INFO: task bch-reclaim/loo:21239 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:bch-reclaim/loo state:D stack:18824 pid:21239 tgid:21239 ppid:2 task_flags:0x200040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115 __mutex_lock_common kernel/locking/mutex.c:676 [inline] __mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760 bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:773 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: #0: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 3 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/1:1/43: 3 locks held by kworker/u8:3/49: #0: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:644 #1: ffffc90000b97bc0 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000b97bc0 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff888055188250 (&devlink->lock_key#18){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb80 drivers/net/netdevsim/dev.c:853 3 locks held by kworker/u8:5/1083: 2 locks held by getty/5618: #0: ffff8880337e20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036c62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 6 locks held by syz-executor/19128: #0: ffff88807da420e0 (&type->s_umount_key#94){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807da420e0 (&type->s_umount_key#94){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807da420e0 (&type->s_umount_key#94){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffff888059c00278 (&c->state_lock){+.+.}-{4:4}, at: __bch2_fs_stop+0xf8/0x900 fs/bcachefs/super.c:676 #2: ffff888059c4af68 (&j->reclaim_lock){+.+.}-{4:4}, at: journal_flush_done+0x86/0x810 fs/bcachefs/journal_reclaim.c:884 #3: ffff888059c04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #3: ffff888059c04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #3: ffff888059c04398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7f4/0xd80 fs/bcachefs/btree_iter.c:3505 #4: ffff888059c04740 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x18bd/0x1a40 fs/bcachefs/btree_write_buffer.c:571 #5: ffff888059c26710 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 1 lock held by bch-reclaim/loo/21239: #0: ffff888059c4af68 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:773 2 locks held by syz.9.4308/22741: #0: ffffffff8f52c390 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566 #1: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 1 lock held by syz.7.4310/22745: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 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+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3fc/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: 0 Comm: swapper/1 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:82 Code: 3e 6d 96 f5 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 73 57 0e 00 f3 0f 1e fa fb f4 13 6d 96 f5 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffc90000197de0 EFLAGS: 000002c2 RAX: 47a5d300e55b7100 RBX: ffffffff819683f8 RCX: 47a5d300e55b7100 RDX: 0000000000000001 RSI: ffffffff8d9b8acb RDI: ffffffff8be33880 RBP: ffffc90000197f20 R08: ffff8880b8732f9b R09: 1ffff110170e65f3 R10: dffffc0000000000 R11: ffffed10170e65f4 R12: ffffffff8fa39630 R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110039d9b40 FS: 0000000000000000(0000) GS:ffff888125d18000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000002a9030 CR3: 0000000078aca000 CR4: 0000000000350ef0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline] default_idle+0x13/0x20 arch/x86/kernel/process.c:757 default_idle_call+0x74/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:190 [inline] do_idle+0x1e8/0x510 kernel/sched/idle.c:330 cpu_startup_entry+0x44/0x60 kernel/sched/idle.c:428 start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:315 common_startup_64+0x13e/0x147