INFO: task udevd:4201 blocked for more than 144 seconds. Not tainted 5.15.189-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:23840 pid: 4201 ppid: 3563 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 io_schedule+0x7c/0xd0 kernel/sched/core.c:8484 wait_on_page_bit_common+0x815/0xe00 mm/filemap.c:1356 wait_on_page_bit mm/filemap.c:1417 [inline] wait_on_page_locked include/linux/pagemap.h:688 [inline] wait_on_page_read mm/filemap.c:3437 [inline] do_read_cache_page+0xb05/0x1030 mm/filemap.c:3480 read_mapping_page include/linux/pagemap.h:515 [inline] read_part_sector+0xd4/0x4f0 block/partitions/core.c:731 adfspart_check_ICS+0xbf/0xe00 block/partitions/acorn.c:360 check_partition block/partitions/core.c:148 [inline] blk_add_partitions block/partitions/core.c:616 [inline] bdev_disk_changed+0x917/0x16b0 block/partitions/core.c:702 blkdev_get_whole+0x2f9/0x390 block/bdev.c:682 blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827 blkdev_open+0x12d/0x2c0 block/fops.c:466 do_dentry_open+0x7ff/0xf80 fs/open.c:826 do_open fs/namei.c:3608 [inline] path_openat+0x2682/0x2f30 fs/namei.c:3742 do_filp_open+0x1b3/0x3e0 fs/namei.c:3769 do_sys_openat2+0x142/0x4a0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f0325d06407 RSP: 002b:00007ffc87ea9bd0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f0325c18880 RCX: 00007f0325d06407 RDX: 00000000000a0800 RSI: 000055a1051c2870 RDI: ffffffffffffff9c RBP: 000055a1051b6910 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000055a1051cb840 R13: 000055a1051ce420 R14: 0000000000000000 R15: 000055a1051cb840 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffff8880b9127848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4d6/0x810 kernel/sched/psi.c:891 1 lock held by khungtaskd/27: #0: ffffffff8c11c360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by getty/3947: #0: ffff88802bb02098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900021ce2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 1 lock held by udevd/4201: #0: ffff888020436918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by kworker/0:6/4302: #0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc900011efd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 3 locks held by kworker/u4:12/4346: 1 lock held by syz-executor/5369: #0: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x320/0x6b0 kernel/rcu/tree_exp.h:845 1 lock held by syz.0.1351/9341: #0: ffff888020436918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820 2 locks held by dhcpcd/10632: #0: ffff888074b10810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:787 [inline] #0: ffff888074b10810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:648 [inline] #0: ffff888074b10810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1336 #1: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8c120de8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x347/0x6b0 kernel/rcu/tree_exp.h:845 1 lock held by dhcpcd/10633: #0: ffff88801ba98120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1694 [inline] #0: ffff88801ba98120 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x35/0xce0 net/packet/af_packet.c:3213 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 6945 Comm: kworker/u4:14 Not tainted 5.15.189-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:debug_smp_processor_id+0x0/0x10 lib/smp_processor_id.c:60 Code: 12 8a e8 43 01 00 00 65 c7 05 b8 16 5b 76 00 00 00 00 48 c7 c7 00 cd 12 8a e8 2c 01 00 00 65 ff 0d a1 16 5b 76 5b c3 00 00 cc <48> c7 c7 e0 92 59 8a 48 c7 c6 20 93 59 8a eb 00 55 41 57 41 56 53 RSP: 0018:ffffc90004defbb8 EFLAGS: 00000282 RAX: ffffffff897d81e9 RBX: dffffc0000000000 RCX: ffff88802a1fbb80 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: dffffc0000000000 R09: fffffbfff1ff6e19 R10: fffffbfff1ff6e19 R11: 1ffffffff1ff6e18 R12: 00000000000000db R13: ffff88807b5306d8 R14: ffff888023230c80 R15: ffff88801799a4d0 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f732b84f198 CR3: 00000000179cf000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:331 [inline] rcu_is_watching+0x11/0xa0 kernel/rcu/tree.c:1123 rcu_read_lock include/linux/rcupdate.h:740 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0xe2/0x5c0 net/batman-adv/network-coding.c:723 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287