INFO: task kworker/u4:8:2852 blocked for more than 143 seconds. Not tainted 6.7.0-rc3-syzkaller-00284-g815fb87b7530 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:8 state:D stack:24632 pid:2852 tgid:2852 ppid:2 flags:0x00004000 Workqueue: writeback wb_workfn (flush-7:0) Call Trace: context_switch kernel/sched/core.c:5376 [inline] __schedule+0xedb/0x5af0 kernel/sched/core.c:6688 __schedule_loop kernel/sched/core.c:6763 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6778 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6835 rwsem_down_write_slowpath kernel/locking/rwsem.c:1178 [inline] __down_write_common+0x948/0x1400 kernel/locking/rwsem.c:1306 f2fs_down_write fs/f2fs/f2fs.h:2133 [inline] f2fs_balance_fs+0x553/0x750 fs/f2fs/segment.c:437 f2fs_write_inode+0x4a7/0xd70 fs/f2fs/inode.c:823 write_inode fs/fs-writeback.c:1473 [inline] __writeback_single_inode+0xa91/0xe90 fs/fs-writeback.c:1690 writeback_sb_inodes+0x599/0x1080 fs/fs-writeback.c:1916 __writeback_inodes_wb+0xff/0x2d0 fs/fs-writeback.c:1987 wb_writeback+0x7f8/0xaa0 fs/fs-writeback.c:2094 wb_check_old_data_flush fs/fs-writeback.c:2198 [inline] wb_do_writeback fs/fs-writeback.c:2251 [inline] wb_workfn+0xa0c/0xfe0 fs/fs-writeback.c:2279 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cfabbe0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8cfabbe0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8cfabbe0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 3 locks held by kworker/u4:4/59: #0: ffff8880b993c718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558 #1: ffff8880b9928888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2d9/0x900 kernel/sched/psi.c:988 #2: ffff8880b99297d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5d/0x200 kernel/time/timer.c:999 4 locks held by kworker/u4:8/2852: #0: ffff888140054d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x789/0x15d0 kernel/workqueue.c:2605 #1: ffffc9000a647d80 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7eb/0x15d0 kernel/workqueue.c:2606 #2: ffff888065aa20e0 (&type->s_umount_key#53){++++}-{3:3}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:610 #3: ffff88807e42d2a8 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2133 [inline] #3: ffff88807e42d2a8 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x553/0x750 fs/f2fs/segment.c:437 2 locks held by getty/4815: #0: ffff88802a6da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc6/0x1490 drivers/tty/n_tty.c:2201 4 locks held by syz-executor.0/5580: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc3-syzkaller-00284-g815fb87b7530 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 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+0xf87/0x1210 kernel/hung_task.c:379 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1092 Comm: kworker/u4:7 Not tainted 6.7.0-rc3-syzkaller-00284-g815fb87b7530 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_region_inline mm/kasan/generic.c:172 [inline] RIP: 0010:kasan_check_range+0x1b/0x190 mm/kasan/generic.c:187 Code: 41 5c c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 66 0f 1f 00 48 85 f6 0f 84 48 01 00 00 48 89 f8 41 54 44 0f b6 c2 48 01 f0 55 53 <0f> 82 c6 00 00 00 48 b8 ff ff ff ff ff 7f ff ff 48 39 f8 0f 83 b3 RSP: 0018:ffffc900049f7aa8 EFLAGS: 00000282 RAX: ffffffff8f193b98 RBX: 1ffff9200093ef5b RCX: ffffffff81681bf7 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8f193b90 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000400 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8cfabbe0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f990bf0652e CR3: 000000000cd77000 CR4: 0000000000350ef0 Call Trace: instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:504 [inline] cpu_online include/linux/cpumask.h:1104 [inline] trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0xb7/0x520 kernel/locking/lockdep.c:5725 rcu_lock_acquire include/linux/rcupdate.h:301 [inline] rcu_read_lock include/linux/rcupdate.h:747 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x16e/0x10e0 net/batman-adv/network-coding.c:719 process_one_work+0x886/0x15d0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242