INFO: task udevd:5526 blocked for more than 143 seconds. Not tainted 6.10.0-syzkaller-09703-gd7e78951a8b8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:21400 pid:5526 tgid:5526 ppid:4556 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 wait_for_reconnect drivers/block/nbd.c:1023 [inline] nbd_handle_cmd drivers/block/nbd.c:1065 [inline] nbd_queue_rq+0x7cd/0x2f70 drivers/block/nbd.c:1123 blk_mq_dispatch_rq_list+0xb89/0x1b30 block/blk-mq.c:2032 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xb8a/0x1840 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xcb/0x140 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x576/0xae0 block/blk-mq.c:2245 blk_mq_flush_plug_list+0x1115/0x1880 block/blk-mq.c:2794 __blk_flush_plug+0x420/0x500 block/blk-core.c:1195 blk_finish_plug block/blk-core.c:1222 [inline] __submit_bio+0x422/0x560 block/blk-core.c:623 __submit_bio_noacct_mq block/blk-core.c:696 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:725 submit_bh fs/buffer.c:2829 [inline] block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2456 filemap_read_folio+0x1a0/0x790 mm/filemap.c:2355 do_read_cache_folio+0x134/0x820 mm/filemap.c:3789 read_mapping_folio include/linux/pagemap.h:913 [inline] read_part_sector+0xb3/0x330 block/partitions/core.c:712 adfspart_check_ICS+0xd9/0x9a0 block/partitions/acorn.c:360 check_partition block/partitions/core.c:138 [inline] blk_add_partitions block/partitions/core.c:579 [inline] bdev_disk_changed+0x72c/0x13d0 block/partitions/core.c:683 blkdev_get_whole+0x2d2/0x450 block/bdev.c:700 bdev_open+0x2d4/0xc60 block/bdev.c:909 blkdev_open+0x3e8/0x570 block/fops.c:630 do_dentry_open+0x970/0x1440 fs/open.c:959 vfs_open+0x3e/0x330 fs/open.c:1089 do_open fs/namei.c:3727 [inline] path_openat+0x2b3e/0x3470 fs/namei.c:3886 do_filp_open+0x235/0x490 fs/namei.c:3913 do_sys_openat2+0x13e/0x1d0 fs/open.c:1416 do_sys_open fs/open.c:1431 [inline] __do_sys_openat fs/open.c:1447 [inline] __se_sys_openat fs/open.c:1442 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1442 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbaf65169a4 RSP: 002b:00007fffc03c2620 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00005599af746b70 RCX: 00007fbaf65169a4 RDX: 00000000000a0800 RSI: 00005599af7384a0 RDI: 00000000ffffff9c RBP: 00005599af7384a0 R08: 0000000000000001 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 00005599af7306f0 R14: 0000000000000001 R15: 00005599af71e910 Showing all locks held in the system: 3 locks held by kworker/0:1/9: #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015080948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc900000e7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc900000e7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 1 lock held by khungtaskd/30: #0: ffffffff8e336e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:327 [inline] #0: ffffffff8e336e20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:839 [inline] #0: ffffffff8e336e20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6620 4 locks held by kworker/u8:6/1039: #0: ffff888015edd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888015edd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90003977d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90003977d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8f5f1b90 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:594 #3: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe9/0xa90 net/core/dev.c:11874 2 locks held by kworker/u8:8/1110: 1 lock held by dhcpcd/4770: #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101 2 locks held by getty/4861: #0: ffff88801dcd00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2211 3 locks held by udevd/5121: #0: ffff8880204384c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_open+0xf0/0xc60 block/bdev.c:897 #1: ffff88801fd9de90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline] #1: ffff88801fd9de90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline] #1: ffff88801fd9de90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x54d/0xae0 block/blk-mq.c:2245 #2: ffff888020510180 (&cmd->lock){+.+.}-{3:3}, at: nbd_queue_rq+0xfc/0x2f70 drivers/block/nbd.c:1115 3 locks held by udevd/5526: #0: ffff88801fef74c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_open+0xf0/0xc60 block/bdev.c:897 #1: ffff88801fa1ef90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:151 [inline] #1: ffff88801fa1ef90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:250 [inline] #1: ffff88801fa1ef90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x54d/0xae0 block/blk-mq.c:2245 #2: ffff8880204d0180 (&cmd->lock){+.+.}-{3:3}, at: nbd_queue_rq+0xfc/0x2f70 drivers/block/nbd.c:1115 1 lock held by syz-executor/11808: #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/11909: #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz.1.1635/11957: 1 lock held by syz.4.1646/12018: #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz.4.1646/12022: #0: ffffffff8e33c1f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:328 [inline] #0: ffffffff8e33c1f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:958 2 locks held by syz.0.1647/12021: #0: ffffffff8f663e10 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8f5fe708 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5f/0x8b0 net/wireless/nl80211.c:16547 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.10.0-syzkaller-09703-gd7e78951a8b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xfde/0x1020 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2477 Comm: kworker/u8:9 Not tainted 6.10.0-syzkaller-09703-gd7e78951a8b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:mark_lock+0x14d/0x350 kernel/locking/lockdep.c:4696 Code: 48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 6a 96 89 00 41 bc 01 00 00 00 44 85 33 74 16 44 89 e0 48 83 c4 10 5b 41 5c 41 5d <41> 5e 41 5f 5d c3 cc cc cc cc e8 d4 3b ff ff 85 c0 0f 84 33 01 00 RSP: 0018:ffffc900088e78d0 EFLAGS: 00000086 RAX: 0000000000000001 RBX: ffffffff92d2bc30 RCX: ffffffff816fef2a RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff92ff0600 RBP: 0000000000000009 R08: ffffffff92ff0607 R09: 1ffffffff25fe0c0 R10: dffffc0000000000 R11: fffffbfff25fe0c1 R12: ffff888029e1bc00 R13: ffff888029e1c6d8 R14: 0000000000000200 R15: ffff888029e1c730 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020c42030 CR3: 000000000e134000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4598 [inline] __lock_acquire+0xc35/0x2040 kernel/locking/lockdep.c:5096 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 rcu_lock_acquire include/linux/rcupdate.h:327 [inline] rcu_read_lock include/linux/rcupdate.h:839 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd40 kernel/workqueue.c:3390 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244