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INFO: task hung in imon_probe (2)

Status: closed as invalid on 2022/02/08 09:50
Subsystems: media
[Documentation on labels]
First crash: 1336d, last: 1336d
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in imon_probe media 1 3 1431d 1432d 0/29 auto-closed as invalid on 2021/12/25 07:23
upstream INFO: task hung in imon_probe (3) media 1 1 1294d 1294d 0/29 auto-closed as invalid on 2022/05/11 23:40

Sample crash report:
INFO: task kworker/0:5:3691 blocked for more than 143 seconds.
      Not tainted 5.16.0-rc7-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:5     state:D stack:24016 pid: 3691 ppid:     2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4972 [inline]
 __schedule+0xa9a/0x4900 kernel/sched/core.c:6253
 schedule+0xd2/0x260 kernel/sched/core.c:6326
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6385
 __mutex_lock_common kernel/locking/mutex.c:680 [inline]
 __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:740
 imon_probe+0x14a/0x2b90 drivers/media/rc/imon.c:2420
 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:517 [inline]
 really_probe+0x245/0xcc0 drivers/base/dd.c:596
 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
 __device_attach+0x228/0x4a0 drivers/base/dd.c:969
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
 device_add+0xc17/0x1ee0 drivers/base/core.c:3394
 usb_set_configuration+0x101e/0x1900 drivers/usb/core/message.c:2170
 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:517 [inline]
 really_probe+0x245/0xcc0 drivers/base/dd.c:596
 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:751
 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:781
 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:898
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427
 __device_attach+0x228/0x4a0 drivers/base/dd.c:969
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487
 device_add+0xc17/0x1ee0 drivers/base/core.c:3394
 usb_new_device.cold+0x63f/0x108e drivers/usb/core/hub.c:2563
 hub_port_connect drivers/usb/core/hub.c:5353 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5497 [inline]
 port_event drivers/usb/core/hub.c:5643 [inline]
 hub_event+0x23e5/0x4460 drivers/usb/core/hub.c:5725
 process_one_work+0x9b2/0x1660 kernel/workqueue.c:2298
 worker_thread+0x65d/0x1130 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8bb83da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
2 locks held by kworker/u4:2/44:
2 locks held by getty/3285:
 #0: ffff88814a890098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002b962e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113
3 locks held by udevd/3665:
 #0: ffff88807c215888 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:203 [inline]
 #0: ffff88807c215888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x185/0x5f0 fs/kernfs/file.c:242
 #1: ffff88807f5aecb8 (kn->active#56){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:204 [inline]
 #1: ffff88807f5aecb8 (kn->active#56){++++}-{0:0}, at: kernfs_fop_read_iter+0x1a8/0x5f0 fs/kernfs/file.c:242
 #2: ffff888044a33220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
 #2: ffff888044a33220 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:873
6 locks held by kworker/0:5/3691:
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x896/0x1660 kernel/workqueue.c:2269
 #1: ffffc90002befdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1660 kernel/workqueue.c:2273
 #2: ffff888147523220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff888147523220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4460 drivers/usb/core/hub.c:5671
 #3: ffff888044a33220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #3: ffff888044a33220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
 #4: ffff8880225691a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #4: ffff8880225691a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
 #5: ffffffff8ccfeb68 (driver_lock){+.+.}-{3:3}, at: imon_probe+0x14a/0x2b90 drivers/media/rc/imon.c:2420
6 locks held by kworker/0:8/3696:
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x896/0x1660 kernel/workqueue.c:2269
 #1: ffffc90002c4fdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1660 kernel/workqueue.c:2273
 #2: ffff88801dc53220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff88801dc53220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4460 drivers/usb/core/hub.c:5671
 #3: ffff88807be19220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #3: ffff88807be19220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
 #4: ffff8880772881a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #4: ffff8880772881a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:944
 #5: ffffffff8ccfeb68 (driver_lock){+.+.}-{3:3}, at: imon_probe+0x14a/0x2b90 drivers/media/rc/imon.c:2420
3 locks held by udevd/4390:
 #0: ffff888077ee2488 (&of->mutex){+.+.}-{3:3}, at: kernfs_file_read_iter fs/kernfs/file.c:203 [inline]
 #0: ffff888077ee2488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_read_iter+0x185/0x5f0 fs/kernfs/file.c:242
 #1: ffff88801e0f0008 (kn->active#56){++++}-{0:0}, at: kernfs_file_read_iter fs/kernfs/file.c:204 [inline]
 #1: ffff88801e0f0008 (kn->active#56){++++}-{0:0}, at: kernfs_fop_read_iter+0x1a8/0x5f0 fs/kernfs/file.c:242
 #2: ffff88807be19220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
 #2: ffff88807be19220 (&dev->mutex){....}-{3:3}, at: read_descriptors+0x3c/0x2c0 drivers/usb/core/sysfs.c:873
3 locks held by kworker/0:11/6031:
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
 #0: ffff888015c0b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x896/0x1660 kernel/workqueue.c:2269
 #1: ffffc9000f6dfdb0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1660 kernel/workqueue.c:2273
 #2: ffff88801ddb3220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
 #2: ffff88801ddb3220 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4460 drivers/usb/core/hub.c:5671
1 lock held by syz-executor.4/15132:
 #0: ffffffff8bb8d030 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x44/0x430 kernel/rcu/tree.c:3985

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xc1d/0xf50 kernel/hung_task.c:295
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 966 Comm: kworker/u4:4 Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: phy13 ieee80211_iface_work
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:55 [inline]
RIP: 0010:__unwind_start+0x542/0x800 arch/x86/kernel/unwind_orc.c:710
Code: de ff ff 4c 89 f8 48 c1 e8 03 0f b6 04 28 84 c0 74 08 3c 03 0f 8e 2d 01 00 00 41 8b 07 85 c0 0f 84 89 fd ff ff 41 80 7d 00 00 <0f> 85 3d 01 00 00 41 80 3c 24 00 49 8b 47 08 0f 85 15 01 00 00 48
RSP: 0018:ffffc900048b73b8 EFLAGS: 00000246
RAX: 1ffff92000916e82 RBX: ffffc900048b7490 RCX: ffffc900048b8000
RDX: 0000000000000001 RSI: 1ffff92000916e83 RDI: ffffc900048b73b8
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffc900048b7408
R10: fffff52000916e8c R11: 000000000000003f R12: fffff52000916e83
R13: fffff52000916e82 R14: ffffc900048b7440 R15: ffffc900048b7408
FS:  0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555556f848 CR3: 000000007e77a000 CR4: 00000000003526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0x5c/0xe0 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749
 slab_free mm/slub.c:3513 [inline]
 kfree+0xf6/0x560 mm/slub.c:4561
 ieee802_11_parse_elems_crc+0xb15/0x1050 net/mac80211/util.c:1522
 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2208 [inline]
 ieee80211_bss_info_update+0x42c/0xb00 net/mac80211/scan.c:212
 ieee80211_rx_bss_info net/mac80211/ibss.c:1119 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1610 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x19cf/0x3150 net/mac80211/ibss.c:1639
 ieee80211_iface_process_skb net/mac80211/iface.c:1468 [inline]
 ieee80211_iface_work+0xa65/0xd00 net/mac80211/iface.c:1522
 process_one_work+0x9b2/0x1660 kernel/workqueue.c:2298
 worker_thread+0x65d/0x1130 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:	de ff                	fdivrp %st,%st(7)
   2:	ff 4c 89 f8          	decl   -0x8(%rcx,%rcx,4)
   6:	48 c1 e8 03          	shr    $0x3,%rax
   a:	0f b6 04 28          	movzbl (%rax,%rbp,1),%eax
   e:	84 c0                	test   %al,%al
  10:	74 08                	je     0x1a
  12:	3c 03                	cmp    $0x3,%al
  14:	0f 8e 2d 01 00 00    	jle    0x147
  1a:	41 8b 07             	mov    (%r15),%eax
  1d:	85 c0                	test   %eax,%eax
  1f:	0f 84 89 fd ff ff    	je     0xfffffdae
  25:	41 80 7d 00 00       	cmpb   $0x0,0x0(%r13)
* 2a:	0f 85 3d 01 00 00    	jne    0x16d <-- trapping instruction
  30:	41 80 3c 24 00       	cmpb   $0x0,(%r12)
  35:	49 8b 47 08          	mov    0x8(%r15),%rax
  39:	0f 85 15 01 00 00    	jne    0x154
  3f:	48                   	rex.W

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/30 18:24 upstream eec4df26e24e 2e49f10d .config console log report info ci-upstream-kasan-gce INFO: task hung in imon_probe
* Struck through repros no longer work on HEAD.