INFO: task segctord:17356 blocked for more than 143 seconds. Not tainted 6.3.0-rc7-syzkaller-00181-g8e41e0a57566 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:segctord state:D stack:28696 pid:17356 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5307 [inline] __schedule+0x173b/0x4630 kernel/sched/core.c:6625 schedule+0xc3/0x180 kernel/sched/core.c:6701 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6760 rwsem_down_write_slowpath+0xedd/0x13a0 kernel/locking/rwsem.c:1178 __down_write_common+0x1aa/0x200 kernel/locking/rwsem.c:1306 nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357 nilfs_segctor_thread_construct fs/nilfs2/segment.c:2508 [inline] nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2592 kthread+0x270/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cf25570 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cf25d70 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 1 lock held by khungtaskd/28: #0: ffffffff8cf253a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:4/56: #0: ffff888012479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363 #1: ffffc90001577d20 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365 2 locks held by getty/4746: #0: ffff888027b4a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900015a02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ab/0x1db0 drivers/tty/n_tty.c:2177 2 locks held by kworker/u4:7/5536: 5 locks held by kworker/u4:11/6170: 3 locks held by kworker/1:23/13464: #0: ffff888012470d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363 #1: ffffc90005997d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365 #2: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline] #2: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a3/0x890 kernel/rcu/tree_exp.h:989 2 locks held by kworker/1:28/13469: #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x77e/0x10e0 kernel/workqueue.c:2363 #1: ffffc90005c2fd20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7c8/0x10e0 kernel/workqueue.c:2365 5 locks held by syz-executor.0/17352: 1 lock held by segctord/17356: #0: ffff88807c71a2a0 (&nilfs->ns_segctor_sem){++++}-{3:3}, at: nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357 3 locks held by syz-executor.0/17419: 4 locks held by syz-executor.3/20263: #0: ffffffff8d6537c8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x380 drivers/char/misc.c:129 #1: ffffffff8cddbec8 (system_transition_mutex){+.+.}-{3:3}, at: lock_system_sleep+0x5f/0xa0 kernel/power/main.c:28 #2: ffffffff8cdf9b70 ((pm_chain_head).rwsem){++++}-{3:3}, at: blocking_notifier_call_chain_robust+0x57/0x90 kernel/notifier.c:346 #3: ffffffff8cf2a740 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x540 kernel/rcu/tree.c:3956 1 lock held by syz-executor.4/20262: #0: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #0: ffffffff8cf2a878 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x46c/0x890 kernel/rcu/tree_exp.h:989 1 lock held by syz-executor.5/20320: #0: ffffffff8d6537c8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x5c/0x380 drivers/char/misc.c:129 1 lock held by syz-executor.0/20333: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.3.0-rc7-syzkaller-00181-g8e41e0a57566 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 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:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xec2/0xf00 kernel/hung_task.c:379 kthread+0x270/0x300 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: 1200 Comm: kworker/u4:6 Not tainted 6.3.0-rc7-syzkaller-00181-g8e41e0a57566 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_acquire+0x5/0x520 kernel/locking/lockdep.c:5637 Code: a2 fd ff ff 90 f3 0f 1e fa 65 8b 05 0d a0 99 7e a9 00 ff ff 00 0f 95 c0 c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec 20 01 00 RSP: 0018:ffffc90005827bd8 EFLAGS: 00000246 RAX: ffffffff8a6ffe4e RBX: ffff888022488478 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8cf253a0 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: dffffc0000000001 R12: 000000000000008f R13: dffffc0000000000 R14: ffff888020f88c80 R15: ffff8880220a1400 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6904d0e805 CR3: 000000000cd30000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire+0x2e/0x40 include/linux/rcupdate.h:327 rcu_read_lock include/linux/rcupdate.h:773 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xc5/0x5c0 net/batman-adv/network-coding.c:719 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2390 worker_thread+0xa63/0x1210 kernel/workqueue.c:2537 kthread+0x270/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308