INFO: task kcompactd0:31 blocked for more than 143 seconds. Not tainted 6.2.0-rc5-next-20230127-syzkaller-08766-ge2f86c02fdc9 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kcompactd0 state:D stack:27376 pid:31 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5301 [inline] __schedule+0x245a/0x5a60 kernel/sched/core.c:6619 schedule+0xde/0x1a0 kernel/sched/core.c:6695 io_schedule+0xbe/0x130 kernel/sched/core.c:8881 folio_wait_bit_common+0x394/0x9b0 mm/filemap.c:1299 folio_lock include/linux/pagemap.h:950 [inline] migrate_folio_unmap mm/migrate.c:1168 [inline] migrate_pages_batch+0x291a/0x3620 mm/migrate.c:1674 migrate_pages+0x1b73/0x2300 mm/migrate.c:1961 compact_zone+0x1d3c/0x3ea0 mm/compaction.c:2420 proactive_compact_node+0x103/0x1b0 mm/compaction.c:2685 kcompactd+0x804/0xe30 mm/compaction.c:2993 kthread+0x2e8/0x3a0 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/13: #0: ffffffff8c794970 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:516 1 lock held by rcu_tasks_trace/14: #0: ffffffff8c794670 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x31/0xd80 kernel/rcu/tasks.h:516 1 lock held by khungtaskd/28: #0: ffffffff8c795540 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x390 kernel/locking/lockdep.c:6544 2 locks held by getty/4755: #0: ffff88802c015098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc900015802f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177 2 locks held by kworker/u4:11/6706: 1 lock held by syz-executor.1/23189: 1 lock held by syz-executor.1/23271: 1 lock held by syz-executor.1/23327: 1 lock held by syz-executor.1/23378: 1 lock held by syz-executor.1/23444: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.2.0-rc5-next-20230127-syzkaller-08766-ge2f86c02fdc9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 nmi_cpu_backtrace+0x316/0x3e0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x38f/0x440 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+0xe53/0x11b0 kernel/hung_task.c:377 kthread+0x2e8/0x3a0 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: 5165 Comm: kworker/u4:5 Not tainted 6.2.0-rc5-next-20230127-syzkaller-08766-ge2f86c02fdc9 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:__lock_is_held kernel/locking/lockdep.c:5428 [inline] RIP: 0010:lock_is_held_type+0x87/0x140 kernel/locking/lockdep.c:5761 Code: 62 4c 8a 31 db e8 a9 15 00 00 41 8b 84 24 30 0a 00 00 4d 8d ac 24 38 0a 00 00 65 ff 05 b2 c2 f2 75 85 c0 7f 12 e9 8a 00 00 00 <83> c3 01 41 3b 9c 24 30 0a 00 00 7d 7d 48 63 c3 48 89 ee 48 8d 04 RSP: 0018:ffffc9000457fb70 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8c795480 RDI: ffff888022e7e220 RBP: ffffffff8c795480 R08: 0000000000000000 R09: ffffffff8e74ac97 R10: fffffbfff1ce9592 R11: 0000000000000000 R12: ffff888022e7d7c0 R13: ffff888022e7e1f8 R14: 00000000ffffffff R15: ffff888022e7e220 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555556fe1848 CR3: 000000000c571000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:288 [inline] rcu_read_lock_sched_held+0x3e/0x70 kernel/rcu/update.c:125 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x5b3/0x780 kernel/locking/lockdep.c:5701 rcu_lock_release include/linux/rcupdate.h:332 [inline] rcu_read_unlock include/linux/rcupdate.h:806 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x86c/0xfe0 net/batman-adv/network-coding.c:719 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308