INFO: task syz-executor:4251 blocked for more than 144 seconds. Not tainted 6.1.131-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:20984 pid:4251 ppid:1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5243 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6560 schedule+0xbf/0x180 kernel/sched/core.c:6636 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 deactivate_super+0xa9/0xe0 fs/super.c:362 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f9573b8e497 RSP: 002b:00007ffeec19b258 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f9573c0e08c RCX: 00007f9573b8e497 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffeec19b310 RBP: 00007ffeec19b310 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffeec19c3a0 R13: 00007f9573c0e08c R14: 000000000004120b R15: 00007ffeec19c3e0 Showing all locks held in the system: 3 locks held by kworker/u4:1/11: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32e890 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32f090 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/27: #0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32e6c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 2 locks held by getty/4003: #0: ffff888031051098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000325e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x54a/0x1620 drivers/tty/n_tty.c:2198 1 lock held by syz-executor/4251: #0: ffff888076bbc0e0 (&type->s_umount_key#32){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:362 3 locks held by kworker/0:5/4295: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003ff7d20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffff888053e2f240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x316/0x41f0 drivers/net/netdevsim/fib.c:1491 2 locks held by kworker/1:4/4296: #0: ffff888017c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90004007d20 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 3 locks held by kworker/1:6/4299: #0: ffff888017c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90004037d20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffff888027b32240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x316/0x41f0 drivers/net/netdevsim/fib.c:1491 3 locks held by kworker/1:10/4674: #0: ffff888030294538 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90003577d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16e0 net/ipv6/addrconf.c:4134 5 locks held by kworker/u4:26/5810: 5 locks held by kworker/u4:41/5827: #0: ffff888017e16938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #1: ffffc90004d17d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x806/0x1260 kernel/workqueue.c:2267 #2: ffffffff8e543a50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xd20 net/core/net_namespace.c:594 #3: ffff888055c242f8 (&devlink->lock_key#12){+.+.}-{3:3}, at: devlink_pernet_pre_exit+0x132/0x2f0 net/devlink/leftover.c:12500 #4: ffffffff8e5505a8 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x3a/0x140 drivers/net/netdevsim/netdev.c:381 2 locks held by ext4lazyinit/7985: 1 lock held by syz.2.1439/8782: #0: ffff888076bbc0e0 (&type->s_umount_key#32){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 1 lock held by syz.9.1895/10004: #0: ffff888076bbc0e0 (&type->s_umount_key#32){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:755 1 lock held by syz-executor/10294: #0: ffffffff8d333cf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] #0: ffffffff8d333cf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x360/0x930 kernel/rcu/tree_exp.h:962 1 lock held by syz.2.1961/10359: #0: ffffffff8d333cf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #0: ffffffff8d333cf8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4f0/0x930 kernel/rcu/tree_exp.h:962 2 locks held by syz.5.2018/10363: #0: ffff88807caf90b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close net/bluetooth/hci_core.c:507 [inline] #0: ffff88807caf90b8 (&hdev->req_lock){+.+.}-{3:3}, at: hci_unregister_dev+0x1ff/0x500 net/bluetooth/hci_core.c:2706 #1: ffff88807caf8078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x48d/0xfc0 net/bluetooth/hci_sync.c:5165 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.1.131-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+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1ca/0x430 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf88/0xfd0 kernel/hung_task.c:377 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3611 Comm: klogd Not tainted 6.1.131-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:kasan_check_range+0x1/0x290 mm/kasan/generic.c:188 Code: 01 c6 48 89 c7 e8 4f 35 d0 08 31 c0 c3 0f 0b b8 ea ff ff ff c3 0f 0b b8 ea ff ff ff c3 cc cc cc cc cc cc cc cc cc cc cc cc 55 <41> 57 41 56 53 b0 01 48 85 f6 0f 84 9a 01 00 00 48 89 fd 48 01 f5 RSP: 0018:ffffc90003257630 EFLAGS: 00000246 RAX: ffffffff8aac02af RBX: 0000000000000018 RCX: ffffffff8aac02be RDX: 0000000000000001 RSI: 0000000000000018 RDI: ffffc900032576e0 RBP: ffffc900032576e0 R08: ffffffff8aabb9bb R09: ffffffff8aabb580 R10: 0000000000000012 R11: ffff88807d133b80 R12: ffff0a00ffffff0f R13: dffffc0000000000 R14: 0000000000000000 R15: ffffc90003257ac1 FS: 00007f309e5ba380(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562569192250 CR3: 000000007e5d6000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: memset+0x1f/0x40 mm/kasan/shadow.c:44 number+0x9e/0xf80 lib/vsprintf.c:458 vsnprintf+0x1361/0x1c70 lib/vsprintf.c:2871 sprintf+0xd6/0x120 lib/vsprintf.c:3009 print_syslog kernel/printk/printk.c:1267 [inline] info_print_prefix+0xda/0x300 kernel/printk/printk.c:1297 record_print_text+0x142/0x430 kernel/printk/printk.c:1349 syslog_print+0x3d8/0x620 kernel/printk/printk.c:1560 do_syslog+0x819/0x910 kernel/printk/printk.c:1679 __do_sys_syslog kernel/printk/printk.c:1771 [inline] __se_sys_syslog kernel/printk/printk.c:1769 [inline] __x64_sys_syslog+0x78/0x90 kernel/printk/printk.c:1769 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f309e71bfa7 Code: 73 01 c3 48 8b 0d 81 ce 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 51 ce 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007ffef0523768 EFLAGS: 00000206 ORIG_RAX: 0000000000000067 RAX: ffffffffffffffda RBX: 00007f309e8ba4a0 RCX: 00007f309e71bfa7 RDX: 00000000000003ff RSI: 00007f309e8ba4a0 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000003 R09: 29970c47c691a2af R10: 0000000000004000 R11: 0000000000000206 R12: 00007f309e8ba4a0 R13: 00007f309e8aa212 R14: 00007f309e8ba51e R15: 00007f309e8ba51e