INFO: task udevd:5846 blocked for more than 143 seconds. Not tainted 6.13.0-rc1-syzkaller-00263-g3ca459eaba1b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:21392 pid:5846 tgid:5846 ppid:5202 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x1850/0x4c30 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 wait_for_reconnect drivers/block/nbd.c:1043 [inline] nbd_handle_cmd drivers/block/nbd.c:1085 [inline] nbd_queue_rq+0x7d9/0x2ef0 drivers/block/nbd.c:1143 blk_mq_dispatch_rq_list+0xad3/0x19d0 block/blk-mq.c:2119 __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:2353 blk_mq_flush_plug_list+0x118e/0x1870 block/blk-mq.c:2914 __blk_flush_plug+0x420/0x500 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] __submit_bio+0x46a/0x560 block/blk-core.c:637 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 submit_bh fs/buffer.c:2819 [inline] block_read_full_folio+0x93b/0xcd0 fs/buffer.c:2446 filemap_read_folio+0x14b/0x630 mm/filemap.c:2366 do_read_cache_folio+0x3f5/0x850 mm/filemap.c:3826 read_mapping_folio include/linux/pagemap.h:1011 [inline] read_part_sector+0xb3/0x330 block/partitions/core.c:722 adfspart_check_ICS+0xd9/0x9a0 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+0x72c/0x13f0 block/partitions/core.c:693 blkdev_get_whole+0x2d2/0x450 block/bdev.c:707 bdev_open+0x2d4/0xc50 block/bdev.c:916 blkdev_open+0x389/0x4f0 block/fops.c:627 do_dentry_open+0xbe1/0x1b70 fs/open.c:945 vfs_open+0x3e/0x330 fs/open.c:1075 do_open fs/namei.c:3828 [inline] path_openat+0x2c84/0x3590 fs/namei.c:3987 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1402 do_sys_open fs/open.c:1417 [inline] __do_sys_openat fs/open.c:1433 [inline] __se_sys_openat fs/open.c:1428 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1428 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: 0033:0x7f14747169a4 RSP: 002b:00007ffe82240980 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055cced1dfd30 RCX: 00007f14747169a4 RDX: 00000000000a0800 RSI: 000055cced1dda40 RDI: 00000000ffffff9c RBP: 000055cced1dda40 R08: 0000000000000001 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00000000000a0800 R13: 000055cced1d0890 R14: 0000000000000001 R15: 000055cced1b9910 Showing all locks held in the system: 3 locks held by kworker/u8:1/12: 1 lock held by rcu_exp_gp_kthr/19: 1 lock held by khungtaskd/30: #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937aa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 4 locks held by kworker/u8:3/52: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90000bc7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90000bc7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fca3910 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xcc0 net/core/net_namespace.c:586 #3: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: ppp_exit_net+0xe3/0x3d0 drivers/net/ppp/ppp_generic.c:1146 3 locks held by kworker/u8:5/796: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc900032c7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc900032c7d00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 2 locks held by getty/5583: #0: ffff88814d9820a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000331b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by udevd/5830: #0: ffff8880261eb4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff8881423e1110 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff8881423e1110 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff8881423e1110 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2353 #2: ffff88802632e178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2ef0 drivers/block/nbd.c:1135 1 lock held by syz-executor/5831: 2 locks held by syz-executor/5842: 3 locks held by udevd/5845: #0: ffff8880262274c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888026112b10 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888026112b10 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888026112b10 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2353 #2: ffff8880262f7178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2ef0 drivers/block/nbd.c:1135 3 locks held by udevd/5846: #0: ffff888143b194c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888025f35a90 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888025f35a90 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888025f35a90 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2353 #2: ffff8880262c7178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2ef0 drivers/block/nbd.c:1135 3 locks held by udevd/5847: #0: ffff8880262474c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf0/0xc50 block/bdev.c:904 #1: ffff888026138910 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:158 [inline] #1: ffff888026138910 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:249 [inline] #1: ffff888026138910 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x32b/0x500 block/blk-mq.c:2353 #2: ffff888026467178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xfe/0x2ef0 drivers/block/nbd.c:1135 3 locks held by kworker/1:7/9887: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9001b15fd00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9001b15fd00 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8e93cfb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:329 [inline] #2: ffffffff8e93cfb8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:976 5 locks held by kworker/u8:18/12540: 7 locks held by syz-executor/13870: #0: ffff888035fbc420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2964 [inline] #0: ffff888035fbc420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x225/0xd30 fs/read_write.c:675 #1: ffff888028717888 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1ea/0x500 fs/kernfs/file.c:325 #2: ffff8881447bcc38 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f55c368 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216 #4: ffff8880558200e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8880558200e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff8880558200e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1293 #5: ffff88805c487250 (&devlink->lock_key#8){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1675 #6: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x71/0x5c0 drivers/net/netdevsim/netdev.c:816 2 locks held by syz-executor/13895: #0: ffffffff8f526ba0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8f526ba0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8f526ba0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xbb0/0x20e0 net/core/rtnetlink.c:4008 1 lock held by syz.3.2756/14092: #0: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:702 [inline] #0: ffffffff8fcafd88 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3521 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc1-syzkaller-00263-g3ca459eaba1b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 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:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 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 UID: 0 PID: 63 Comm: kworker/u8:4 Not tainted 6.13.0-rc1-syzkaller-00263-g3ca459eaba1b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3797 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3817 [inline] RIP: 0010:validate_chain+0x1b9/0x5920 kernel/locking/lockdep.c:3872 Code: b8 eb 83 b5 80 46 86 c8 61 49 0f af c6 48 c1 e8 2d 48 8d 1c c5 c0 a7 e2 93 48 89 d8 48 c1 e8 03 48 89 44 24 68 42 80 3c 20 00 <74> 08 48 89 df e8 2d f4 8e 00 48 89 5c 24 48 48 8b 1b 48 85 db 74 RSP: 0018:ffffc90001547320 EFLAGS: 00000046 RAX: 1ffffffff281d10a RBX: ffffffff940e8850 RCX: ffffffff817b651e RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff942ba888 RBP: ffffc90001547620 R08: ffffffff942ba88f R09: 1ffffffff2857511 R10: dffffc0000000000 R11: fffffbfff2857512 R12: dffffc0000000000 R13: ffff88801c7c0b50 R14: d5b524e6a07d6eaa R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b3020cff8 CR3: 00000000337c4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 lock_timer_base+0x112/0x240 kernel/time/timer.c:1050 __mod_timer+0x1ca/0xeb0 kernel/time/timer.c:1131 queue_delayed_work_on+0x1ca/0x390 kernel/workqueue.c:2552 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 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