INFO: task kworker/u9:2:83 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u9:2    state:D stack:20616 pid:83    tgid:83    ppid:2      task_flags:0x4248060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-bcachefs-177)
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 __closure_sync_timeout+0x282/0x3a0
 __bch2_wait_on_allocator+0x112/0x240
 __bch2_write+0x31ef/0x3900
 __bch2_writepage+0x1536/0x2790
 write_cache_pages+0x64/0x100
 bch2_writepages+0xf9/0x2d0
 do_writepages+0x32e/0x550
 __writeback_single_inode+0x145/0xff0
 writeback_sb_inodes+0x6c7/0x1010
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x44f/0xaf0
 wb_workfn+0xaef/0xef0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task kworker/u10:6:1094 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u10:6   state:D stack:19640 pid:1094  tgid:1094  ppid:2      task_flags:0x4248060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-bcachefs-268)
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 __closure_sync_timeout+0x282/0x3a0
 __bch2_wait_on_allocator+0x112/0x240
 __bch2_write+0x31ef/0x3900
 __bch2_writepage+0x1536/0x2790
 write_cache_pages+0x64/0x100
 bch2_writepages+0xf9/0x2d0
 do_writepages+0x32e/0x550
 __writeback_single_inode+0x145/0xff0
 writeback_sb_inodes+0x6c7/0x1010
 __writeback_inodes_wb+0x111/0x240
 wb_writeback+0x44f/0xaf0
 wb_workfn+0xaef/0xef0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
INFO: task syz.3.759:10577 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.759       state:D stack:17424 pid:10577 tgid:10556 ppid:7026   task_flags:0x440040 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 __closure_sync_timeout+0x282/0x3a0
 __bch2_wait_on_allocator+0x112/0x240
 __bch2_write+0x31ef/0x3900
 __bch2_writepage+0x1536/0x2790
 write_cache_pages+0x64/0x100
 bch2_writepages+0xf9/0x2d0
 do_writepages+0x32e/0x550
 file_write_and_wait_range+0x23e/0x340
 bch2_fsync+0x127/0x330
 bch2_write_iter+0x2822/0x2b90
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3392f8ec29
RSP: 002b:00007f3393ed2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f33931d6090 RCX: 00007f3392f8ec29
RDX: 000000000208e24b RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007f3393011e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f33931d6128 R14: 00007f33931d6090 R15: 00007fffe92638f8
 </TASK>
INFO: task syz.2.1314:13474 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1314      state:D stack:18696 pid:13474 tgid:13435 ppid:13166  task_flags:0x440040 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 __closure_sync_timeout+0x282/0x3a0
 __bch2_wait_on_allocator+0x112/0x240
 __bch2_write+0x31ef/0x3900
 __bch2_writepage+0x1536/0x2790
 write_cache_pages+0x64/0x100
 bch2_writepages+0xf9/0x2d0
 do_writepages+0x32e/0x550
 file_write_and_wait_range+0x23e/0x340
 bch2_fsync+0x127/0x330
 bch2_write_iter+0x2822/0x2b90
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f595cf8ec29
RSP: 002b:00007f595dd40038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f595d1d6090 RCX: 00007f595cf8ec29
RDX: 000000000208e24b RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007f595d011e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f595d1d6128 R14: 00007f595d1d6090 R15: 00007fff44bfa278
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e13a0e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/u9:2/83:
 #0: ffff88801b397148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000178fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff888126dd40e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
3 locks held by kworker/u10:6/1094:
 #0: ffff88801b397148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90006e87bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff8880236900e0 (&type->s_umount_key#53){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
2 locks held by getty/5677:
 #0: ffff888027dd10a0 (&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
2 locks held by syz.3.759/10577:
 #0: ffff88810a87bef8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320
 #1: ffff888126dd4428 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
2 locks held by syz.2.1314/13474:
 #0: ffff88810f8c48f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320
 #1: ffff888023690428 (sb_writers#13){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
3 locks held by syz.7.2705/19358:

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

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+0x439/0x7d0
 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: 19358 Comm: syz.7.2705 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:dequeue_dl_entity+0x748/0xa80
Code: 55 8b 00 49 8b 1f 48 b8 00 00 00 00 00 fc ff df 41 80 7c 05 00 00 74 08 4c 89 f7 e8 02 55 8b 00 49 3b 1e 44 8b 6c 24 08 77 4c <41> f6 c5 01 75 50 48 83 c4 38 5b 41 5c 41 5d 41 5e 41 5f 5d e9 ff
RSP: 0018:ffffc9000320e7e8 EFLAGS: 00000046
RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: dffffc0000000000
RDX: 1ffff11026cc7538 RSI: 0000000000000000 RDI: ffff88813663a970
RBP: ffff88813663a970 R08: ffffffff8fa3a737 R09: 1ffffffff1f474e6
R10: dffffc0000000000 R11: fffffbfff1f474e7 R12: ffff888136639f80
R13: 0000000000000000 R14: ffff88813663a9c4 R15: 1ffff11026cc7538
FS:  00007f0f8e5ee6c0(0000) GS:ffff8881a3c13000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000020000001a000 CR3: 0000000026c42000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 update_curr_dl_se+0x48e/0x990
 update_curr+0x3fb/0x730
 put_prev_entity+0x41/0x230
 put_prev_task_fair+0x4b/0x80
 put_prev_set_next_task+0x10a/0x180
 __pick_next_task+0x3eb/0x450
 __schedule+0x7a4/0x4cc0
 preempt_schedule_irq+0xb5/0x150
 irqentry_exit+0x6f/0x90
 asm_sysvec_call_function_single+0x1a/0x20
RIP: 0010:unwind_next_frame+0x4eb/0x2390
Code: 72 04 4c 8d 62 05 48 89 f0 48 c1 e8 03 48 89 44 24 40 0f b6 04 28 84 c0 48 89 54 24 08 48 89 34 24 0f 85 4d 18 00 00 4c 89 e0 <48> c1 e8 03 0f b6 04 28 84 c0 0f 85 63 18 00 00 0f b7 1e c1 eb 0b
RSP: 0018:ffffc9000320edb8 EFLAGS: 00000246
RAX: ffffffff90342f9f RBX: ffffffff8fb7f3a8 RCX: ffffffff8fb7f3ac
RDX: ffffffff90342f9a RSI: ffffffff90342f9e RDI: ffffffff8be33f20
RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8172c195
R10: ffffc9000320eed8 R11: ffffffff81ac3b00 R12: ffffffff90342f9f
R13: ffffc9000320eed8 R14: ffffc9000320ee88 R15: ffffffff8172c195
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 save_stack+0xf5/0x1f0
 __reset_page_owner+0x71/0x1f0
 free_unref_folios+0xdbd/0x1520
 folios_put_refs+0x559/0x640
 shmem_undo_range+0x49e/0x14b0
 shmem_evict_inode+0x272/0xa70
 evict+0x504/0x9c0
 __dentry_kill+0x209/0x660
 dput+0x19f/0x2b0
 __fput+0x68e/0xa70
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 irqentry_exit_to_user_mode+0x81/0x120
 exc_debug_user+0xda/0x110
 asm_exc_debug+0x33/0x40
RIP: 0033:0x7f0f9038ec2f
Code: Unable to access opcode bytes at 0x7f0f9038ec05.
RSP: 002b:00007f0f8e5edfe8 EFLAGS: 00000317
RAX: 0000000000000000 RBX: 00007f0f905d5fa0 RCX: 00007f0f9038ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f0f90411e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0f905d6038 R14: 00007f0f905d5fa0 R15: 00007ffc284220a8
 </TASK>
