INFO: task syz.0.17:6442 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:28200 pid:6442  tgid:6440  ppid:6367   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x17b4/0x5680 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7282
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7339
 __mutex_lock_common kernel/locking/mutex.c:712 [inline]
 __mutex_lock+0x7f5/0x1550 kernel/locking/mutex.c:806
 bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
 __lookup_slow+0x2b7/0x410 fs/namei.c:1915
 lookup_slow+0x53/0x70 fs/namei.c:1932
 walk_component fs/namei.c:2278 [inline]
 link_path_walk+0xd1e/0x18d0 fs/namei.c:2652
 path_parentat fs/namei.c:2856 [inline]
 __filename_parentat+0x27f/0x6f0 fs/namei.c:2880
 filename_parentat fs/namei.c:2898 [inline]
 filename_create+0xd9/0x370 fs/namei.c:4931
 filename_mkdirat+0xd2/0x510 fs/namei.c:5287
 __do_sys_mkdirat fs/namei.c:5315 [inline]
 __se_sys_mkdirat+0x35/0x150 fs/namei.c:5312
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9ec939a379
RSP: 002b:00007f9eca2a5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f9ec95f6090 RCX: 00007f9ec939a379
RDX: 00000000000001ff RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f9ec942dd68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9ec95f6128 R14: 00007f9ec95f6090 R15: 00007ffd7b52bcb8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5587:
 #0: ffff888038aa00a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
3 locks held by syz.0.17/6441:
2 locks held by syz.0.17/6442:
 #0: ffff88805db17b18 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff88805db17b18 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff8880381f84d0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
2 locks held by syz.1.18/6466:
2 locks held by syz.1.18/6467:
 #0: ffff88805db175e0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff88805db175e0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff88805f9456d0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
3 locks held by syz.2.19/6489:
2 locks held by syz.2.19/6490:
 #0: ffff888078243b18 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff888078243b18 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff88807b3782d0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
2 locks held by syz.3.20/6518:
2 locks held by syz.3.20/6519:
 #0: ffff88805db170a8 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff88805db170a8 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff88807e1eced0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
3 locks held by syz.4.21/6548:
2 locks held by syz.4.21/6549:
 #0: ffff88805db16b70 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff88805db16b70 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff88802ba31ed0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
2 locks held by syz.5.22/6581:
2 locks held by syz.5.22/6582:
 #0: ffff8880782435e0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff8880782435e0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff888027fa90d0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
2 locks held by syz.6.23/6621:
2 locks held by syz.6.23/6622:
 #0: ffff88805db16638 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:1044 [inline]
 #0: ffff88805db16638 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1931
 #1: ffff88801b3caed0 (&info->bfs_lock){+.+.}-{4:4}, at: bfs_lookup+0xe3/0x1d0 fs/bfs/dir.c:143
3 locks held by syz-executor/6624:
 #0: ffffffff8fde1640 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #0: ffffffff8fde1640 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #0: ffffffff8fde1640 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x883/0x1bb0 net/core/rtnetlink.c:4107
 #1: ffff88802b3d5550 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50
 #2: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
 #2: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:961

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
 <TASK>
 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
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6624 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:__bfs kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline]
RIP: 0010:validate_chain kernel/locking/lockdep.c:3908 [inline]
RIP: 0010:__lock_acquire+0x1968/0x2cf0 kernel/locking/lockdep.c:5237
Code: 89 c1 81 e1 ff 0f 00 00 89 0d 98 1f a7 14 2b 05 8e 1f a7 14 25 ff 0f 00 00 39 05 4f 1f a6 12 73 06 89 05 47 1f a6 12 48 8b 02 <48> 89 df 4c 39 e8 0f 84 2c fe ff ff 4c 89 60 30 48 8b 00 4c 39 e8
RSP: 0018:ffffc90003a866a0 EFLAGS: 00000002
RAX: ffffffff96d98ea8 RBX: 00000000000003dd RCX: 000000000000003c
RDX: ffffffff96ce5de8 RSI: ffff8880322dab40 RDI: 00000000000003dd
RBP: 17079689119d43f8 R08: ffffc90003a86668 R09: 0000000000000020
R10: dffffc0000000000 R11: ffffffff81a229d0 R12: ffffffff96d9bc98
R13: ffffffff93eaffd8 R14: ffff8880322d9ec0 R15: 000000000000003b
FS:  0000555588cde500(0000) GS:ffff88812521e000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffe3869640 CR3: 0000000034a0c000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 lock_acquire+0x106/0x350 kernel/locking/lockdep.c:5868
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
 _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
 uart_port_lock_irqsave include/linux/serial_core.h:717 [inline]
 serial8250_console_write+0x150/0x1ba0 drivers/tty/serial/8250/8250_port.c:3316
 console_emit_next_record kernel/printk/printk.c:3183 [inline]
 console_flush_one_record kernel/printk/printk.c:3269 [inline]
 console_flush_all+0x718/0xb20 kernel/printk/printk.c:3343
 __console_flush_and_unlock kernel/printk/printk.c:3373 [inline]
 console_unlock+0xd1/0x1c0 kernel/printk/printk.c:3413
 vprintk_emit+0x485/0x560 kernel/printk/printk.c:2479
 dev_vprintk_emit+0x355/0x420 drivers/base/core.c:4930
 dev_printk_emit+0xee/0x140 drivers/base/core.c:4941
 _dev_printk+0x127/0x180 drivers/base/core.c:4970
 ieee80211_init_rate_ctrl_alg+0x55d/0x5d0 net/mac80211/rate.c:1026
 ieee80211_register_hw+0x38b2/0x4a70 net/mac80211/main.c:1559
 mac80211_hwsim_new_radio+0x3334/0x5ba0 drivers/net/wireless/virtual/mac80211_hwsim.c:6019
 hwsim_new_radio_nl+0xf6a/0x1c00 drivers/net/wireless/virtual/mac80211_hwsim.c:6726
 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114
 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
 genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x75c/0x8e0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:787 [inline]
 __sock_sendmsg net/socket.c:802 [inline]
 __sys_sendto+0x672/0x710 net/socket.c:2265
 __do_sys_sendto net/socket.c:2272 [inline]
 __se_sys_sendto net/socket.c:2268 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2268
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f638935ac4e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007ffdc611bec8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000555588cde500 RCX: 00007f638935ac4e
RDX: 0000000000000024 RSI: 00007f638a124670 RDI: 0000000000000003
RBP: 0000000000000001 R08: 00007ffdc611bf44 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 0000000000000000 R14: 00007f638a124670 R15: 0000000000000000
 </TASK>