INFO: task syz-executor:6909 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22456 pid:6909 tgid:6909 ppid:1 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5387 [inline] __schedule+0x169e/0x54f0 kernel/sched/core.c:7188 __schedule_loop kernel/sched/core.c:7267 [inline] schedule+0x164/0x360 kernel/sched/core.c:7282 fuse_chan_wait_aborted+0x15b/0x250 fs/fuse/dev.c:2212 fuse_conn_destroy+0x1e7/0x3e0 fs/fuse/inode.c:1969 fuse_sb_destroy fs/fuse/inode.c:1988 [inline] fuse_kill_sb_anon+0x1ef/0x270 fs/fuse/inode.c:2001 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f324198da57 RSP: 002b:00007ffe29478c18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f3241a22048 RCX: 00007f324198da57 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe29478cd0 RBP: 00007ffe29478cd0 R08: 00007ffe29479cd0 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe29479d60 R13: 00007f3241a22048 R14: 0000000000032af5 R15: 00007ffe29479da0 Showing all locks held in the system: 1 lock held by khungtaskd/39: #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777 2 locks held by kworker/u8:3/56: #0: ffff88813fe1c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline] #0: ffff88813fe1c138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399 #1: ffffc9000122fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline] #1: ffffc9000122fc40 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399 3 locks held by kworker/0:2/820: #0: ffff88801d6f9938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline] #0: ffff88801d6f9938 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399 #1: ffffc90005487c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline] #1: ffffc90005487c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399 #2: ffff88802a936210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1039 [inline] #2: ffff88802a936210 (&dev->mutex){....}-{4:4}, at: hub_event+0x17c/0x4f60 drivers/usb/core/hub.c:5899 9 locks held by kworker/u8:13/1418: #0: ffff88801aea6138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3280 [inline] #0: ffff88801aea6138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0xa2e/0x1910 kernel/workqueue.c:3399 #1: ffffc90006a2fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3281 [inline] #1: ffffc90006a2fc40 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0xa69/0x1910 kernel/workqueue.c:3399 #2: ffffffff8f790ce0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x800 net/core/net_namespace.c:673 #3: ffff88802bcf0160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1039 [inline] #3: ffff88802bcf0160 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:124 [inline] #3: ffff88802bcf0160 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0x129/0x420 net/devlink/core.c:555 #4: ffff88803240e310 (&devlink->lock_key#11){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:292 [inline] #4: ffff88803240e310 (&devlink->lock_key#11){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:125 [inline] #4: ffff88803240e310 (&devlink->lock_key#11){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0x142/0x420 net/devlink/core.c:555 #5: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_init_netdevsim drivers/net/netdevsim/netdev.c:1055 [inline] #5: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_create+0x894/0x1170 drivers/net/netdevsim/netdev.c:1149 #6: ffff8880b863a288 ((lock)){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #6: ffff8880b863a288 ((lock)){+.+.}-{3:3}, at: __radix_tree_preload+0x141/0x870 lib/radix-tree.c:334 #7: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #7: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #7: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #7: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 #8: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #8: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #8: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #8: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 1 lock held by klogd/5181: #0: ffff888037b4e108 (&u->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #0: ffff888037b4e108 (&u->lock){+.+.}-{3:3}, at: unix_dgram_sendmsg+0x907/0x18d0 net/unix/af_unix.c:2178 2 locks held by dhcpcd/5487: #0: ffff888032660928 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: netlink_dump+0xe2/0xe10 net/netlink/af_netlink.c:2267 #1: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6862 2 locks held by getty/5582: #0: ffff88803752d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90003cbe2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211 2 locks held by udevd/5819: #0: ffff88801b2fb238 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x9e/0x650 fs/kernfs/dir.c:1218 #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline] #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: kernfs_root+0x1c/0x230 fs/kernfs/kernfs-internal.h:74 1 lock held by udevd/5833: #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1181 [inline] #0: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa6/0x2550 arch/x86/kernel/unwind_orc.c:495 2 locks held by udevd/5839: #0: ffff8880382be480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493 #1: ffff8880381b3f48 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1074 [inline] #1: ffff8880381b3f48 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3787 [inline] #1: ffff8880381b3f48 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: __start_renaming+0x148/0x410 fs/namei.c:3880 2 locks held by udevd/6341: #0: ffff888033a471a0 (&group->mark_mutex){+.+.}-{4:4}, at: fsnotify_group_lock include/linux/fsnotify_backend.h:289 [inline] #0: ffff888033a471a0 (&group->mark_mutex){+.+.}-{4:4}, at: inotify_update_watch fs/notify/inotify/inotify_user.c:643 [inline] #0: ffff888033a471a0 (&group->mark_mutex){+.+.}-{4:4}, at: __do_sys_inotify_add_watch fs/notify/inotify/inotify_user.c:782 [inline] #0: ffff888033a471a0 (&group->mark_mutex){+.+.}-{4:4}, at: __se_sys_inotify_add_watch+0x36a/0xf60 fs/notify/inotify/inotify_user.c:730 #1: ffff8880b863a288 ((lock)){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #1: ffff8880b863a288 ((lock)){+.+.}-{3:3}, at: __radix_tree_preload+0x141/0x870 lib/radix-tree.c:334 1 lock held by syz-executor/6909: #0: ffff8880325100d0 (&type->s_umount_key#78){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff8880325100d0 (&type->s_umount_key#78){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline] #0: ffff8880325100d0 (&type->s_umount_key#78){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508 3 locks held by syz.4.1166/9178: #0: ffff888041536928 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1261 #1: ffff88803adba480 (sb_writers#3){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2731 [inline] #1: ffff88803adba480 (sb_writers#3){.+.+}-{0:0}, at: vfs_writev+0x2b0/0x9a0 fs/read_write.c:1057 #2: ffff8880325100d0 (&type->s_umount_key#78){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline] #2: ffff8880325100d0 (&type->s_umount_key#78){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122 1 lock held by syz-executor/10329: #0: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #0: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #0: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 2 locks held by syz-executor/10384: #0: ffffffff8fd0efa8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8fd0efa8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8fd0efa8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f79f5f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107 4 locks held by syz.0.1581/10531: #0: ffff88803d31deb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:592 [inline] #0: ffff88803d31deb0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x194/0x9e0 mm/mmap.c:1284 #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #1: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290 #2: ffff88805cbe9658 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #2: ffff88805cbe9658 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404 #3: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #3: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline] #3: ffffffff8e3c80c0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57 2 locks held by syz.9.1582/10533: #0: ffffffff8e5059f8 (srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:187 [inline] #0: ffffffff8e5059f8 (srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:294 [inline] #0: ffffffff8e5059f8 (srcu){.+.+}-{0:0}, at: mn_hlist_release mm/mmu_notifier.c:337 [inline] #0: ffffffff8e5059f8 (srcu){.+.+}-{0:0}, at: __mmu_notifier_release+0x4a8/0x7a0 mm/mmu_notifier.c:385 #1: ffff88802a29a468 (&subscriptions->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #1: ffff88802a29a468 (&subscriptions->lock){+.+.}-{3:3}, at: mn_hlist_release mm/mmu_notifier.c:349 [inline] #1: ffff88802a29a468 (&subscriptions->lock){+.+.}-{3:3}, at: __mmu_notifier_release+0x588/0x7a0 mm/mmu_notifier.c:385 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 17 Comm: pr/legacy Tainted: G L syzkaller #0 PREEMPT_{RT,(full)} Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:401 Code: e8 be 60 7e fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 6f be e7 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 ca 89 fd 05 cc 44 89 f9 80 e1 07 RSP: 0018:ffffc900001679d0 EFLAGS: 00000202 RAX: 1ffffffff3404c00 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffffff9a026490 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff85468d90 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff9a026200 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125b6b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2e21cff8 CR3: 0000000059ba4000 CR4: 00000000003526f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1970 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3207 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3272 [inline] serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3357 console_emit_next_record kernel/printk/printk.c:3163 [inline] console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3269 legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245