INFO: task udevd:4245 blocked for more than 145 seconds. Not tainted 5.15.180-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24672 pid: 4245 ppid: 3546 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 schedule+0x11b/0x1f0 kernel/sched/core.c:6459 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518 __mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743 device_lock include/linux/device.h:760 [inline] uevent_show+0x17e/0x340 drivers/base/core.c:2408 dev_attr_show+0x50/0xb0 drivers/base/core.c:2110 sysfs_kf_seq_show+0x313/0x4e0 fs/sysfs/file.c:61 seq_read_iter+0x43a/0xd10 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2166 [inline] new_sync_read fs/read_write.c:404 [inline] vfs_read+0xa93/0xe10 fs/read_write.c:485 ksys_read+0x1a2/0x2c0 fs/read_write.c:623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f0275869b6a RSP: 002b:00007ffeee5c0a18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00005617cb7aec50 RCX: 00007f0275869b6a RDX: 0000000000001000 RSI: 00005617cb7aee30 RDI: 0000000000000008 RBP: 00005617cb7aec50 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007ffeee5c0ef8 R15: 000000000000000a Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1f560 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 6 locks held by kworker/0:2/1111: #0: ffff88801c86b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90004557d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff88814750c220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff88814750c220 (&dev->mutex){....}-{3:3}, at: hub_event+0x208/0x54c0 drivers/usb/core/hub.c:5781 #3: ffff88807cd9e220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff88807cd9e220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:954 #4: ffff88807ccc21a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #4: ffff88807ccc21a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:954 #5: ffffffff8c9cf9d0 (umhelper_sem){++++}-{3:3}, at: usermodehelper_read_trylock+0x138/0x360 kernel/umh.c:217 1 lock held by udevd/3546: #0: ffff888021417d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x14d/0xa50 block/bdev.c:820 2 locks held by getty/3927: #0: ffff88814bfb7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900025ae2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158 4 locks held by udevd/4245: #0: ffff888060014790 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182 #1: ffff8880631b6088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112 #2: ffff888062a28a00 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113 #3: ffff88807cd9e220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #3: ffff88807cd9e220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17e/0x340 drivers/base/core.c:2408 2 locks held by kworker/0:6/4247: #0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003a7fd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 3 locks held by kworker/u4:7/4396: #0: ffff8880175cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900030ffd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8cb23a30 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x9c/0x4e0 kernel/rcu/tree.c:4039 2 locks held by kworker/u4:14/4417: #0: ffff8880b8f3a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 #1: ffff8880b8f27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4e1/0x810 kernel/sched/psi.c:882 3 locks held by kworker/1:16/4870: #0: ffff88801c86b538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003a3fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff888147774220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline] #2: ffff888147774220 (&dev->mutex){....}-{3:3}, at: hub_event+0x208/0x54c0 drivers/usb/core/hub.c:5781 3 locks held by kworker/0:15/4947: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc90003917d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #2: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845 3 locks held by kworker/0:19/6677: #0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc900037cfd20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffff88801ff13240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2cd/0x4120 drivers/net/netdevsim/fib.c:1480 1 lock held by syz-executor/7655: #0: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #0: ffffffff8cb23b28 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845 2 locks held by syz.8.673/7861: #0: ffff888021419918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:915 #1: ffff888146dc1468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070 2 locks held by syz.7.675/7867: #0: ffff888021417d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:915 #1: ffff888146dae468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x181/0x2a0 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+0xe72/0xeb0 kernel/hung_task.c:369 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4415 Comm: kworker/u4:13 Not tainted 5.15.180-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: phy14 ieee80211_iface_work RIP: 0010:lookup_chain_cache kernel/locking/lockdep.c:3681 [inline] RIP: 0010:lookup_chain_cache_add kernel/locking/lockdep.c:3701 [inline] RIP: 0010:validate_chain+0x16c/0x5930 kernel/locking/lockdep.c:3756 Code: b8 eb 83 b5 80 46 86 c8 61 49 0f af c6 48 c1 e8 2d 48 8d 1c c5 00 10 50 90 48 89 d8 48 c1 e8 03 48 89 44 24 50 42 80 3c 20 00 <74> 08 48 89 df e8 9a f2 66 00 48 89 5c 24 20 48 8b 1b 48 85 db 74 RSP: 0018:ffffc9000370f5a0 EFLAGS: 00000046 RAX: 1ffffffff20bbe8a RBX: ffffffff905df450 RCX: ffffffff81639e72 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff909911c0 RBP: ffffc9000370f850 R08: dffffc0000000000 R09: fffffbfff2132239 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: ffff88802c422948 R14: 5ee5968d454f87fa R15: ffff88802c422948 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2d4f4ff8 CR3: 000000007e29e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline] _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:368 [inline] ieee80211_ibss_work+0xe9/0x1480 net/mac80211/ibss.c:1695 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287