INFO: task syz-executor:9372 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-next-20250717-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:18984 pid:9372 tgid:9372 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5314 [inline]
__schedule+0x16fd/0x4cf0 kernel/sched/core.c:6697
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
kthread_stop+0x194/0x5f0 kernel/kthread.c:790
bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:436
__bch2_fs_read_only+0x4a/0x4f0 fs/bcachefs/super.c:303
bch2_fs_read_only+0x403/0xa40 fs/bcachefs/super.c:389
__bch2_fs_stop+0xc9/0x8f0 fs/bcachefs/super.c:700
generic_shutdown_super+0x132/0x2c0 fs/super.c:643
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2586
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1fc818fc57
RSP: 002b:00007fff30dbb578 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f1fc8210a8d RCX: 00007f1fc818fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff30dbb630
RBP: 00007fff30dbb630 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff30dbc6c0
R13: 00007f1fc8210a8d R14: 00000000000aaaa2 R15: 00007fff30dbc700
Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
#0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
#1: ffff8880b8624008 (per_cpu_ptr(&psi_seq, cpu)){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:937
1 lock held by khungtaskd/31:
#0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5605:
#0: ffff88814dba60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/9372:
#0: ffff8880487080e0 (&type->s_umount_key#53){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff8880487080e0 (&type->s_umount_key#53){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff8880487080e0 (&type->s_umount_key#53){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888092d00278 (&c->state_lock){++++}-{4:4}, at: class_rwsem_write_constructor include/linux/rwsem.h:257 [inline]
#1: ffff888092d00278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xc1/0x8f0 fs/bcachefs/super.c:699
1 lock held by syz-executor/12871:
#0: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
3 locks held by kworker/u8:20/15906:
#0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
#1: ffffc9000b6afbc0 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000b6afbc0 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
2 locks held by bch-copygc/loop/21449:
#0: ffff888092d043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#0: ffff888092d043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#0: ffff888092d043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3293
#1: ffff888092d26710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x53f/0x1e00 fs/bcachefs/btree_update_interior.c:1196
1 lock held by syz-executor/21720:
#0: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250717-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted 6.16.0-rc6-next-20250717-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: writeback wb_workfn (flush-7:5)
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 de d1 6f fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 df 98 d4 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000116558 EFLAGS: 00000006
RAX: 1ffffffff33c8105 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffc90000116730 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff854fff30 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff99e409a0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125bd9000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa92eb82ab8 CR3: 000000003a510000 CR4: 00000000003526f0
Call Trace:
serial_port_in include/linux/serial_core.h:793 [inline]
serial8250_console_write+0x584/0x1ba0 drivers/tty/serial/8250/8250_port.c:3360
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x725/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
_printk+0xcf/0x120 kernel/printk/printk.c:2475
bio_check_eod block/blk-core.c:563 [inline]
submit_bio_noacct+0x108b/0x1a70 block/blk-core.c:796
__submit_merged_bio+0x27a/0x6a0 fs/f2fs/data.c:540
__f2fs_submit_merged_write fs/f2fs/data.c:635 [inline]
__submit_merged_write_cond+0x255/0x530 fs/f2fs/data.c:657
f2fs_submit_merged_write_cond fs/f2fs/data.c:674 [inline]
f2fs_write_cache_pages fs/f2fs/data.c:3205 [inline]
__f2fs_write_data_pages fs/f2fs/data.c:3286 [inline]
f2fs_write_data_pages+0x261d/0x3000 fs/f2fs/data.c:3313
do_writepages+0x32e/0x550 mm/page-writeback.c:2634
__writeback_single_inode+0x145/0xff0 fs/fs-writeback.c:1680
writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976
wb_writeback+0x43b/0xaf0 fs/fs-writeback.c:2156
wb_do_writeback fs/fs-writeback.c:2303 [inline]
wb_workfn+0x409/0xef0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245