INFO: task kworker/u4:8:4484 blocked for more than 143 seconds. Not tainted 6.1.106-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:8 state:D stack:21208 pid:4484 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:4) Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 f2fs_write_inode+0x4c3/0x540 fs/f2fs/inode.c:739 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_old_data_flush fs/fs-writeback.c:2179 [inline] wb_do_writeback fs/fs-writeback.c:2232 [inline] wb_workfn+0xbec/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:295 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b190 (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: ffffffff8d32b990 (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/28: #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32afc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494 4 locks held by kworker/u4:4/57: #0: ffff888012a1e938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90001587d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffffffff8e4ec550 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:566 #3: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit_batch+0x1c/0x90 net/can/gw.c:1250 2 locks held by getty/3395: #0: ffff88814b80a098 (&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/1:11/3864: #0: ffff888012872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90004e07d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 4 locks held by kworker/u4:7/4080: #0: ffff888014e47938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90005357d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff88802406a0e0 (&type->s_umount_key#65){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff88805c273948 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102 5 locks held by syz.4.159/4266: 4 locks held by kworker/u4:8/4484: #0: ffff888014e47938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #1: ffffc90003bdfd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267 #2: ffff888076bac0e0 (&type->s_umount_key#73){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:415 #3: ffff8880794e9140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2176 [inline] #3: ffff8880794e9140 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x4fb/0x6c0 fs/f2fs/segment.c:428 2 locks held by syz.2.379/5901: #0: ffff888076bac0e0 (&type->s_umount_key#73){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 #1: ffff8881437907d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] #1: ffff8881437907d0 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x270/0xb10 fs/fs-writeback.c:2737 4 locks held by syz.0.580/6316: 2 locks held by syz.3.811/7118: #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3492 #1: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #1: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.0.812/7122: #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0x51d/0x3bb0 net/ipv4/ip_sockglue.c:954 1 lock held by syz.0.812/7123: #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118 1 lock held by syz.0.812/7124: #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118 1 lock held by syz.0.812/7125: #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118 1 lock held by syz.0.812/7128: #0: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: do_ip_setsockopt+0x51d/0x3bb0 net/ipv4/ip_sockglue.c:954 3 locks held by syz.1.823/7151: #0: ffff8880518661c0 (&tty->legacy_mutex){+.+.}-{3:3}, at: tty_set_ldisc+0x4e/0x560 drivers/tty/tty_ldisc.c:529 #1: ffff888051866098 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:290 [inline] #1: ffff888051866098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock+0x68/0xb0 drivers/tty/tty_ldisc.c:314 #2: ffffffff8e4f88a8 (rtnl_mutex){+.+.}-{3:3}, at: slip_open+0xd6/0xe70 drivers/net/slip/slip.c:803 1 lock held by syz.1.823/7152: #0: ffff888051866098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 1 lock held by syz.4.826/7163: #0: ffff888076bac0e0 (&type->s_umount_key#73){++++}-{3:3}, at: get_super+0xfe/0x1f0 fs/super.c:828 1 lock held by syz.2.827/7164: #0: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8d3305b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 38 Comm: kworker/u4:2 Not tainted 6.1.106-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_acquire+0x1230/0x1f80 kernel/locking/lockdep.c:5046 Code: 00 fc ff df 0f b6 04 10 84 c0 0f 85 53 0b 00 00 83 3d 23 a6 88 10 00 0f 84 b1 00 00 00 31 db 48 83 c3 40 48 89 d8 48 c1 e8 03 <80> 3c 10 00 74 08 48 89 df e8 72 93 77 00 48 83 3b 00 0f 84 9a 03 RSP: 0018:ffffc90000af79a0 EFLAGS: 00000802 RAX: 1ffffffff208664c RBX: ffffffff90433260 RCX: ffffffff816a8af0 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff9073b220 RBP: a05ca088a8fc9a52 R08: dffffc0000000000 R09: fffffbfff20e7645 R10: 0000000000000000 R11: dffffc0000000001 R12: ffff88801868c658 R13: ffff88801868bb80 R14: 0000000000000000 R15: 1ffff110030d18da FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555555b5c5c8 CR3: 0000000023dc0000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 rcu_lock_acquire include/linux/rcupdate.h:350 [inline] rcu_read_lock include/linux/rcupdate.h:791 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xe8/0x610 net/batman-adv/network-coding.c:719 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:295 vkms_vblank_simulate: vblank timer overrun