INFO: task syz.5.147:6791 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.147 state:D stack:28744 pid:6791 tgid:6774 ppid:6058 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5257 [inline] __schedule+0x14bc/0x5030 kernel/sched/core.c:6864 __schedule_loop kernel/sched/core.c:6946 [inline] schedule+0x165/0x360 kernel/sched/core.c:6961 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7018 rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185 __down_write_common kernel/locking/rwsem.c:1317 [inline] __down_write kernel/locking/rwsem.c:1326 [inline] down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591 inode_lock include/linux/fs.h:1027 [inline] open_last_lookups fs/namei.c:4506 [inline] path_openat+0xabf/0x3d90 fs/namei.c:4753 do_filp_open+0x1fa/0x410 fs/namei.c:4783 do_sys_openat2+0x121/0x1c0 fs/open.c:1432 do_sys_open fs/open.c:1447 [inline] __do_sys_creat fs/open.c:1525 [inline] __se_sys_creat fs/open.c:1519 [inline] __x64_sys_creat+0x8f/0xc0 fs/open.c:1519 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8f5fb8f749 RSP: 002b:00007f8f6097c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000055 RAX: ffffffffffffffda RBX: 00007f8f5fde6090 RCX: 00007f8f5fb8f749 RDX: 0000000000000000 RSI: 071283578ac7c5cd RDI: 0000200000000180 RBP: 00007f8f5fc13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8f5fde6128 R14: 00007f8f5fde6090 R15: 00007fff1f1c40a8 Showing all locks held in the system: 4 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8df3d980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 8 locks held by kworker/u8:4/71: 2 locks held by getty/5583: #0: ffff8880345550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 3 locks held by kworker/0:7/5968: #0: ffff88813fe55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x841/0x15e0 kernel/workqueue.c:3236 #1: ffffc90005037b80 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x868/0x15e0 kernel/workqueue.c:3237 #2: ffff88805997c240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1f7/0x3b0 drivers/net/netdevsim/fib.c:1490 2 locks held by syz-executor/6720: #0: ffff8880274140e0 (&type->s_umount_key#69){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff8880274140e0 (&type->s_umount_key#69){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff8880274140e0 (&type->s_umount_key#69){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8e380788 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 4 locks held by kworker/u8:16/6727: #0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x841/0x15e0 kernel/workqueue.c:3236 #1: ffffc900035c7b80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x868/0x15e0 kernel/workqueue.c:3237 #2: ffffffff8f2daf08 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303 #3: ffffffff8df43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #3: ffffffff8df43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 3 locks held by syz.5.147/6777: 2 locks held by syz.5.147/6791: #0: ffff888059698420 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:509 #1: ffff88804f450ae0 (&type->i_mutex_dir_key#12){++++}-{4:4}, at: inode_lock include/linux/fs.h:1027 [inline] #1: ffff88804f450ae0 (&type->i_mutex_dir_key#12){++++}-{4:4}, at: open_last_lookups fs/namei.c:4506 [inline] #1: ffff88804f450ae0 (&type->i_mutex_dir_key#12){++++}-{4:4}, at: path_openat+0xabf/0x3d90 fs/namei.c:4753 3 locks held by syz.6.168/6902: 2 locks held by syz-executor/7857: #0: ffff88807d8100e0 (&type->s_umount_key#69){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline] #0: ffff88807d8100e0 (&type->s_umount_key#69){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline] #0: ffff88807d8100e0 (&type->s_umount_key#69){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506 #1: ffffffff8e380788 (jfs_log_mutex){+.+.}-{4:4}, at: lmLogClose+0xb4/0x520 fs/jfs/jfs_logmgr.c:1443 3 locks held by syz-executor/8039: #0: ffffffff8f340eb0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8f340cc8 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffffffff8f340cc8 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffffffff8f340cc8 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0x10d/0x790 net/netlink/genetlink.c:1209 #2: ffffffff8f2daf08 (rtnl_mutex){+.+.}-{4:4}, at: ieee80211_register_hw+0x34df/0x4110 net/mac80211/main.c:1599 3 locks held by kworker/0:11/8438: #0: ffff88813fe55948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x841/0x15e0 kernel/workqueue.c:3236 #1: ffffc900044cfb80 ((fqdir_free_work).work){+.+.}-{0:0}, at: process_one_work+0x868/0x15e0 kernel/workqueue.c:3237 #2: ffffffff8df43300 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820 2 locks held by syz.2.429/8628: #0: ffff8880319fb070 (&fc->uapi_mutex){+.+.}-{4:4}, at: __do_sys_fsconfig fs/fsopen.c:471 [inline] #0: ffff8880319fb070 (&fc->uapi_mutex){+.+.}-{4:4}, at: __se_sys_fsconfig+0x758/0x8d0 fs/fsopen.c:350 #1: ffffffff8df43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #1: ffffffff8df43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 ============================================= 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 10/25/2025 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:160 [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:346 [inline] watchdog+0xfb5/0x1000 kernel/hung_task.c:515 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6727 Comm: kworker/u8:16 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:io_serial_out+0x7c/0xc0 drivers/tty/serial/8250/8250_port.c:407 Code: 2d a5 fc 44 89 f9 d3 e5 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 6c c9 0b fd 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d e9 c7 13 42 06 cc 44 89 f9 80 e1 07 38 c1 RSP: 0018:ffffc900035c71b0 EFLAGS: 00000002 RAX: 0000000000000030 RBX: 0000000000000030 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 00000000000003f8 R08: ffff888024a00237 R09: 1ffff11004940046 R10: dffffc0000000000 R11: ffffffff851cab90 R12: dffffc0000000000 R13: ffffffff9985a9a9 R14: ffffffff99b6f0c0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125eba000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1163d6ae9c CR3: 0000000076770000 CR4: 00000000003526f0 Call Trace: serial_port_out include/linux/serial_core.h:811 [inline] serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3192 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline] serial8250_console_write+0x1410/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record kernel/printk/printk.c:3215 [inline] console_flush_all+0x745/0xb60 kernel/printk/printk.c:3289 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0xbb/0x190 kernel/printk/printk.c:3359 vprintk_emit+0x4d3/0x5d0 kernel/printk/printk.c:2426 _printk+0xcf/0x120 kernel/printk/printk.c:2451 ieee80211_sta_create_ibss+0x275/0x480 net/mac80211/ibss.c:1309 ieee80211_sta_find_ibss net/mac80211/ibss.c:1445 [inline] ieee80211_ibss_work+0xdb6/0x1060 net/mac80211/ibss.c:1666 cfg80211_wiphy_work+0x2ab/0x470 net/wireless/core.c:438 process_one_work+0x93a/0x15e0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246