INFO: task kworker/u4:8:6066 blocked for more than 143 seconds. Not tainted 5.19.0-rc4-next-20220628-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:8 state:D stack:26528 pid: 6066 ppid: 2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:1) Call Trace: context_switch kernel/sched/core.c:5184 [inline] __schedule+0xa09/0x4f10 kernel/sched/core.c:6496 schedule+0xd2/0x1f0 kernel/sched/core.c:6568 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1911 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common+0x378/0x530 kernel/sched/completion.c:106 f2fs_issue_checkpoint+0x363/0x460 fs/f2fs/checkpoint.c:1865 f2fs_sync_fs+0x2f9/0x420 fs/f2fs/super.c:1653 f2fs_balance_fs_bg+0xc6a/0xef0 fs/f2fs/segment.c:477 f2fs_write_node_pages+0x148/0xc40 fs/f2fs/node.c:2100 do_writepages+0x1ab/0x690 mm/page-writeback.c:2468 __writeback_single_inode+0x121/0x10b0 fs/fs-writeback.c:1588 writeback_sb_inodes+0x54d/0xf10 fs/fs-writeback.c:1866 __writeback_inodes_wb+0xc6/0x280 fs/fs-writeback.c:1937 wb_writeback+0x7e9/0xc20 fs/fs-writeback.c:2042 wb_check_old_data_flush fs/fs-writeback.c:2142 [inline] wb_do_writeback fs/fs-writeback.c:2195 [inline] wb_workfn+0x845/0x1230 fs/fs-writeback.c:2223 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8bd864f0 ( rcu_tasks.tasks_gp_mutex ){+.+.}-{3:3} , at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8bd861f0 ( rcu_tasks_trace.tasks_gp_mutex ){+.+.}-{3:3} , at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507 1 lock held by khungtaskd/28: #0: ffffffff8bd87040 ( rcu_read_lock ){....}-{1:2} , at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6491 2 locks held by getty/3280: #0: ffff8880260d5098 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002d162f0 ( &ldata->atomic_read_lock ){+.+.}-{3:3} , at: n_tty_read+0xe50/0x13c0 drivers/tty/n_tty.c:2177 2 locks held by kworker/0:5/3682: #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888011866538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc90003cafda8 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 5 locks held by kworker/u4:7/3719: 3 locks held by kworker/u4:8/6066: #0: ffff888016eac938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888016eac938 ((wq_completion)writeback){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888016eac938 ((wq_completion)writeback){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888016eac938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline] #0: ffff888016eac938 ((wq_completion)writeback){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] #0: ffff888016eac938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc9000478fda8 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffff88803ab620e0 ( &type->s_umount_key #67 ){++++}-{3:3} , at: trylock_super+0x1d/0x100 fs/super.c:415 4 locks held by kworker/u4:13/8865: #0: ffff8880119bd938 ( (wq_completion)netns ){+.+.}-{0:0} , at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] , at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] , at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] , at: set_work_data kernel/workqueue.c:636 [inline] , at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline] , at: process_one_work+0x87a/0x1610 kernel/workqueue.c:2260 #1: ffffc9000a887da8 ( net_cleanup_work ){+.+.}-{0:0} , at: process_one_work+0x8ae/0x1610 kernel/workqueue.c:2264 #2: ffffffff8d58ea10 ( pernet_ops_rwsem ){++++}-{3:3} , at: cleanup_net+0x9b/0xb00 net/core/net_namespace.c:557 #3: ffffffff8bd91800 ( rcu_state.barrier_mutex ){+.+.}-{3:3} , at: rcu_barrier+0x44/0x630 kernel/rcu/tree.c:3783 5 locks held by f2fs_ckpt-7:1/8882: 3 locks held by syz-executor.3/11963: #0: ffffffff8d58ea10 ( pernet_ops_rwsem ){++++}-{3:3} , at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:468 #1: ffffffff8d5a31a8 ( rtnl_mutex ){+.+.}-{3:3} , at: ip_tunnel_delete_nets+0x8e/0x5b0 net/ipv4/ip_tunnel.c:1119 #2: ffffffff8bd91938 ( rcu_state.exp_mutex ){+.+.}-{3:3} , at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] , at: synchronize_rcu_expedited+0x562/0x670 kernel/rcu/tree_exp.h:940 2 locks held by syz-executor.5/11966: #0: ffffffff8d58ea10 ( pernet_ops_rwsem ){++++}-{3:3} , at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:468 #1: ffffffff8d5a31a8 ( rtnl_mutex ){+.+.}-{3:3} , at: ip_tunnel_delete_nets+0x8e/0x5b0 net/ipv4/ip_tunnel.c:1119 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 5.19.0-rc4-next-20220628-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xc18/0xf50 kernel/hung_task.c:369 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 1085 Comm: kworker/u4:5 Not tainted 5.19.0-rc4-next-20220628-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 Workqueue: bat_events batadv_nc_worker RIP: 0010:__sanitizer_cov_trace_pc+0x5c/0x60 kernel/kcov.c:218 Code: 82 70 15 00 00 83 f8 02 75 20 48 8b 8a 78 15 00 00 8b 92 74 15 00 00 48 8b 01 48 83 c0 01 48 39 c2 76 07 48 89 01 48 89 34 c1 0f 1f 00 41 55 41 54 49 89 fc 55 48 bd eb 83 b5 80 46 86 c8 61 RSP: 0018:ffffc900047efc80 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff888037a000f8 RCX: 0000000000000000 RDX: ffff88801f0f57c0 RSI: ffffffff8913017d RDI: ffff88801f0f5bfc RBP: 0000000000000001 R08: 0000000000000004 R09: 000000000000001f R10: 0000000000000400 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: 000000000000001f FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555557361848 CR3: 000000000ba8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:280 [inline] rcu_read_lock include/linux/rcupdate.h:706 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x10d/0xfa0 net/batman-adv/network-coding.c:719 process_one_work+0x991/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302