INFO: task kworker/u8:12:7247 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:12 state:D stack:19160 pid:7247 tgid:7247 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: btree_node_rewrite async_btree_node_rewrite_work Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 __closure_sync+0x163/0x220 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:315 [inline] bch2_btree_update_start+0x18dc/0x1de0 fs/bcachefs/btree_update_interior.c:1293 bch2_btree_node_rewrite+0x17e/0x1120 fs/bcachefs/btree_update_interior.c:2246 bch2_btree_node_rewrite_key+0x273/0x320 fs/bcachefs/btree_update_interior.c:2312 async_btree_node_rewrite_work+0x110/0x4f0 fs/bcachefs/btree_update_interior.c:2369 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.3.3146:21923 blocked for more than 145 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.3146 state:D stack:19896 pid:21923 tgid:21921 ppid:21067 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5360 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964 __schedule_loop kernel/sched/core.c:7046 [inline] schedule+0x165/0x360 kernel/sched/core.c:7061 __closure_sync+0x163/0x220 lib/closure.c:146 bch2_wait_on_allocator fs/bcachefs/alloc_foreground.h:315 [inline] bch2_btree_update_start+0x18dc/0x1de0 fs/bcachefs/btree_update_interior.c:1293 bch2_btree_split_leaf+0x14b/0x8e0 fs/bcachefs/btree_update_interior.c:1921 bch2_trans_commit_error+0x1b7/0x1130 fs/bcachefs/btree_trans_commit.c:914 __bch2_trans_commit+0x1bb5/0x8880 fs/bcachefs/btree_trans_commit.c:1104 bch2_trans_commit fs/bcachefs/btree_update.h:241 [inline] bch2_journal_replay+0x1e85/0x2630 fs/bcachefs/recovery.c:440 bch2_run_recovery_pass fs/bcachefs/recovery_passes.c:484 [inline] __bch2_run_recovery_passes+0x3bd/0x1060 fs/bcachefs/recovery_passes.c:539 bch2_run_recovery_passes+0x184/0x210 fs/bcachefs/recovery_passes.c:610 bch2_fs_recovery+0x2690/0x3a50 fs/bcachefs/recovery.c:1016 bch2_fs_start+0xaaf/0xda0 fs/bcachefs/super.c:1213 bch2_fs_get_tree+0xb39/0x1520 fs/bcachefs/fs.c:2488 vfs_get_tree+0x92/0x2b0 fs/super.c:1751 fc_mount fs/namespace.c:1274 [inline] do_new_mount_fc fs/namespace.c:3726 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3802 do_mount fs/namespace.c:4125 [inline] __do_sys_mount fs/namespace.c:4324 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4301 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb35579034a RSP: 002b:00007fb35656ce68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fb35656cef0 RCX: 00007fb35579034a RDX: 00002000000058c0 RSI: 0000200000005900 RDI: 00007fb35656ceb0 RBP: 00002000000058c0 R08: 00007fb35656cef0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000005900 R13: 00007fb35656ceb0 R14: 000000000000590b R15: 00002000000002c0 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e33c820 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e33c820 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e33c820 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5627: #0: ffff88814d2fd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/u8:10/6649: #0: ffff88801b6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801b6fe948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90005567ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90005567ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f733bb0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: mpls_net_exit+0x79/0x270 net/mpls/af_mpls.c:2706 4 locks held by kworker/u8:12/7247: #0: ffff888028abf148 ((wq_completion)btree_node_rewrite){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888028abf148 ((wq_completion)btree_node_rewrite){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90003c6fba0 ((work_completion)(&a->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90003c6fba0 ((work_completion)(&a->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #2: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #2: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299 #3: ffff888095826710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 3 locks held by kworker/u8:14/14505: #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90003707ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90003707ba0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 2 locks held by syz.3.3146/21923: #0: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299 #1: ffff888095826710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 4 locks held by bch-reclaim/loo/21976: #0: ffff88809584af68 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:773 #1: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #1: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #1: ffff888095804398 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7f4/0xd80 fs/bcachefs/btree_iter.c:3505 #2: ffff888095804740 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x18bd/0x1a40 fs/bcachefs/btree_write_buffer.c:571 #3: ffff888095826710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 1 lock held by syz-executor/23525: #0: ffffffff8e3422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8e3422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 3 locks held by syz-executor/24471: #0: ffffffff8eeafb60 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8eeafb60 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8eeafb60 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 #2: ffffffff8e3422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #2: ffffffff8e3422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 ============================================= 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 08/18/2025 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:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 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: 4611 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline] RIP: 0010:check_preemption_disabled+0x59/0x120 lib/smp_processor_id.c:19 Code: 8b 0d 9b 64 40 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9 c1 ce 02 00 cc 48 c7 04 24 00 00 00 00 9c <8f> 04 24 f7 04 24 00 02 00 00 74 c8 65 4c 8b 3c 25 08 80 c3 92 41 RSP: 0018:ffffc9000dfa7920 EFLAGS: 00000046 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000000 RDX: 0000000000000000 RSI: ffffffff8dbd2232 RDI: ffffffff8c036f00 RBP: ffffffff8b509a82 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8b5099b0 R12: 0000000000000002 R13: ffffffff8e33c820 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff888125ae8000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555587e3b5c8 CR3: 000000000e138000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000006800 DR2: 0000000000009951 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline] lock_acquire+0xe7/0x360 kernel/locking/lockdep.c:5867 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xef/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245