'll be replacing it however, even with a degraded disk
> (checking now) the array functions just fine and I have no data loss.  I
> only lost 1.  I would have to loose 3 to get a catastrophic failure on
> this RAID6:
>
> [root@mbpc-pc ~]# cat /proc/mdstat
> Personalities : [raid6] [raid5] [raid4]
> md0 : active raid6 sdf[6](F) sda[5] sde[8] sdb[7] sdd[3] sdc[1]
>       3907045632 blocks super 1.2 level 6, 64k chunk, algorithm 2 [6/5]
> [UUUU_U]
>       bitmap: 6/8 pages [24KB], 65536KB chunk
>
> unused devices: <none>
> [root@mbpc-pc ~]# mdadm --detail /dev/md0
> /dev/md0:
>         Version : 1.2
>   Creation Time : Mon Mar 26 00:06:24 2012
>      Raid Level : raid6
>      Array Size : 3907045632 (3726.05 GiB 4000.81 GB)
>   Used Dev Size : 976761408 (931.51 GiB 1000.20 GB)
>    Raid Devices : 6
>   Total Devices : 6
>     Persistence : Superblock is persistent
>
>   Intent Bitmap : Internal
>
>     Update Time : Tue Oct 25 00:31:13 2016
>           State : clean, degraded
>  Active Devices : 5
> Working Devices : 5
>  Failed Devices : 1
>   Spare Devices : 0
>
>          Layout : left-symmetric
>      Chunk Size : 64K
>
>            Name : mbpc:0
>            UUID : 2f36ac48:5e3e4c54:72177c53:bea3e41e
>          Events : 118368
>
>     Number   Major   Minor   RaidDevice State
>        8       8       64        0      active sync   /dev/sde
>        1       8       32        1      active sync   /dev/sdc
>        7       8       16        2      active sync   /dev/sdb
>        3       8       48        3      active sync   /dev/sdd
>        8       0        0        8      removed
>        5       8        0        5      active sync   /dev/sda
>
>        6       8       80        -      faulty   /dev/sdf
> [root@mbpc-pc ~]#
>
> Last night I cut power to the /dev/sdf disk to spin it down the removed
> it and reinserted it.  The array resynced without issue however the
> smartctl -A command still failed on it. Today I check and bad blocks
> were recorded on the disk and the array has since removed /dev/sdf (per
> above).  Also I have to say that these ESXi hosts worked in this
> configuration, without any hickup, for about 4 months.  No LUN failure
> on the ESXi side.  I haven't changed the LUN in that time (had no reason
> to do so).
>
> So now here's the real question that I have.  Why would the array
> continue to function, as intended, with only one disk failure yet the
> QLogic / Target drivers stop and error out?  The RAID6 (software) array
> should care about the failure, and it should handle it.  QLogic / Target
> Drivers shouldn't really be too impacted (aside from read speed maybe)
> about a disk failing inside the array.  That would be my thinking.  The
> Target / QLogic software seems to have picked up on a failure ahead of
> the software RAID 6 detecting it.  I've had this RAID6 for over 6 years
> now.  Aside from the occassional disk replacement, quite rock solid.
>
> So anyway, I added the fix you pointed out to the 4.8.4 kernel and
> recompiled.  I restarted it, with the RAID6 degraded as it is.  All
> mounted fine and I checked the LUN's from the ESXi side:
>
> [root@mbpc-pc ~]# /etc/init.d/target start
> The Linux SCSI Target is already stopped                   [  OK  ]
> [info] The Linux SCSI Target looks properly installed.
> The configfs filesystem was not mounted, consider adding it[WARNING]
> [info] Loaded core module target_core_mod.
> [info] Loaded core module target_core_pscsi.
> [info] Loaded core module target_core_iblock.
> [info] Loaded core module target_core_file.
> Failed to load fabric module ib_srpt                       [WARNING]
> Failed to load fabric module tcm_usb_gadget                [WARNING]
> [info] Loaded fabric module tcm_loop.
> [info] Loaded fabric module tcm_fc.
> Failed to load fabric module vhost_scsi                    [WARNING]
> [info] Loaded fabric module tcm_qla2xxx.
> Failed to load fabric module iscsi_target_mod              [WARNING]
> [info] Loading config from /etc/target/scsi_target.lio, this may take
> several minutes for FC adapters.
> [info] Loaded /etc/target/scsi_target.lio.
> Started The Linux SCSI Target                              [  OK  ]
> [root@mbpc-pc ~]#
>
>
> Enabled the brocade ports:
>
>
>  18  18   011200   id    N4   No_Light    FC
>  19  19   011300   id    N4   No_Sync     FC  Disabled (Persistent)
>  20  20   011400   id    N4   No_Light    FC
>  21  21   011500   id    N4   No_Light    FC
>  22  22   011600   id    N4   No_Light    FC
>  23  23   011700   id    N4   No_Light    FC  Disabled (Persistent)
>  24  24   011800   --    N4   No_Module   FC  (No POD License) Disabled
>  25  25   011900   --    N4   No_Module   FC  (No POD License) Disabled
>  26  26   011a00   --    N4   No_Module   FC  (No POD License) Disabled
>  27  27   011b00   --    N4   No_Module   FC  (No POD License) Disabled
>  28  28   011c00   --    N4   No_Module   FC  (No POD License) Disabled
>  29  29   011d00   --    N4   No_Module   FC  (No POD License) Disabled
>  30  30   011e00   --    N4   No_Module   FC  (No POD License) Disabled
>  31  31   011f00   --    N4   No_Module   FC  (No POD License) Disabled
> sw0:admin> portcfgpersistentenable 19
> sw0:admin> portcfgpersistentenable 23
> sw0:admin> date
> Tue Oct 25 04:03:42 UTC 2016
> sw0:admin>
>
> And still after 30 minutes, there is no failure.  This run includes the
> fix you asked me to ass
> (https://github.com/torvalds/linux/commit/527268df31e57cf2b6d417198717c6d6afdb1e3e)
>  .  If everything works, I will revert the patch and see if I can
> reproduce the issue.  If I can reproduce it, then the disk might not
> have been it, but the patch was.  I'll keep you posted on that when I
> get a new disk tomorrow.
>
>
> Right now this is a POC setup so I have lots of room to experiment.
>

Hey Nicholas,

I've done some testing up till now.  With or without the patch above, as 
long as the faulty disk is removed from the RAID 6 software array, 
everything works fine with the Target Driver and ESXi hosts.  This is 
even on a degraded array:

[root@mbpc-pc ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md0 : active raid6 sdc[1] sda[5] sdd[3] sde[8] sdb[7]
       3907045632 blocks super 1.2 level 6, 64k chunk, algorithm 2 [6/5] 
[UUUU_U]
       bitmap: 6/8 pages [24KB], 65536KB chunk

unused devices: <none>
[root@mbpc-pc ~]#

So at the moment, the data points to the single failed single disk ( 
/dev/sdf ) as causing the Target Drivers or QLogic cards to throw an 
exception.

Tomorrow I will insert the failed disk back in to see if the a) array 
takes it back, b) it causes a failure with the patch applied.

Looks like the failed disk /dev/sdf was limping along for months and 
until I removed the power, it didn't collapse on itself.

-- 
Cheers,
Tom K.
-------------------------------------------------------------------------------------

Living on earth is expensive, but it includes a free trip around the sun.


  reply	other threads:[~2016-10-26  2:10 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-10-24  2:03 Kernel 4.8.4: INFO: task kworker/u16:8:289 blocked for more than 120 seconds TomK
2016-10-24  4:32 ` TomK
2016-10-24  4:45   ` TomK
2016-10-24  6:36     ` Nicholas A. Bellinger
2016-10-25  5:28       ` TomK
2016-10-26  2:05         ` TomK [this message]
2016-10-26  7:20           ` Nicholas A. Bellinger
2016-10-26 12:08             ` TomK
2016-10-28  6:01               ` TomK
2016-10-29  7:50                 ` Nicholas A. Bellinger
2016-10-29 18:10                   ` TomK
2016-10-29 21:44                     ` Nicholas A. Bellinger
2016-10-30 18:50                       ` TomK
2016-11-01  2:44                         ` TomK

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