INFO: task kworker/u4:2:33 blocked for more than 143 seconds. Not tainted 6.1.96-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:23992 pid:33 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747 jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102 jfs_write_inode+0x13f/0x210 fs/jfs/inode.c:132 write_inode fs/fs-writeback.c:1460 [inline] __writeback_single_inode+0x67d/0x11e0 fs/fs-writeback.c:1677 writeback_sb_inodes+0xc2b/0x1b20 fs/fs-writeback.c:1903 __writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:1974 wb_writeback+0x4b1/0xe10 fs/fs-writeback.c:2079 wb_check_background_flush fs/fs-writeback.c:2145 [inline] wb_do_writeback fs/fs-writeback.c:2233 [inline] wb_workfn+0xc9e/0x1020 fs/fs-writeback.c:2260 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Showing all locks held in the system: 6 locks held by kworker/u4:0/9: #0: ffff888012616938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900000e7d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e28da10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:566 #3: ffffffff8d1302b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #3: ffffffff8d1302b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 #4: ffff8880b993aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #5: ffff8880b9927788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x43d/0x770 kernel/sched/psi.c:1000 2 locks held by kworker/u4:1/11: #0: ffff8880b993aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #1: ffff8880b9927788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x43d/0x770 kernel/sched/psi.c:1000 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d12ae90 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d12b690 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/27: #0: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d12acc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 4 locks held by kworker/u4:2/33: #0: ffff888145259138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90000aa7d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff88805d29c0e0 (&type->s_umount_key#74){.+.+}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88805c6ab008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102 5 locks held by kworker/0:2/153: #0: ffff888143ac2d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90002d5fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888022f37190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:837 [inline] #2: ffff888022f37190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1fe/0x5730 drivers/usb/core/hub.c:5801 #3: ffff888022f434f8 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3159 [inline] #3: ffff888022f434f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5373 [inline] #3: ffff888022f434f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5617 [inline] #3: ffff888022f434f8 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5773 [inline] #3: ffff888022f434f8 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x2471/0x5730 drivers/usb/core/hub.c:5855 #4: ffff8880217e1a68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5374 [inline] #4: ffff8880217e1a68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5617 [inline] #4: ffff8880217e1a68 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5773 [inline] #4: ffff8880217e1a68 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x249e/0x5730 drivers/usb/core/hub.c:5855 2 locks held by getty/3302: #0: ffff88814baba098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 2 locks held by kworker/1:3/3550: #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000404fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by kworker/1:6/3596: #0: ffff888012472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900042cfd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 2 locks held by kworker/u4:8/4208: 4 locks held by syz.3.273/4451: 2 locks held by kworker/1:14/5038: #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc9000332fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 1 lock held by syz.1.444/5090: #0: ffff88814c610460 (sb_writers#4){.+.+}-{0:0}, at: do_coredump+0x1892/0x2700 fs/coredump.c:754 4 locks held by kworker/u4:12/5238: 3 locks held by kworker/0:14/5340: #0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc900051d7d20 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8d1302b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #2: ffffffff8d1302b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.2.793/6178: 1 lock held by syz.4.811/6229: #0: ffff88814c610460 (sb_writers#4){.+.+}-{0:0}, at: do_coredump+0x1892/0x2700 fs/coredump.c:754 1 lock held by syz.4.844/6346: #0: ffff88814c610460 (sb_writers#4){.+.+}-{0:0}, at: do_coredump+0x1892/0x2700 fs/coredump.c:754 4 locks held by syz.4.864/6401: #0: ffff88814c610460 (sb_writers#4){.+.+}-{0:0}, at: do_coredump+0x1892/0x2700 fs/coredump.c:754 #1: ffff8880b993aa18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537 #2: ffff8880b9927788 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x43d/0x770 kernel/sched/psi.c:1000 #3: ffff888142b0d088 (&virtscsi_vq->vq_lock){-.-.}-{2:2}, at: virtscsi_add_cmd+0xb1/0x6d0 drivers/scsi/virtio_scsi.c:492 1 lock held by syz.3.884/6473: #0: ffff88814c610460 (sb_writers#4){.+.+}-{0:0}, at: do_coredump+0x1892/0x2700 fs/coredump.c:754 1 lock held by syz.3.902/6533: #0: ffff88814c610460 (sb_writers#4){.+.+}-{0:0}, at: do_coredump+0x1892/0x2700 fs/coredump.c:754 1 lock held by syz.2.923/6596: #0: ffff88801fb33b60 (&lo->lo_mutex){+.+.}-{3:3}, at: loop_set_status+0x2a/0x910 drivers/block/loop.c:1267 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 6.1.96-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.96-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:__local_bh_enable_ip+0x11f/0x1f0 Code: fa a9 00 02 00 00 74 05 e8 2e 3a 3d 00 65 8b 05 df 4f ae 7e 25 00 ff 00 00 3d 00 02 00 00 75 0a 48 8b 7c 24 18 e8 01 16 16 00 01 00 00 00 44 29 f8 65 01 05 ba 4f ae 7e 65 8b 05 b3 4f ae 7e RSP: 0018:ffffc90000107aa0 EFLAGS: 00000046 RAX: 2300443bb9ec7700 RBX: 1ffff92000020f58 RCX: ffffffff91c94103 RDX: dffffc0000000000 RSI: ffffffff8aec13c0 RDI: ffffffff8b3d4760 RBP: ffffc90000107b50 R08: dffffc0000000000 R09: ffffed100c3b5049 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000020f5c R14: ffffc90000107ae0 R15: 0000000000000201 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd187ad0ab8 CR3: 000000000ce8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x30e/0x3b0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x361/0x610 net/batman-adv/network-coding.c:722 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308