INFO: task kworker/u8:16:4184 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:16 state:D stack:23816 pid:4184 tgid:4184 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: btree_node_rewrite async_btree_node_rewrite_work Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 __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:3236 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 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 INFO: task syz.4.8:5986 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.8 state:D stack:19320 pid:5986 tgid:5983 ppid:5842 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 __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+0x1bb5/0x8870 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:1815 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808 do_mount fs/namespace.c:4136 [inline] __do_sys_mount fs/namespace.c:4347 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4324 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd00607038a RSP: 002b:00007fd004293e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007fd004293ef0 RCX: 00007fd00607038a RDX: 00002000000000c0 RSI: 0000200000000040 RDI: 00007fd004293eb0 RBP: 00002000000000c0 R08: 00007fd004293ef0 R09: 0000000000808040 R10: 0000000000808040 R11: 0000000000000246 R12: 0000200000000040 R13: 00007fd004293eb0 R14: 0000000000005904 R15: 0000200000000100 INFO: task bch-reclaim/loo:6008 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:23944 pid:6008 tgid:6008 ppid:2 task_flags:0x200840 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5357 [inline] __schedule+0x16f3/0x4c20 kernel/sched/core.c:6961 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0x165/0x360 kernel/sched/core.c:7058 __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+0x1bb5/0x8870 fs/bcachefs/btree_trans_commit.c:1104 bch2_trans_commit fs/bcachefs/btree_update.h:241 [inline] bch2_btree_write_buffer_flush_locked+0x451f/0x4dd0 fs/bcachefs/btree_write_buffer.c:454 btree_write_buffer_flush_seq+0x18c7/0x1a40 fs/bcachefs/btree_write_buffer.c:572 bch2_btree_write_buffer_journal_flush+0x69/0xb0 fs/bcachefs/btree_write_buffer.c:588 journal_flush_pins+0x8e3/0xe90 fs/bcachefs/journal_reclaim.c:604 __bch2_journal_reclaim+0x910/0xed0 fs/bcachefs/journal_reclaim.c:732 bch2_journal_reclaim_thread+0x177/0x4f0 fs/bcachefs/journal_reclaim.c:774 kthread+0x711/0x8a0 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 Showing all locks held in the system: 4 locks held by kworker/u8:0/12: 3 locks held by kworker/u8:1/13: #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90000127bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000127bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 4 locks held by pr/legacy/17: 1 lock held by khungtaskd/38: #0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by jfsCommit/121: #0: ffff88805cfe0900 (&(imap->im_aglock[index])){+.+.}-{4:4}, at: diFree+0x29b/0x2c30 fs/jfs/jfs_imap.c:889 #1: ffff88805c1d0168 (&jfs_ip->rdwrlock/1){++++}-{4:4}, at: diFree+0x2b9/0x2c30 fs/jfs/jfs_imap.c:894 4 locks held by kworker/u8:5/190: #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc90003ba7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90003ba7bc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffffffff8ecc5400 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658 #3: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12719 6 locks held by kworker/u8:7/1013: 2 locks held by kworker/u8:13/3587: 3 locks held by kworker/u8:14/3611: 4 locks held by kworker/u8:16/4184: #0: ffff888060ae1138 ((wq_completion)btree_node_rewrite){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888060ae1138 ((wq_completion)btree_node_rewrite){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319 #1: ffffc9000ec3fbc0 ((work_completion)(&a->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000ec3fbc0 ((work_completion)(&a->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319 #2: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #2: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #2: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299 #3: ffff888060937360 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 2 locks held by udevd/5211: 2 locks held by dhcpcd/5506: #0: ffff88805bc94908 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xbd/0xe90 net/netlink/af_netlink.c:2269 #1: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6814 2 locks held by getty/5602: #0: ffff88823bf688a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5851: #0: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline] #0: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x41/0x1c0 drivers/net/tun.c:3433 2 locks held by syz.4.8/5986: #0: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #0: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #0: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3299 #1: ffff888060937360 (&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/6008: #0: ffff88806096ce18 (&j->reclaim_lock){+.+.}-{4:4}, at: bch2_journal_reclaim_thread+0x16b/0x4f0 fs/bcachefs/journal_reclaim.c:773 #1: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline] #1: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline] #1: ffff888060904678 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7f3/0xd80 fs/bcachefs/btree_iter.c:3505 #2: ffff888060904a30 (&wb->flushing.lock){+.+.}-{4:4}, at: btree_write_buffer_flush_seq+0x18bd/0x1a40 fs/bcachefs/btree_write_buffer.c:571 #3: ffff888060937360 (&c->gc_lock){.+.+}-{4:4}, at: bch2_btree_update_start+0x542/0x1de0 fs/bcachefs/btree_update_interior.c:1211 1 lock held by syz.0.110/6783: 1 lock held by udevd/6969: #0: ffff8880222988a8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #0: ffff8880222988a8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_llseek+0x6d/0xc0 block/fops.c:603 3 locks held by udevd/7124: 2 locks held by syz-executor/7581: #0: ffffffff8e43ac60 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e43ac60 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e43ac60 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8ecd22f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056 1 lock held by syz.5.202/7777: 4 locks held by syz.7.201/7782: #0: ffff8880712340d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x204/0x990 fs/super.c:345 #1: ffff8880222988a8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline] #1: ffff8880222988a8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: set_blocksize+0x23b/0x450 block/bdev.c:203 #2: ffff888022298a78 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:924 [inline] #2: ffff888022298a78 (mapping.invalidate_lock){++++}-{4:4}, at: set_blocksize+0x26c/0x450 block/bdev.c:204 #3: ffff88813fffc5d8 (&zone->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline] #3: ffff88813fffc5d8 (&zone->lock){+.+.}-{3:3}, at: free_one_page+0x41/0x270 mm/page_alloc.c:1542 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(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+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: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400 Code: e8 de ae 7f fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 9f e5 de 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:ffffc90000167890 EFLAGS: 00000202 RAX: 1ffffffff3275000 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff993a8850 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff853eafa0 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff993a85c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881269c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000080 CR3: 0000000049bfc000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1984 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3288 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3311 [inline] serial8250_console_write+0x11bd/0x1b40 drivers/tty/serial/8250/8250_port.c:3396 console_emit_next_record kernel/printk/printk.c:3118 [inline] console_flush_all+0x695/0xcd0 kernel/printk/printk.c:3226 __console_flush_and_unlock+0xa4/0x240 kernel/printk/printk.c:3285 legacy_kthread_func+0x13b/0x1a0 kernel/printk/printk.c:3638 kthread+0x711/0x8a0 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