INFO: task kworker/u4:7:5571 blocked for more than 143 seconds. Not tainted 6.5.0-rc4-syzkaller-00251-gf0ab9f34e59e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:7 state:D stack:19832 pid:5571 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:2) Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x1873/0x48f0 kernel/sched/core.c:6710 schedule+0xc3/0x180 kernel/sched/core.c:6786 io_schedule+0x8c/0x100 kernel/sched/core.c:9028 bit_wait_io+0x12/0xc0 kernel/sched/wait_bit.c:209 __wait_on_bit_lock+0xbd/0x1a0 kernel/sched/wait_bit.c:90 out_of_line_wait_on_bit_lock+0x1d4/0x250 kernel/sched/wait_bit.c:117 __ext4_get_inode_loc+0x684/0xe50 fs/ext4/inode.c:4356 __ext4_get_inode_loc_noinmem fs/ext4/inode.c:4463 [inline] ext4_write_inode+0x3a3/0x740 fs/ext4/inode.c:5161 write_inode fs/fs-writeback.c:1456 [inline] __writeback_single_inode+0x69b/0xfa0 fs/fs-writeback.c:1668 writeback_sb_inodes+0x8e3/0x11d0 fs/fs-writeback.c:1894 __writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:1965 wb_writeback+0x461/0xc60 fs/fs-writeback.c:2072 wb_check_background_flush fs/fs-writeback.c:2142 [inline] wb_do_writeback fs/fs-writeback.c:2230 [inline] wb_workfn+0xc6f/0xff0 fs/fs-writeback.c:2257 process_one_work+0x92c/0x12c0 kernel/workqueue.c:2597 worker_thread+0xa63/0x1210 kernel/workqueue.c:2748 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/13: #0: ffffffff8d328db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:522 1 lock held by rcu_tasks_trace/14: #0: ffffffff8d329170 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:522 1 lock held by khungtaskd/28: #0: ffffffff8d328be0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/1:3/4486: #0: ffff888012870d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7e3/0x12c0 kernel/workqueue.c:2569 #1: ffffc900031dfd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x82b/0x12c0 kernel/workqueue.c:2571 2 locks held by getty/4769: #0: ffff88802947e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b1/0x1dc0 drivers/tty/n_tty.c:2187 2 locks held by kworker/1:5/5110: #0: ffff888012870d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7e3/0x12c0 kernel/workqueue.c:2569 #1: ffffc90005a8fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x82b/0x12c0 kernel/workqueue.c:2571 3 locks held by kworker/1:11/5436: #0: ffff888012870d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7e3/0x12c0 kernel/workqueue.c:2569 #1: ffffc90006c9fd00 (key_gc_work){+.+.}-{0:0}, at: process_one_work+0x82b/0x12c0 kernel/workqueue.c:2571 #2: ffffffff8d32e278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #2: ffffffff8d32e278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:992 3 locks held by kworker/u4:7/5571: #0: ffff888143673938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7e3/0x12c0 kernel/workqueue.c:2569 #1: ffffc900094efd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x82b/0x12c0 kernel/workqueue.c:2571 #2: ffff8880351f00e0 (&type->s_umount_key#30){++++}-{3:3}, at: trylock_super+0x1f/0xf0 fs/super.c:413 2 locks held by kworker/u4:8/5697: #0: ffff8880b993bf98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:558 #1: ffff8880b99287c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:999 2 locks held by kworker/1:16/7183: #0: ffff888012872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x7e3/0x12c0 kernel/workqueue.c:2569 #1: ffffc9000cdb7d00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x82b/0x12c0 kernel/workqueue.c:2571 2 locks held by syz-executor.2/18277: 2 locks held by syz-executor.3/20271: #0: ffff88803a51e0e0 (&type->s_umount_key#59/1){+.+.}-{3:3}, at: alloc_super+0x217/0x920 fs/super.c:228 #1: ffffffff8d32e278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #1: ffffffff8d32e278 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:992 1 lock held by syz-executor.0/20274: #0: ffff88802157e0e0 (&type->s_umount_key#59/1){+.+.}-{3:3}, at: alloc_super+0x217/0x920 fs/super.c:228 3 locks held by syz-executor.2/20314: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.5.0-rc4-syzkaller-00251-gf0ab9f34e59e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x498/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x187/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xec2/0xf00 kernel/hung_task.c:379 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3189 Comm: kworker/u4:6 Not tainted 6.5.0-rc4-syzkaller-00251-gf0ab9f34e59e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:444 [inline] RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] RIP: 0010:rcu_is_watching+0x55/0xb0 kernel/rcu/tree.c:695 Code: 78 c8 8c 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 9c 14 70 00 48 c7 c3 88 6a 03 00 49 03 1e 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 1e 8b 03 65 ff 0d f1 54 8f 7e 74 0c 83 e0 RSP: 0018:ffffc9000e5f7b98 EFLAGS: 00000a02 RAX: 1ffff11017306d51 RBX: ffff8880b9836a88 RCX: ffff88802af49dc0 RDX: ffff88802af49dc0 RSI: ffffffff8b58a3a0 RDI: ffffffff8b58a360 RBP: 0000000000000001 R08: ffffffff8a8c67a9 R09: 1ffffffff20f6260 R10: dffffc0000000000 R11: fffffbfff20f6261 R12: 000000000000025d R13: dffffc0000000000 R14: ffffffff8cc878e0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9dac4c66e4 CR3: 000000002e025000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_unlock include/linux/rcupdate.h:778 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x1d2/0x5c0 net/batman-adv/network-coding.c:719 process_one_work+0x92c/0x12c0 kernel/workqueue.c:2597 worker_thread+0xa63/0x1210 kernel/workqueue.c:2748 kthread+0x2b8/0x350 kernel/kthread.c:389 ret_from_fork+0x2e/0x60 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304