INFO: task syz-executor:5823 blocked for more than 143 seconds. Not tainted 6.15.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:21824 pid:5823 tgid:5823 ppid:1 task_flags:0x400140 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 io_schedule+0x81/0xe0 kernel/sched/core.c:7742 folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317 __folio_lock mm/filemap.c:1664 [inline] folio_lock include/linux/pagemap.h:1137 [inline] __filemap_get_folio+0x139/0xaf0 mm/filemap.c:1917 truncate_inode_pages_range+0x3ed/0xda0 mm/truncate.c:384 evict+0x517/0x9c0 fs/inode.c:812 dispose_list fs/inode.c:852 [inline] evict_inodes+0x636/0x6c0 fs/inode.c:906 generic_shutdown_super+0x9a/0x2c0 fs/super.c:627 kill_block_super+0x44/0x90 fs/super.c:1710 deactivate_locked_super+0xbc/0x130 fs/super.c:473 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1431 task_work_run+0x1d4/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5f95d8fc97 RSP: 002b:00007ffddc47d6d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f5f95e1089d RCX: 00007f5f95d8fc97 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffddc47d790 RBP: 00007ffddc47d790 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffddc47e820 R13: 00007f5f95e1089d R14: 000000000002bfdf R15: 00007ffddc47e860 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5584: #0: ffff88814d2f30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036e32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5823: #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505 1 lock held by syz-executor/5824: #0: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #0: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 8 locks held by kworker/0:3/5834: 5 locks held by kworker/0:5/5893: #0: ffff888020ad0548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888020ad0548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90002e2fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90002e2fc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff888144f7e198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #2: ffff888144f7e198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5859 #3: ffff8880792b0198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #3: ffff8880792b0198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004 #4: ffff888028f33160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff888028f33160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400 drivers/base/dd.c:1004 3 locks held by udevd/6041: 1 lock held by syz.1.349/7287: #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.1.349/7288: #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.1.349/7289: #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.1.349/7291: #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz.1.349/7293: #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline] #0: ffff88805237e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120 1 lock held by syz-executor/7589: #0: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #0: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 2 locks held by kworker/u8:15/7599: 3 locks held by dhcpcd-run-hook/8710: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 5834 Comm: kworker/0:3 Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: usb_hub_wq hub_event RIP: 0010:___neigh_create+0x1574/0x2260 net/core/neighbour.c:-1 Code: 00 00 00 45 2b 37 bf 20 00 00 00 44 89 f6 e8 43 03 7b f8 41 83 fe 1f 0f 87 e9 0a 00 00 e8 f4 fe 7a f8 4c 8b bc 24 c0 00 00 00 <48> 8b 44 24 68 80 3c 28 00 74 08 4c 89 ff e8 39 f9 dc f8 4d 8b 3f RSP: 0018:ffffc90000007658 EFLAGS: 00000246 RAX: ffffffff8944f2dc RBX: 00000000ff8e358f RCX: ffff8880314a5a00 RDX: 0000000000000100 RSI: 0000000000000015 RDI: 0000000000000020 RBP: dffffc0000000000 R08: ffffffff8f409fbb R09: 1ffffffff1e813f7 R10: dffffc0000000000 R11: ffffffff8a11fb10 R12: 1ffff1100672c4b1 R13: ffffffff8f409ca0 R14: 0000000000000015 R15: ffff88804a21c828 FS: 0000000000000000(0000) GS:ffff8881260c2000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc425180178 CR3: 000000007704c000 CR4: 0000000000350ef0 Call Trace: ip6_finish_output2+0xb4d/0x16a0 net/ipv6/ip6_output.c:132 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xb47/0x1400 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4041 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_flush_all+0x7f7/0xc40 kernel/printk/printk.c:3227 Code: 48 21 c3 0f 85 e9 01 00 00 e8 25 b5 1e 00 48 8b 5c 24 20 4d 85 f6 75 07 e8 16 b5 1e 00 eb 06 e8 0f b5 1e 00 fb 48 8b 44 24 28 <42> 80 3c 20 00 74 08 48 89 df e8 5a af 80 00 48 8b 1b 48 8b 44 24 RSP: 0018:ffffc900038f7060 EFLAGS: 00000283 RAX: 1ffffffff1cf4afb RBX: ffffffff8e7a57d8 RCX: 0000000000100000 RDX: ffffc9001b5da000 RSI: 0000000000029bb5 RDI: 0000000000029bb6 RBP: ffffc900038f71b0 R08: ffffffff8f7f3377 R09: 1ffffffff1efe66e R10: dffffc0000000000 R11: fffffbfff1efe66f R12: dffffc0000000000 R13: 0000000000000001 R14: 0000000000000200 R15: ffffffff8e7a5780 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline] console_unlock+0xc4/0x270 kernel/printk/printk.c:3325 vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450 dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4917 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4928 _dev_info+0x10a/0x160 drivers/base/core.c:4986 announce_device+0x117/0x2c0 drivers/usb/core/hub.c:2381 usb_new_device+0x4ef/0x16c0 drivers/usb/core/hub.c:2644 hub_port_connect drivers/usb/core/hub.c:5531 [inline] hub_port_connect_change drivers/usb/core/hub.c:5671 [inline] port_event drivers/usb/core/hub.c:5831 [inline] hub_event+0x2941/0x4a00 drivers/usb/core/hub.c:5913 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4e/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245