INFO: task udevd:5830 blocked for more than 143 seconds. Not tainted 6.14.0-rc2-syzkaller-00159-g07b598c0e6f0 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:21856 pid:5830 tgid:5830 ppid:1 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6856 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 wait_for_reconnect drivers/block/nbd.c:1104 [inline] nbd_handle_cmd drivers/block/nbd.c:1146 [inline] nbd_queue_rq+0x6dd/0xef0 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0xad3/0x19d0 block/blk-mq.c:2120 __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+0xd6/0x190 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x354/0x500 block/blk-mq.c:2354 blk_mq_flush_plug_list+0x118e/0x1870 block/blk-mq.c:2917 __blk_flush_plug+0x420/0x500 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] __submit_bio+0x54a/0x6a0 block/blk-core.c:642 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:744 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x9b3/0xae0 fs/buffer.c:2446 filemap_read_folio+0x148/0x3b0 mm/filemap.c:2390 do_read_cache_folio+0x373/0x5b0 mm/filemap.c:3960 read_mapping_folio include/linux/pagemap.h:1023 [inline] read_part_sector+0xb3/0x260 block/partitions/core.c:722 adfspart_check_ICS+0xcb/0xa20 block/partitions/acorn.c:360 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x77f/0x14d0 block/partitions/core.c:693 blkdev_get_whole+0x2d2/0x450 block/bdev.c:706 bdev_open+0x2d4/0xc50 block/bdev.c:915 blkdev_open+0x38e/0x4e0 block/fops.c:652 do_dentry_open+0xdec/0x1960 fs/open.c:956 vfs_open+0x3b/0x370 fs/open.c:1086 do_open fs/namei.c:3830 [inline] path_openat+0x2c81/0x3590 fs/namei.c:3989 do_filp_open+0x27f/0x4e0 fs/namei.c:4016 do_sys_openat2+0x13e/0x1d0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1454 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: 0033:0x7f370b1169a4 RSP: 002b:00007ffd9a394990 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000561051086620 RCX: 00007f370b1169a4 RDX: 00000000000a0800 RSI: 00005610510a3a40 RDI: 00000000ffffff9c RBP: 00005610510a3a40 R08: 0000000000000001 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 00005610510a0320 R14: 0000000000000001 R15: 000056105107f910 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb38f60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 3 locks held by kworker/u8:3/52: #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc90000bd7c60 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc90000bd7c60 ((work_completion)(&map->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8eb3e300 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3741 4 locks held by kworker/1:1H/58: #0: ffff8881416f7d48 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff8881416f7d48 ((wq_completion)kblockd){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc9000133fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000133fc60 ((work_completion)(&(&q->requeue_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffff8880257a0c90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:164 [inline] #2: ffff8880257a0c90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:256 [inline] #2: ffff8880257a0c90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #3: ffff8880262f51f8 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xcf/0xef0 drivers/block/nbd.c:1196 2 locks held by getty/5596: #0: ffff88814db330a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 3 locks held by udevd/5830: #0: ffff888143f094c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 #1: ffff888141bf2210 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:164 [inline] #1: ffff888141bf2210 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:256 [inline] #1: ffff888141bf2210 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff888026070178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xcf/0xef0 drivers/block/nbd.c:1196 1 lock held by udevd/5835: #0: ffff8880260054c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 3 locks held by udevd/5849: #0: ffff88802605b4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 #1: ffff888141bf2f90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:164 [inline] #1: ffff888141bf2f90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:256 [inline] #1: ffff888141bf2f90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff8880261a7178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xcf/0xef0 drivers/block/nbd.c:1196 1 lock held by udevd/5851: #0: ffff8880261294c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 3 locks held by udevd/5852: #0: ffff8880261f14c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 #1: ffff88802626e190 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:164 [inline] #1: ffff88802626e190 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:256 [inline] #1: ffff88802626e190 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff88802631e178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xcf/0xef0 drivers/block/nbd.c:1196 1 lock held by udevd/5853: #0: ffff8880263514c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 3 locks held by kworker/u8:8/6177: #0: ffff888031450148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline] #0: ffff888031450148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3317 #1: ffffc9000b6afc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline] #1: ffffc9000b6afc60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3317 #2: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline] #2: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x10e/0x16a0 net/ipv6/addrconf.c:4190 2 locks held by kworker/u8:9/6178: #0: ffff8880b863e958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 #1: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987 3 locks held by udevd/6946: #0: ffff888025eae4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 #1: ffff8880253c8710 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:164 [inline] #1: ffff8880253c8710 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:256 [inline] #1: ffff8880253c8710 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff8880260e7178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xcf/0xef0 drivers/block/nbd.c:1196 1 lock held by udevd/8158: #0: ffff88802612d4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 1 lock held by udevd/8160: #0: ffff88802605f4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 1 lock held by udevd/8976: #0: ffff8880261f54c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 3 locks held by udevd/9248: #0: ffff88802683b4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 #1: ffff88801ffe2690 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:164 [inline] #1: ffff88801ffe2690 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:256 [inline] #1: ffff88801ffe2690 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2354 #2: ffff8880268ce178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xcf/0xef0 drivers/block/nbd.c:1196 1 lock held by udevd/9281: #0: ffff8880263554c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:903 1 lock held by syz-executor/12938: #0: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline] #0: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996 2 locks held by syz.4.2120/13197: #0: ffffffff8fec7ad0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x328/0x570 net/core/net_namespace.c:512 #1: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: cfg802154_pernet_exit+0x1b/0xe0 net/ieee802154/core.c:351 1 lock held by syz.1.2146/13276: #0: ffff88807873a608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline] #0: ffff88807873a608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88807873a608 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1398 2 locks held by syz.1.2146/13278: #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6918 #1: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline] #1: ffffffff8eb3e438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x820 kernel/rcu/tree_exp.h:996 1 lock held by syz.1.2146/13279: #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: packet_mc_drop+0x28/0x5e0 net/packet/af_packet.c:3790 1 lock held by syz.1.2146/13281: #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: packet_mc_add+0x28/0xb40 net/packet/af_packet.c:3738 1 lock held by syz.1.2146/13283: #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline] #0: ffffffff8fed4248 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc2-syzkaller-00159-g07b598c0e6f0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:1 Not tainted 6.14.0-rc2-syzkaller-00159-g07b598c0e6f0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:kasan_check_range+0xc/0x290 mm/kasan/generic.c:188 Code: 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 55 41 57 41 56 41 54 53 01 48 85 f6 0f 84 a0 01 00 00 4c 8d 04 37 49 39 f8 0f 82 56 02 RSP: 0018:ffffc90000117950 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff819cd540 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff903cdc70 RBP: ffffc90000117aa8 R08: ffffffff8bd3767e R09: 1ffffffff28a8908 R10: dffffc0000000000 R11: fffffbfff28a8909 R12: 1ffff92000022f3c R13: ffffffff8bd3754b R14: ffff8880349c5800 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f267a863f50 CR3: 00000000347f6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 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:570 [inline] cpu_online include/linux/cpumask.h:1116 [inline] trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0xb0/0xa30 kernel/locking/lockdep.c:5862 rcu_lock_release include/linux/rcupdate.h:347 [inline] rcu_read_unlock include/linux/rcupdate.h:880 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline] batadv_nc_worker+0x28b/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3236 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3317 worker_thread+0x870/0xd30 kernel/workqueue.c:3398 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244