INFO: task syz.7.2055:12515 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.7.2055 state:D stack:25192 pid:12515 tgid:12514 ppid:11932 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5352 [inline]
__schedule+0x1665/0x5590 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7047 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7062
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7119
rwsem_down_write_slowpath+0x883/0x1080 kernel/locking/rwsem.c:1215
__down_write_common kernel/locking/rwsem.c:1347 [inline]
__down_write kernel/locking/rwsem.c:1356 [inline]
down_write+0x1bc/0x200 kernel/locking/rwsem.c:1626
mmap_write_lock include/linux/mmap_lock.h:536 [inline]
userfaultfd_register fs/userfaultfd.c:1317 [inline]
userfaultfd_ioctl+0x21fb/0x4c70 fs/userfaultfd.c:2050
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff75d79c799
RSP: 002b:00007ff75e5f9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ff75da15fa0 RCX: 00007ff75d79c799
RDX: 0000200000000080 RSI: 00000000c020aa00 RDI: 0000000000000008
RBP: 00007ff75d832c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff75da16038 R14: 00007ff75da15fa0 R15: 00007ffdb287f9e8
Showing all locks held in the system:
1 lock held by rcu_exp_gp_kthr/18:
#0: ffff8880b843ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x31/0x150 kernel/sched/core.c:647
1 lock held by khungtaskd/31:
#0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8eb5d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
6 locks held by kworker/1:2/805:
#0: ffff8880222da140 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc90004b17c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffff88802b233190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#2: ffff88802b233190 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff888079457190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#3: ffff888079457190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
#4: ffff888076bfc158 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#4: ffff888076bfc158 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
#5: ffffffff8ff5d1c0 (register_mutex#6){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#5: ffffffff8ff5d1c0 (register_mutex#6){+.+.}-{4:4}, at: usb_audio_probe+0x82e/0x2330 sound/usb/card.c:946
2 locks held by getty/5595:
#0: ffff888037a570a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by kworker/1:4/5875:
#0: ffff8880222da140 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc900045b7c40 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffff88802b45b190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#2: ffff88802b45b190 (&dev->mutex){....}-{4:4}, at: hub_event+0x17f/0x4f30 drivers/usb/core/hub.c:5899
#3: ffff88807950b190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline]
#3: ffff88807950b190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x450 drivers/base/dd.c:1008
6 locks held by kworker/u9:3/7732:
#0: ffff88802af8b140 ((wq_completion)hci4){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc9000fdefc40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffff888067fc0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d3/0x400 net/bluetooth/hci_sync.c:331
#3: ffff888067fc00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0xa6f/0x1190 net/bluetooth/hci_sync.c:5734
#4: ffffffff901836e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline]
#4: ffffffff901836e0 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_failed+0x165/0x340 net/bluetooth/hci_conn.c:1342
#5: ffff88804d22c2f0 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1751
4 locks held by udevd/11936:
#0: ffff88804c2431b8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe10 fs/seq_file.c:183
#1: ffff888037062880 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420 fs/kernfs/file.c:172
#2: ffff888058011b48 (kn->active#27){++++}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff888058011b48 (kn->active#27){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420 fs/kernfs/file.c:173
#3: ffff88807950b190 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:946 [inline]
#3: ffff88807950b190 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
1 lock held by syz.7.2055/12515:
#0: ffff88801d38dab8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock include/linux/mmap_lock.h:536 [inline]
#0: ffff88801d38dab8 (&mm->mmap_lock){++++}-{4:4}, at: userfaultfd_register fs/userfaultfd.c:1317 [inline]
#0: ffff88801d38dab8 (&mm->mmap_lock){++++}-{4:4}, at: userfaultfd_ioctl+0x21fb/0x4c70 fs/userfaultfd.c:2050
3 locks held by kworker/u8:12/15663:
#0: ffff88813fe44140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc9000561fc40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffffffff8fff6340 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313
3 locks held by kworker/u8:13/15665:
3 locks held by kworker/u8:14/15667:
#0: ffff88813fe44140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261
#1: ffffc9000565fc40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262
#2: ffff88804f830780 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6443 [inline]
#2: ffff88804f830780 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x4a0 net/wireless/core.c:425
1 lock held by syz.6.3138/15919:
#0: ffffffff8eb638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#0: ffffffff8eb638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961
1 lock held by syz.8.3141/15944:
#0: ffffffff8fff6340 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8fff6340 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3436
2 locks held by syz.2.3146/15968:
#0: ffffffff8fff6340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8fff6340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8fff6340 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dellink+0x42a/0x820 net/core/rtnetlink.c:3562
#1: ffffffff8eb638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8eb638e8 (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 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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+0x1002/0x1060 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
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: 5816 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:switch_fpu_return+0x0/0x1e0 arch/x86/kernel/fpu/core.c:881
Code: 8b 25 88 65 e1 0c e9 04 fe ff ff e8 ba f7 59 00 e9 f4 fd ff ff 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <0f> 1f 40 d6 55 41 57 41 56 41 55 41 54 53 49 bc 00 00 00 00 00 fc
RSP: 0018:ffffc90003aa7ed0 EFLAGS: 00000006
RAX: ffffffff816d0165 RBX: 0000000000080000 RCX: ffff888036991e80
RDX: 0000000000000000 RSI: 0000000000080000 RDI: 0000000000080000
RBP: ffffc90003aa7f38 R08: ffff888036991e87 R09: 1ffff11006d323d0
R10: dffffc0000000000 R11: ffffed1006d323d1 R12: 0000000000000000
R13: 0000000000000000 R14: ffffc90003aa7f48 R15: ffff888036991e80
FS: 0000555571e08540(0000) GS:ffff888124de0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f729877dfe0 CR3: 000000002b492000 CR4: 00000000003526f0
Call Trace:
arch_exit_to_user_mode_prepare+0x9d/0xc0 arch/x86/include/asm/entry-common.h:66
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:241 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:269 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x1ce/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f54e9957917
Code: 48 89 fa 4c 89 df e8 a8 56 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffd7635c4f0 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6
RAX: 0000000000000000 RBX: 0000555571e08540 RCX: 00007f54e9957917
RDX: 00007ffd7635c530 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffd7635ca10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000004
R13: 00007ffd7635c56c R14: 00007ffd7635c600 R15: 0000000000000000