INFO: task syz-executor:7510 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22216 pid:7510 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5381 [inline] __schedule+0x14d2/0x44d0 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 io_schedule+0x80/0xd0 kernel/sched/core.c:9023 folio_wait_bit_common+0x6eb/0xf70 mm/filemap.c:1329 __filemap_get_folio+0xbc/0xbc0 mm/filemap.c:1910 truncate_inode_pages_range+0x40a/0xf00 mm/truncate.c:401 evict+0x499/0x870 fs/inode.c:707 dispose_list fs/inode.c:738 [inline] evict_inodes+0x5fe/0x690 fs/inode.c:792 generic_shutdown_super+0x97/0x2b0 fs/super.c:672 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1259 task_work_run+0x1ce/0x250 kernel/task_work.c:245 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f5dfc190a77 RSP: 002b:00007ffc4cd69cc8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f5dfc213d7d RCX: 00007f5dfc190a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc4cd69d80 RBP: 00007ffc4cd69d80 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc4cd6ae10 R13: 00007f5dfc213d7d R14: 000000000005ebad R15: 00007ffc4cd6ae50 Showing all locks held in the system: 5 locks held by kworker/0:0/8: #0: ffff888019ef9138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888019ef9138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900000d7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900000d7d00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffff888142f1a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline] #2: ffff888142f1a190 (&dev->mutex){....}-{3:3}, at: hub_event+0x185/0x49c0 drivers/usb/core/hub.c:5861 #3: ffff88805b114190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline] #3: ffff88805b114190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x89/0x400 drivers/base/dd.c:1005 #4: ffff88814765da78 (&(&priv->bus_notifier)->rwsem){++++}-{3:3}, at: blocking_notifier_call_chain+0x54/0x90 kernel/notifier.c:387 3 locks held by kworker/u4:0/11: #0: ffff88802c2c6138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff88802c2c6138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90000107d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffffffff8dfb6208 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x14e0 net/ipv6/addrconf.c:4176 1 lock held by khungtaskd/29: #0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline] #0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline] #0: ffffffff8cd2ffa0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633 3 locks held by kworker/u4:2/32: #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90000a8fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90000a8fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffffffff8dfb6208 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:286 3 locks held by kworker/u4:3/49: #0: ffff8880b8f3c018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:559 #1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline] #1: ffff8880b8f289c0 (psi_seq){-.-.}-{0:0}, at: __schedule+0x20ee/0x44d0 kernel/sched/core.c:6695 #2: ffff8880b8f29598 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999 2 locks held by kworker/u4:4/65: #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc900015c7d00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc900015c7d00 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 2 locks held by kworker/u4:8/2966: #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017871538 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc9000c0d7d00 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc9000c0d7d00 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 2 locks held by getty/5525: #0: ffff88814cced0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217 3 locks held by kworker/0:5/5839: #0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017870938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90004a8fd00 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90004a8fd00 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #2: ffffffff8dfb6208 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 2 locks held by kworker/0:6/5857: #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #0: ffff888017872538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 #1: ffffc90004aafd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline] #1: ffffc90004aafd00 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711 4 locks held by udevd/7361: #0: ffff888078c74d58 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xb1/0xd50 fs/seq_file.c:182 #1: ffff88805b47ac88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x5c/0x410 fs/kernfs/file.c:172 #2: ffff888062b85008 (kn->active#30){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888062b85008 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x410 fs/kernfs/file.c:173 #3: ffff88805b114190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:1000 [inline] #3: ffff88805b114190 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by syz-executor/7510: #0: ffff88807d0ca0e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock fs/super.c:56 [inline] #0: ffff88807d0ca0e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88807d0ca0e0 (&type->s_umount_key#102){++++}-{3:3}, at: deactivate_super+0xa4/0xe0 fs/super.c:513 1 lock held by syz.1.410/7862: #0: ffff88807d0ca0e0 (&type->s_umount_key#102){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] #0: ffff88807d0ca0e0 (&type->s_umount_key#102){++++}-{3:3}, at: super_lock+0x167/0x360 fs/super.c:117 3 locks held by syz.8.607/8753: #0: ffff88805314b820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline] #0: ffff88805314b820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline] #0: ffff88805314b820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x9b/0x230 net/socket.c:1420 #1: ffff888023ca0130 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline] #1: ffff888023ca0130 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x1cd/0x860 net/can/bcm.c:1562 #2: ffffffff8cd35978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline] #2: ffffffff8cd35978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x830 kernel/rcu/tree_exp.h:1004 2 locks held by syz.0.616/8783: #0: ffffffff8dfb6208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8dfb6208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x76f/0xf10 net/core/rtnetlink.c:6469 #1: ffffffff8cd35978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #1: ffffffff8cd35978 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf41/0xf80 kernel/hung_task.c:379 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 5757 Comm: kworker/1:2 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events free_obj_work RIP: 0010:unwind_get_return_address+0x3b/0xc0 arch/x86/kernel/unwind_orc.c:369 Code: 00 00 00 fc ff df e8 44 09 4b 00 48 89 d8 48 c1 e8 03 42 0f b6 04 30 84 c0 75 6e 8b 2b 31 ff 89 ee e8 d9 0c 4b 00 85 ed 74 4a <48> 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 RSP: 0018:ffffc900045cf620 EFLAGS: 00000202 RAX: ffffffff813aa1d7 RBX: ffffc900045cf648 RCX: 0000000000000000 RDX: ffff88805bf51e00 RSI: 0000000000000001 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffff88805bf51e00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000000 R12: ffff88805bf51e00 R13: ffffc900045cfa60 R14: dffffc0000000000 R15: ffffc900045cf648 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555562c095c8 CR3: 000000000cb30000 CR4: 00000000003506e0 Call Trace: arch_stack_walk+0x11d/0x190 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3852 free_obj_work+0x414/0x580 lib/debugobjects.c:332 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293