syzbot


INFO: task hung in do_task_dead

Status: auto-closed as invalid on 2020/12/09 18:36
Reported-by: syzbot+ea07d1d8ed11998881ff@syzkaller.appspotmail.com
First crash: 682d, last: 682d
similar bugs (3):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_task_dead 1 1187d 1187d 0/22 auto-closed as invalid on 2019/09/21 14:08
upstream INFO: task hung in do_task_dead (3) 2 816d 817d 0/22 auto-closed as invalid on 2020/06/28 13:10
upstream INFO: task hung in do_task_dead (2) 1 935d 935d 0/22 auto-closed as invalid on 2020/03/01 19:02

Sample crash report:
0 pages cma reserved
Out of memory: Kill process 23941 (syz-executor.2) score 1007 or sacrifice child
Killed process 23941 (syz-executor.2) total-vm:93940kB, anon-rss:16488kB, file-rss:34608kB, shmem-rss:0kB
INFO: task kworker/u4:9:23935 blocked for more than 140 seconds.
      Not tainted 4.14.193-syzkaller #0
oom_reaper: reaped process 23941 (syz-executor.2), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:9    D27480 23935  23708 0x80000000
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3384
systemd[1]: systemd-journald.service: Main process exited, code=killed, status=6/ABRT
 do_task_dead+0xc3/0xf0 kernel/sched/core.c:3401
 do_exit+0x15f0/0x27f0 kernel/exit.c:916
systemd[1]: systemd-journald.service: Unit entered failed state.
systemd[1]: systemd-journald.service: Failed with result 'watchdog'.
systemd[1]: systemd-journald.service: Service has no hold-off time, scheduling restart.
 do_group_exit+0x100/0x2e0 kernel/exit.c:962
 SYSC_exit_group kernel/exit.c:973 [inline]
 SyS_exit_group+0x19/0x20 kernel/exit.c:971
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f8405bef618
RSP: 002b:00007ffe307b43a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f8405bef618
systemd[1]: Stopped Flush Journal to Persistent Storage.
systemd[1]: Stopping Flush Journal to Persistent Storage...
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
systemd[1]: Stopped Journal Service.
RBP: 00007f8405ecc8e0 R08: 00000000000000e7 R09: ffffffffffffff98
R10: 00007ffe307b4328 R11: 0000000000000246 R12: 00007f8405ecc8e0
R13: 00007f8405ed1c20 R14: 0000000000000000 R15: 0000000000000000
systemd[1]: Starting Journal Service...

Showing all locks held in the system:
2 locks held by kworker/0:0/3:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:1/23:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
1 lock held by khungtaskd/1068:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff814778d4>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
2 locks held by kworker/1:2/2739:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:2/2874:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:3/3668:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by agetty/6073:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff8343ce32>] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:284
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83432183>] n_tty_read+0x1e3/0x1680 drivers/tty/n_tty.c:2156
1 lock held by syz-fuzzer/6359:
 #0:  (&ei->i_mmap_sem){++++}, at: [<ffffffff81c309bc>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6237
1 lock held by syz-fuzzer/6363:
 #0:  (&ei->i_mmap_sem){++++}, at: [<ffffffff81c309bc>] ext4_filemap_fault+0x7c/0xb0 fs/ext4/inode.c:6237
2 locks held by kworker/1:3/7366:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:4/7481:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:4/7567:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/u4:1/3866:
 #0:  ("events_unbound"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((reaper_work).work){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:0/4291:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/u4:7/7972:
 #0:  ("events_unbound"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  (connector_reaper_work){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:5/8938:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:6/8943:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:1/9050:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:5/10427:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:6/14192:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:7/19340:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:7/19634:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:8/21418:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:8/21421:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:9/21422:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:9/21423:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:10/21424:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:11/21425:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:12/21426:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:10/21427:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:13/21428:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:14/21429:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:15/21430:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:11/21431:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:16/21432:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:12/21433:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:17/21434:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:13/21435:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:18/21436:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
3 locks held by kworker/0:19/21437:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (rcu_preempt_state.exp_mutex){+.+.}, at: [<ffffffff814d288d>] exp_funnel_lock kernel/rcu/tree_exp.h:305 [inline]
 #2:  (rcu_preempt_state.exp_mutex){+.+.}, at: [<ffffffff814d288d>] _synchronize_rcu_expedited+0x32d/0x770 kernel/rcu/tree_exp.h:596
2 locks held by kworker/1:14/21438:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:20/21439:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:15/21440:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:21/21441:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:16/21442:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:22/21443:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:17/21444:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:23/21445:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:18/21446:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:24/21447:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:19/21448:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:20/21449:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:21/21450:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:22/21451:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:23/21452:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:24/21453:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:25/21454:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
3 locks held by syz-executor.0/23630:
 #0:  (&hdev->req_lock){+.+.}, at: [<ffffffff85af5c0d>] hci_dev_do_close+0xfd/0xc50 net/bluetooth/hci_core.c:1576
 #1:  (&hdev->lock){+.+.}, at: [<ffffffff85af5d20>] hci_dev_do_close+0x210/0xc50 net/bluetooth/hci_core.c:1607
 #2:  (hci_cb_list_lock){+.+.}, at: [<ffffffff85b09f87>] hci_disconn_cfm include/net/bluetooth/hci_core.h:1223 [inline]
 #2:  (hci_cb_list_lock){+.+.}, at: [<ffffffff85b09f87>] hci_conn_hash_flush+0xc7/0x220 net/bluetooth/hci_conn.c:1376
2 locks held by kworker/0:25/23979:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:26/23980:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:26/23981:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:27/23982:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:27/23983:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:28/23984:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:28/23985:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:29/23986:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:29/23987:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:30/23988:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:30/23990:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:31/23991:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:32/23992:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:31/23993:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:32/23995:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:33/23996:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:34/23997:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:33/23998:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:34/23999:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:35/24000:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:35/24001:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:36/24002:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:36/24003:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:37/24004:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:37/24005:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:38/24006:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:38/24007:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:39/24008:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:39/24009:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:40/24010:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:40/24011:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:41/24012:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:41/24013:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:42/24014:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:42/24015:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:43/24016:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:43/24017:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:44/24018:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:44/24019:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:45/24020:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:46/24021:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:45/24022:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:47/24023:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
3 locks held by kworker/0:48/24024:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
 #2:  (rcu_preempt_state.exp_mutex){+.+.}, at: [<ffffffff814d288d>] exp_funnel_lock kernel/rcu/tree_exp.h:305 [inline]
 #2:  (rcu_preempt_state.exp_mutex){+.+.}, at: [<ffffffff814d288d>] _synchronize_rcu_expedited+0x32d/0x770 kernel/rcu/tree_exp.h:596
2 locks held by kworker/1:46/24025:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:49/24026:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/1:47/24028:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:50/24029:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:51/24031:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091
2 locks held by kworker/0:52/24032:
 #0:  ("events"){+.+.}, at: [<ffffffff813ba640>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2087
 #1:  ((&ns->proc_work)){+.+.}, at: [<ffffffff813ba676>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2091

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

NMI backtrace for cpu 1
CPU: 1 PID: 1068 Comm: khungtaskd Not tainted 4.14.193-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x17f lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 6071 Comm: rs:main Q:Reg Not tainted 4.14.193-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88809737c380 task.stack: ffff8880957a8000
RIP: 0010:percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:47 [inline]
RIP: 0010:percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
RIP: 0010:__sb_start_write+0x1c6/0x2e0 fs/super.c:1363
RSP: 0018:ffff8880957afe10 EFLAGS: 00000a02
RAX: dffffc0000000000 RBX: ffff888094c96a80 RCX: ffffffff818d4d58
RDX: 1ffff110134e79b5 RSI: ffffffff86b30220 RDI: ffff88809a73cda8
RBP: ffff88809a73cd38 R08: ffffffff8a0880f8 R09: 00000000000503f6
R10: ffff88809737cc30 R11: ffff88809737c380 R12: ffff88809a73ca00
R13: 0000000000000001 R14: ffff88809a73cd38 R15: 0000000000000fe5
FS:  00007f91fcb1f700(0000) GS:ffff8880aea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c007f76008 CR3: 00000000a53a5000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 file_start_write include/linux/fs.h:2708 [inline]
 vfs_write+0x3d8/0x4d0 fs/read_write.c:543
 SYSC_write fs/read_write.c:590 [inline]
 SyS_write+0xf2/0x210 fs/read_write.c:582
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f91ff5631cd
RSP: 002b:00007f91fcb1e590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f91f4028800 RCX: 00007f91ff5631cd
RDX: 0000000000000fe5 RSI: 00007f91f4028800 RDI: 000000000000000a
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f91f4028580
R13: 00007f91fcb1e5b0 R14: 00005591860b07c0 R15: 0000000000000fe5
Code: 01 00 00 00 e8 0c f3 b0 ff 48 c7 c7 20 02 b3 86 e8 90 e3 77 01 48 8d 7d 70 59 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 ff 00 00 00 48 89 ef 48 8b 45 70 65 ff 00 e8 

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/08/11 18:35 linux-4.14.y 14b58326976d 5d3ebca9 .config log report