INFO: task syz.0.17:5945 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.17 state:D stack:25160 pid:5945 ppid:5896 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5380 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699 schedule+0xbd/0x170 kernel/sched/core.c:6773 io_schedule+0x80/0xd0 kernel/sched/core.c:9022 folio_wait_bit_common+0x6eb/0xf70 mm/filemap.c:1329 release_metapage+0x97/0x870 fs/jfs/jfs_metapage.c:764 discard_metapage fs/jfs/jfs_metapage.h:88 [inline] __get_metapage+0xa69/0xfa0 fs/jfs/jfs_metapage.c:644 dtSearch+0x591/0x21b0 fs/jfs/jfs_dtree.c:624 jfs_lookup+0x156/0x380 fs/jfs/namei.c:1459 lookup_open fs/namei.c:3474 [inline] open_last_lookups fs/namei.c:3564 [inline] path_openat+0x10b8/0x3190 fs/namei.c:3794 do_filp_open+0x1c5/0x3d0 fs/namei.c:3824 do_sys_openat2+0x12c/0x1c0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f29b278f749 RSP: 002b:00007ffc97a3b978 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f29b29e5fa0 RCX: 00007f29b278f749 RDX: 0000000000040042 RSI: 0000200000000240 RDI: ffffffffffffff9c RBP: 00007f29b2813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f29b29e5fa0 R14: 00007f29b29e5fa0 R15: 0000000000000004 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 2 locks held by kworker/u4:2/42: 3 locks held by kworker/u4:3/49: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90000ba7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90000ba7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff88802c9ca0e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 3 locks held by kworker/u4:5/991: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000416fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000416fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff8880263b80e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 3 locks held by kworker/u4:6/1120: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000418fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000418fd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff88807bfcc0e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 3 locks held by kworker/u4:7/2903: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000bb27d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000bb27d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888024c960e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 3 locks held by kworker/u4:8/2948: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000bf47d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000bf47d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff88807c7a20e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 3 locks held by kworker/u4:9/3549: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000cc87d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000cc87d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888026ae80e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 2 locks held by getty/5528: #0: ffff88814cede0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000326e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 1 lock held by syz.0.17/5945: #0: ffff8880601533d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff8880601533d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff8880601533d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 1 lock held by syz.1.18/5968: #0: ffff888060238ed0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff888060238ed0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff888060238ed0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 1 lock held by syz.2.19/5991: #0: ffff88806017bd10 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff88806017bd10 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff88806017bd10 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 1 lock held by syz.3.20/6018: #0: ffff8880600b2150 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff8880600b2150 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff8880600b2150 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 1 lock held by syz.4.21/6046: #0: ffff88806023b3d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff88806023b3d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff88806023b3d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 3 locks held by kworker/u4:11/6073: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90003fe7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90003fe7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888058b6e0e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 1 lock held by syz.5.22/6074: #0: ffff8880600b58d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff8880600b58d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff8880600b58d0 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 3 locks held by kworker/u4:12/6075: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900038d7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900038d7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff8880551380e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 1 lock held by syz.6.23/6108: #0: ffff888073c63d10 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff888073c63d10 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff888073c63d10 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 3 locks held by kworker/u4:13/6109: #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888140069d38 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900041afd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900041afd00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888076c680e0 (&type->s_umount_key#56){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607 1 lock held by syz.7.24/6137: #0: ffff888073f92150 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff888073f92150 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff888073f92150 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 1 lock held by syz.8.25/6165: #0: ffff888073f97490 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff888073f97490 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: open_last_lookups fs/namei.c:3561 [inline] #0: ffff888073f97490 (&type->i_mutex_dir_key#9){+.+.}-{3:3}, at: path_openat+0x7c6/0x3190 fs/namei.c:3794 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 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+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 6019 Comm: kworker/u4:10 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:arch_irqs_disabled_flags arch/x86/include/asm/irqflags.h:126 [inline] RIP: 0010:lockdep_hardirqs_on_prepare+0xe8/0x760 kernel/locking/lockdep.c:4340 Code: b4 e9 96 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 0b 05 00 00 83 3d 08 f2 82 15 00 75 6c 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 44 24 41 02 0f 85 87 03 00 00 48 c7 c0 80 b4 e9 96 48 c1 e8 03 RSP: 0018:ffffc90003677960 EFLAGS: 00000046 RAX: 0000000000000004 RBX: 1ffff920006cef30 RCX: ffffffff96e9b403 RDX: dffffc0000000000 RSI: ffffffff8afc6f60 RDI: ffffffff8afc6f20 RBP: ffffc90003677a08 R08: ffffffff8e4a212f R09: 1ffffffff1c94425 R10: dffffc0000000000 R11: fffffbfff1c94426 R12: ffffffff8a302e61 R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff920006cef44 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055f0ca399a38 CR3: 000000000cb30000 CR4: 00000000003506f0 Call Trace: trace_hardirqs_on+0x28/0x40 kernel/trace/trace_preemptirq.c:61 __local_bh_enable_ip+0x12e/0x1c0 kernel/softirq.c:411 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x311/0x3a0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x328/0x610 net/batman-adv/network-coding.c:720 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293