INFO: task kworker/u9:4:1090 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u9:4    state:D stack:22600 pid:1090  tgid:1090  ppid:2      task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:8)
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 jfs_commit_inode+0x1ca/0x530
 jfs_write_inode+0x145/0x220
 __writeback_single_inode+0x6f1/0xff0
 writeback_sb_inodes+0x6c7/0x1010
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x44f/0xaf0
 wb_workfn+0x90b/0xef0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz.8.331:8468 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.331       state:D stack:28936 pid:8468  tgid:8462  ppid:7625   task_flags:0x400040 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 wb_wait_for_completion+0x15f/0x260
 sync_inodes_sb+0x1bb/0xa10
 __iterate_supers+0x13d/0x290
 ksys_sync+0x94/0x150
 __ia32_sys_sync+0xe/0x20
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff0ad18ebe9
RSP: 002b:00007ff0ae057038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007ff0ad3c6090 RCX: 00007ff0ad18ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ff0ad3c6090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0ad3c6128 R14: 00007ff0ad3c6090 R15: 00007fffcaf05388
 </TASK>
INFO: task syz.8.331:8469 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.331       state:D stack:28936 pid:8469  tgid:8462  ppid:7625   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write_nested+0x1b5/0x200
 filename_create+0x1f8/0x3c0
 do_mkdirat+0xa0/0x590
 __x64_sys_mkdirat+0x87/0xa0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff0ad18d457
RSP: 002b:00007ff0ae035e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007ff0ae035ef0 RCX: 00007ff0ad18d457
RDX: 00000000000001ff RSI: 0000200000021700 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000021700
R13: 00007ff0ae035eb0 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
INFO: task syz.8.331:8470 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.331       state:D stack:28936 pid:8470  tgid:8462  ppid:7625   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 lookup_slow+0x46/0x70
 walk_component+0x2d2/0x400
 path_lookupat+0x163/0x430
 filename_lookup+0x212/0x570
 do_linkat+0x120/0x560
 __x64_sys_link+0x82/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff0ad18ebe9
RSP: 002b:00007ff0ae015038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056
RAX: ffffffffffffffda RBX: 00007ff0ad3c6270 RCX: 00007ff0ad18ebe9
RDX: 0000000000000000 RSI: 0000200000000300 RDI: 0000200000000000
RBP: 00007ff0ad211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0ad3c6308 R14: 00007ff0ad3c6270 R15: 00007fffcaf05388
 </TASK>
INFO: task syz.8.331:8471 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.331       state:D stack:28936 pid:8471  tgid:8462  ppid:7625   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x872/0xfe0
 down_write_nested+0x1b5/0x200
 filename_create+0x1f8/0x3c0
 do_mkdirat+0xa0/0x590
 __x64_sys_mkdir+0x6c/0x80
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff0ad18ebe9
RSP: 002b:00007ff0adff4038 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007ff0ad3c6360 RCX: 00007ff0ad18ebe9
RDX: 0000000000000000 RSI: 0000000000000010 RDI: 0000200000000540
RBP: 00007ff0ad211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0ad3c63f8 R14: 00007ff0ad3c6360 R15: 00007fffcaf05388
 </TASK>

Showing all locks held in the system:
3 locks held by ksoftirqd/1/23:
3 locks held by kworker/1:0/24:
 #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900001c7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff888028f81240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180
3 locks held by kworker/u9:1/32:
 #0: ffff888136639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140
 #1: ffff888136624008 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880
 #2: ffff888136625918 (&base->lock){-.-.}-{2:2}, at: __mod_timer+0x8ee/0xf30
1 lock held by khungtaskd/34:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u9:4/1090:
 #0: ffff888100197148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90006d67bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff888114e1a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
 #3: ffff888112f5ddf8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530
2 locks held by getty/5676:
 #0: ffff888024dd50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
4 locks held by syz.8.331/8463:
2 locks held by syz.8.331/8468:
 #0: ffff888114e1a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
 #1: ffff8880212a07d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10
2 locks held by syz.8.331/8469:
 #0: ffff888114e1a428 (sb_writers#24){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888112f5e1a8 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
1 lock held by syz.8.331/8470:
 #0: ffff888112f5e1a8 (&type->i_mutex_dir_key#18){++++}-{4:4}, at: lookup_slow+0x46/0x70
2 locks held by syz.8.331/8471:
 #0: ffff888114e1a428 (sb_writers#24){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90
 #1: ffff888112f5e1a8 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0
2 locks held by syz-executor/8756:
 #0: ffff88803c3940e0 (&type->s_umount_key#57){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8e13f880 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570
1 lock held by syz-executor/10276:
 #0: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 10949 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70
Code: 89 fb e8 23 00 00 00 48 8b 3d 14 76 fe 0b 48 89 de 5b e9 83 b5 58 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 b0 a0 92 65 8b 15 38 01
RSP: 0018:ffffc900035bf398 EFLAGS: 00000246
RAX: 0000000000000003 RBX: ffff88802817a080 RCX: 0000000000000005
RDX: ffffffff8b731c22 RSI: ffffffff8f8a6ca0 RDI: 0000000000000001
RBP: ffffc900035bf570 R08: ffff88810a94b980 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000000 R12: ffff888116f6f980
R13: dffffc0000000000 R14: ffff888115e3d400 R15: 0000000000000001
FS:  0000000000000000(0000) GS:ffff8881a3c15000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f195d58a3b0 CR3: 000000010773e000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 mt_validate+0x3efb/0x4380
 validate_mm+0xb6/0x4b0
 vms_complete_munmap_vmas+0x6aa/0x8a0
 mmap_region+0x11db/0x20c0
 do_mmap+0xc45/0x10d0
 vm_mmap_pgoff+0x2a6/0x4d0
 ksys_mmap_pgoff+0x51f/0x760
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f195d805b74
Code: 63 08 44 89 e8 5b 41 5c 41 5d c3 41 89 ca 41 f7 c1 ff 0f 00 00 74 0c c7 05 f5 46 01 00 16 00 00 00 eb 17 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 0c f7 d8 89 05 dc 46 01 00 48 83 c8 ff c3 0f
RSP: 002b:00007ffee23729f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007ffee2372a70 RCX: 00007f195d805b74
RDX: 0000000000000001 RSI: 0000000000003000 RDI: 00007f195d565000
RBP: 00007ffee2372dd0 R08: 0000000000000003 R09: 0000000000009000
R10: 0000000000000812 R11: 0000000000000246 R12: 00007f195d7e0a00
R13: 00007ffee2372e58 R14: 0000000000008442 R15: 0000000000000000
 </TASK>
