INFO: task syz-executor:5855 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21800 pid:5855 tgid:5855 ppid:1 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5351 [inline] __schedule+0x1737/0x4d30 kernel/sched/core.c:6954 __schedule_loop kernel/sched/core.c:7036 [inline] schedule+0x165/0x360 kernel/sched/core.c:7051 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+0x194/0x5c0 kernel/kthread.c:790 bch2_copygc_stop+0x4b/0x120 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+0x1d4/0x260 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: 0033:0x7f7fa278fcd7 RSP: 002b:00007ffec59c9678 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f7fa2810b55 RCX: 00007f7fa278fcd7 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffec59c9730 RBP: 00007ffec59c9730 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffec59ca7c0 R13: 00007f7fa2810b55 R14: 00000000000186d2 R15: 00007ffec59ca800 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5605: #0: ffff8880303ce0a0 (&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 3 locks held by udevd/5847: 7 locks held by kworker/u9:5/5853: 2 locks held by syz-executor/5855: #0: ffff8880558120e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880558120e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880558120e0 (&type->s_umount_key#63){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888057700278 (&c->state_lock){++++}-{4:4}, at: class_rwsem_write_constructor include/linux/rwsem.h:257 [inline] #1: ffff888057700278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xc1/0x8f0 fs/bcachefs/super.c:699 3 locks held by kworker/0:4/5946: #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc900047b7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc900047b7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff88805c2a5240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x26b/0x3180 drivers/net/netdevsim/fib.c:1490 2 locks held by bch-copygc/loop/6072: #0: ffff8880577043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffff8880577043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffff8880577043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3293 #1: ffff888057726710 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x53f/0x1e00 fs/bcachefs/btree_update_interior.c:1196 1 lock held by syz.4.64/6342: #0: ffff8880558120e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline] #0: ffff8880558120e0 (&type->s_umount_key#63){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121 1 lock held by syz-executor/6590: 3 locks held by kworker/u8:10/6705: #0: ffff88801b2fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b2fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000b467bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000b467bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8f519070 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 2 locks held by kworker/u8:13/7737: 2 locks held by syz.0.359/8251: 2 locks held by syz.1.361/8255: 2 locks held by syz-executor/8261: #0: ffffffff8f519070 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566 #1: ffffffff8e143338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e143338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:967 2 locks held by syz.7.362/8266: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-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+0xf93/0xfe0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5203 Comm: klogd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0033:0x7f4694357390 Code: f5 48 8b 7f 08 eb 2d 0f 1f 00 48 29 fb 4c 89 ee 48 39 eb 48 0f 47 dd 48 89 da 49 01 dd e8 28 1f fd ff 49 8b 7c 24 08 48 01 df <49> 89 7c 24 08 48 29 dd 74 46 49 8b 5c 24 10 48 39 fb 75 cc 4c 89 RSP: 002b:00007fff01da8e50 EFLAGS: 00000202 RAX: 00007fff01da9643 RBX: 0000000000000006 RCX: 000000006c656e72 RDX: 0000000000000006 RSI: 000000006e72656b RDI: 00007fff01da9649 RBP: 0000000000000006 R08: 0000000000000073 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: 00007fff01da9380 R13: 00007f4694580a42 R14: 00000000fffffffa R15: 0000000000000000 FS: 00007f4694238c80 GS: 0000000000000000