syzbot


INFO: task hung in __lru_add_drain_all (3)

Status: upstream: reported on 2026/03/10 22:55
Reported-by: syzbot+7071e1cb807dc51207d5@syzkaller.appspotmail.com
First crash: 51d, last: 3d13h
Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 INFO: task hung in __lru_add_drain_all (3) 1 1 52m 51m 0/3 upstream: reported on 2026/05/01 08:27
linux-6.6 INFO: task hung in __lru_add_drain_all 1 1 178d 178d 0/2 auto-obsoleted due to no activity on 2026/02/12 06:31
linux-6.1 INFO: task hung in __lru_add_drain_all (2) 1 1 333d 333d 0/3 auto-obsoleted due to no activity on 2025/09/09 22:30
linux-5.15 INFO: task hung in __lru_add_drain_all 1 1 1104d 1104d 0/3 auto-obsoleted due to no activity on 2023/08/21 02:18
linux-6.1 INFO: task hung in __lru_add_drain_all 1 1 713d 713d 0/3 auto-obsoleted due to no activity on 2024/08/25 20:43
upstream INFO: task hung in __lru_add_drain_all (2) mm 1 syz error 272 375d 713d 0/29 auto-obsoleted due to no activity on 2025/06/29 18:01
upstream INFO: task hung in __lru_add_drain_all net 1 C done error 71 900d 1701d 0/29 auto-obsoleted due to no activity on 2024/02/20 10:46
linux-5.15 INFO: task hung in __lru_add_drain_all (2) 1 1 644d 644d 0/3 auto-obsoleted due to no activity on 2024/11/03 03:56
android-6-12 INFO: task hung in __lru_add_drain_all 1 1 178d 178d 0/1 auto-obsoleted due to no activity on 2026/02/01 19:21

Sample crash report:
INFO: task khugepaged:35 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:khugepaged      state:D stack:28784 pid:35    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138
 __flush_work+0x952/0xae0 kernel/workqueue.c:3076
 __lru_add_drain_all+0x6a0/0x800 mm/swap.c:910
 khugepaged_do_scan mm/khugepaged.c:2453 [inline]
 khugepaged+0x183/0x19a0 mm/khugepaged.c:2522
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task kworker/1:5:4310 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:5     state:D
 stack:22448 pid:4310  ppid:2      flags:0x00004000
Workqueue: events_power_efficient crda_timeout_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
 crda_timeout_work+0x11/0x50 net/wireless/reg.c:539
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task kworker/u4:9:4592 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:9    state:D stack:26224 pid:4592  ppid:2      flags:0x00004000
Workqueue: events_unbound fsnotify_mark_destroy_workfn
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138
 __synchronize_srcu+0x2b9/0x350 kernel/rcu/srcutree.c:1243
 fsnotify_mark_destroy_workfn+0x106/0x2f0 fs/notify/mark.c:924
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task kworker/u4:10:4627 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:10   state:D stack:26384 pid:4627  ppid:2      flags:0x00004000
Workqueue: events_unbound fsnotify_connector_destroy_workfn
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138
 __synchronize_srcu+0x2b9/0x350 kernel/rcu/srcutree.c:1243
 fsnotify_connector_destroy_workfn+0x40/0xa0 fs/notify/mark.c:234
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
INFO: task syz.2.139:4838 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.139       state:D stack:26736 pid:4838  ppid:4278   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 synchronize_rcu_expedited+0x6e6/0x890 kernel/rcu/tree_exp.h:977
 netif_napi_del include/linux/netdevice.h:2645 [inline]
 tun_napi_del drivers/net/tun.c:291 [inline]
 __tun_detach+0x198/0x1500 drivers/net/tun.c:645
 tun_detach drivers/net/tun.c:701 [inline]
 tun_chr_close+0x109/0x1b0 drivers/net/tun.c:3492
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0b4399cdd9
RSP: 002b:00007f0b447ca028 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007f0b43c15fa0 RCX: 00007f0b4399cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f0b43a32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b43c16038 R14: 00007f0b43c15fa0 R15: 00007fff7fb9baa8
 </TASK>
INFO: task syz.2.139:4840 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.139       state:D stack:27632 pid:4840  ppid:4278   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
 register_nexthop_notifier+0x84/0x240 net/ipv4/nexthop.c:3619
 ops_init+0x355/0x5f0 net/core/net_namespace.c:138
 setup_net+0x4f2/0xbd0 net/core/net_namespace.c:336
 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508
 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226
 ksys_unshare+0x503/0x8c0 kernel/fork.c:3282
 __do_sys_unshare kernel/fork.c:3353 [inline]
 __se_sys_unshare kernel/fork.c:3351 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3351
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0b4399cdd9
RSP: 002b:00007f0b447a9028 EFLAGS: 00000246
 ORIG_RAX: 0000000000000110
RAX: ffffffffffffffda RBX: 00007f0b43c16090 RCX: 00007f0b4399cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062040200
RBP: 00007f0b43a32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b43c16128 R14: 00007f0b43c16090 R15: 00007fff7fb9baa8
 </TASK>
INFO: task syz.2.139:4841 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.139       state:D stack:26384 pid:4841  ppid:4278   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
 nl80211_pre_doit+0x5b/0x930 net/wireless/nl80211.c:16369
 genl_family_rcv_msg_doit+0x1e3/0x330 net/netlink/genetlink.c:751
 genl_family_rcv_msg net/netlink/genetlink.c:833 [inline]
 genl_rcv_msg+0x604/0x790 net/netlink/genetlink.c:850
 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511
 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5be/0x970 net/socket.c:2518
 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572
 __sys_sendmsg net/socket.c:2601 [inline]
 __do_sys_sendmsg net/socket.c:2610 [inline]
 __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f0b4399cdd9
RSP: 002b:00007f0b44788028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0b43c16180 RCX: 00007f0b4399cdd9
RDX: 0000000004000000 RSI: 0000200000000200 RDI: 0000000000000006
RBP: 00007f0b43a32d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0b43c16218 R14: 00007f0b43c16180 R15: 00007fff7fb9baa8
 </TASK>
INFO: task syz.1.140:4843 blocked for more than 146 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.140       state:D stack:27856 pid:4843  ppid:4269   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
 __tun_chr_ioctl+0x3fc/0x1e60 drivers/net/tun.c:3104
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8f7419cdd9
RSP: 002b:00007f8f7512e028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8f74415fa0 RCX: 00007f8f7419cdd9
RDX: 0000200000000040 RSI: 00000000400454ca RDI: 0000000000000003
RBP: 00007f8f74232d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8f74416038 R14: 00007f8f74415fa0 R15: 00007ffccbb534c8
 </TASK>
INFO: task syz.1.140:4854 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.140       state:D stack:26864 pid:4854  ppid:4269   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
 rtnl_lock net/core/rtnetlink.c:74 [inline]
 rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 ____sys_sendmsg+0x5be/0x970 net/socket.c:2518
 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572
 __sys_sendmsg net/socket.c:2601 [inline]
 __do_sys_sendmsg net/socket.c:2610 [inline]
 __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f8f7419cdd9
RSP: 002b:00007f8f750cb028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8f74416270 RCX: 00007f8f7419cdd9
RDX: 0000000000000000 RSI: 0000200000001200 RDI: 0000000000000006
RBP: 00007f8f74232d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8f74416308 R14: 00007f8f74416270 R15: 00007ffccbb534c8
 </TASK>
INFO: task syz.4.141:4844 blocked for more than 148 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.141       state:D stack:26224 pid:4844  ppid:4268   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747
 tun_detach drivers/net/tun.c:698 [inline]
 tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1d0/0x260 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f74b819cdd9
RSP: 002b:00007ffd46003168 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f74b8417da0 RCX: 00007f74b819cdd9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f74b8417da0 R08: 0000000000000006 R09: 0000000000000000
R10: 00007f74b8417cb0 R11: 0000000000000246 R12: 000000000001e99e
R13: 00007f74b841609c R14: 000000000001e706 R15: 00007ffd46003270
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/u4:1/11:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2df70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: 
ffffffff8cb2e790 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
3 locks held by kworker/1:0/22:
 #0: ffff88802f746938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc900001c7d00 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x15/0x30 net/ipv6/addrconf.c:4672
1 lock held by khungtaskd/27:
 #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
1 lock held by khugepaged/35:
 #0: ffffffff8cbd46a8 (lock#3){+.+.}-{3:3}, at: __lru_add_drain_all+0x66/0x800 mm/swap.c:865
5 locks held by kworker/u4:4/75:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}
, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc900020afd00 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffff888054f187a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5693 [inline]
 #2: ffff888054f187a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x260 net/wireless/core.c:420
 #3: ffff88807cdecd40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1114 [inline]
 #3: ffff88807cdecd40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa8/0x10f0 net/mac80211/ibss.c:1680
 #4: ffff888054f19760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_sta_expire net/mac80211/ibss.c:1256 [inline]
 #4: ffff888054f19760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_sta_merge_ibss net/mac80211/ibss.c:1299 [inline]
 #4: ffff888054f19760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x57f/0x10f0 net/mac80211/ibss.c:1708
2 locks held by getty/4030:
 #0: ffff88814cd77098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198
3 locks held by kworker/1:5/4310:
 #0: ffff888017471938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc900040a7d00 ((crda_timeout).work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: crda_timeout_work+0x11/0x50 net/wireless/reg.c:539
3 locks held by kworker/1:6/4314:
 #0: ffff888017471938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc900040d7d00 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffffffff8dd47f68 (rtnl_mutex
){+.+.}-{3:3}
, at: reg_check_chans_work+0x8e/0xda0 net/wireless/reg.c:2499
2 locks held by kworker/u4:5/4319:
5 locks held by kworker/u4:6/4324:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004127d00 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffff88801f3a87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5693 [inline]
 #2: ffff88801f3a87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x260 net/wireless/core.c:420
 #3: ffff888079a40d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1114 [inline]
 #3: ffff888079a40d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa8/0x10f0 net/mac80211/ibss.c:1680
 #4: ffff88801f3a9760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_sta_expire net/mac80211/ibss.c:1256 [inline]
 #4: ffff88801f3a9760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_sta_merge_ibss net/mac80211/ibss.c:1299 [inline]
 #4: ffff88801f3a9760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x57f/0x10f0 net/mac80211/ibss.c:1708
5 locks held by kworker/u4:7/4335:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004187d00 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffff8880549b87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5693 [inline]
 #2: ffff8880549b87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x260 net/wireless/core.c:420
 #3: 
ffff88801a2bcd40
 (&wdev->mtx){+.+.}-{3:3}
, at: sdata_lock net/mac80211/ieee80211_i.h:1114 [inline]
, at: ieee80211_ibss_work+0xa8/0x10f0 net/mac80211/ibss.c:1680
 #4: 
ffff8880549b9760
 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_sta_expire net/mac80211/ibss.c:1256 [inline]
 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_sta_merge_ibss net/mac80211/ibss.c:1299 [inline]
 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x57f/0x10f0 net/mac80211/ibss.c:1708
4 locks held by udevd/4345:
 #0: ffff88802fc26418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
 #1: ffff8880593a1c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x58/0x410 fs/kernfs/file.c:172
 #2: ffff88807d08bcb8 (kn->active#30){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
 #2: ffff88807d08bcb8 (kn->active#30){.+.+}-{0:0}, at: kernfs_seq_start+0xae/0x410 fs/kernfs/file.c:173
 #3: ffff88801e65e190 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:845 [inline]
 #3: ffff88801e65e190 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x22/0x90 drivers/usb/core/sysfs.c:141
6 locks held by kworker/0:7/4347:
5 locks held by kworker/u4:8/4374:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004297d00 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #2: ffff8880768e87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: wiphy_lock include/net/cfg80211.h:5693 [inline]
 #2: ffff8880768e87a8 (&rdev->wiphy.mtx){+.+.}-{3:3}, at: cfg80211_wiphy_work+0x31/0x260 net/wireless/core.c:420
 #3: ffff8880557a8d40 (&wdev->mtx){+.+.}-{3:3}, at: sdata_lock net/mac80211/ieee80211_i.h:1114 [inline]
 #3: ffff8880557a8d40 (&wdev->mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0xa8/0x10f0 net/mac80211/ibss.c:1680
 #4: ffff8880768e9760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_sta_expire net/mac80211/ibss.c:1256 [inline]
 #4: ffff8880768e9760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_sta_merge_ibss net/mac80211/ibss.c:1299 [inline]
 #4: ffff8880768e9760 (&local->sta_mtx){+.+.}-{3:3}, at: ieee80211_ibss_work+0x57f/0x10f0 net/mac80211/ibss.c:1708
2 locks held by kworker/u4:9/4592:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004e0fd00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
2 locks held by kworker/u4:10/4627:
 #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
 #1: ffffc90004a77d00
 (
connector_reaper_work
){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267
2 locks held by syz.2.139/4838:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492
 #1: 
ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962
2 locks held by syz.2.139/4840:
 #0: 
ffffffff8dd3b090
 (
pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x32e/0x5b0 net/core/net_namespace.c:504
 #1: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: register_nexthop_notifier+0x84/0x240 net/ipv4/nexthop.c:3619
2 locks held by syz.2.139/4841:
 #0: ffffffff8dda8350 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
 #1: ffffffff8dd47f68 (rtnl_mutex
){+.+.}-{3:3}
, at: nl80211_pre_doit+0x5b/0x930 net/wireless/nl80211.c:16369
1 lock held by syz.1.140/4843:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x3fc/0x1e60 drivers/net/tun.c:3104
1 lock held by syz.1.140/4854:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz.4.141/4844:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3492
2 locks held by syz.4.141/4853:
 #0: ffffffff8dda8350 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:860
 #1: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}
, at: nl80211_pre_doit+0x5b/0x930 net/wireless/nl80211.c:16369
2 locks held by syz.0.143/4857:
 #0: ffff888068468810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline]
 #0: ffff888068468810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline]
 #0: ffff888068468810 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1399
 #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962
1 lock held by syz.0.143/4858:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz.3.145/4866:
 #0: ffffffff8c9ebb28 (sched_core_mutex){+.+.}-{3:3}, at: sched_core_get+0x49/0x1c0 kernel/sched/core.c:399
1 lock held by syz.3.145/4870:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4877:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4879:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4881:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4883:
 #0: ffffffff8dd47f68
 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4886:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by dhcpcd/4888:
 #0: ffff8880547c8130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff8880547c8130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/4889:
 #0: ffff8881417a4130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff8881417a4130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/4890:
 #0: ffff8881417a2130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff8881417a2130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/4891:
 #0: ffff888053cfa130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff888053cfa130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/4892:
 #0: ffff888053cfe130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff888053cfe130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by dhcpcd/4893:
 #0: ffff88801fb76130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline]
 #0: ffff88801fb76130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249
1 lock held by syz-executor/4898:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4900:
 #0: 
ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4902:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4903:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4907:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4913:
 #0: 
ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4915:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4917:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4918:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154
1 lock held by syz-executor/4922:
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8dd47f68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x824/0xfc0 net/core/rtnetlink.c:6154

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 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+0xeee/0xf30 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4347 Comm: kworker/0:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_out+0x78/0xb0 drivers/tty/serial/8250/8250_port.c:468
Code: d0 ff 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 a0 dc 50 fd 41 03 2e 89 d8 89 ea ee <5b> 41 5c 41 5e 41 5f 5d c3 44 89 f9 80 e1 07 38 c1 7c aa 4c 89 ff
RSP: 0018:ffffc90003de5f90 EFLAGS: 00000002
RAX: 0000000000000020 RBX: 0000000000000020 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 00000000000fffff RDI: 0000000000100000
RBP: 00000000000003f8 R08: ffff888024620237 R09: 1ffff110048c4046
R10: dffffc0000000000 R11: ffffed10048c4047 R12: dffffc0000000000
R13: ffffffff96c42e03 R14: ffffffff96f87520 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b733b50000 CR3: 000000007e73f000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 serial_out drivers/tty/serial/8250/8250.h:122 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
 serial8250_console_write+0x114b/0x17f0 drivers/tty/serial/8250/8250_port.c:3479
 call_console_driver kernel/printk/printk.c:1977 [inline]
 console_emit_next_record+0x79e/0xba0 kernel/printk/printk.c:2777
 console_flush_all kernel/printk/printk.c:-1 [inline]
 console_unlock+0x223/0x630 kernel/printk/printk.c:2906
 vprintk_emit+0x4b3/0x6a0 kernel/printk/printk.c:2303
 dev_vprintk_emit+0x34e/0x400 drivers/base/core.c:4933
 dev_printk_emit+0xeb/0x139 drivers/base/core.c:4944
 _dev_err+0x11b/0x16c drivers/base/core.c:4999
 parse_uac2_sample_rate_range+0x992/0xc60 sound/usb/format.c:401
 parse_audio_format_rates_v2v3+0x3c7/0x16c0 sound/usb/format.c:636
 parse_audio_format_ii sound/usb/format.c:778 [inline]
 snd_usb_parse_audio_format+0x4ae/0x740 sound/usb/format.c:799
 snd_usb_get_audioformat_uac12 sound/usb/stream.c:854 [inline]
 __snd_usb_parse_audio_interface+0x18b1/0x4b00 sound/usb/stream.c:1196
 snd_usb_parse_audio_interface+0x36/0xb0 sound/usb/stream.c:1274
 create_standard_audio_quirk+0x59/0x120 sound/usb/quirks.c:100
 snd_usb_create_quirk sound/usb/quirks.c:539 [inline]
 create_composite_quirk+0x1ec/0x4e0 sound/usb/quirks.c:48
 usb_audio_probe+0xb97/0x1d90 sound/usb/card.c:885
 usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2223
 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_new_device+0xd66/0x1650 drivers/usb/core/hub.c:2659
 hub_port_connect drivers/usb/core/hub.c:5517 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5657 [inline]
 port_event drivers/usb/core/hub.c:5817 [inline]
 hub_event+0x2dcf/0x5560 drivers/usb/core/hub.c:5899
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/27 20:17 linux-6.1.y 7c87defbd336 0f700595 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in __lru_add_drain_all
2026/04/26 23:22 linux-6.1.y 7c87defbd336 9c2d0995 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in __lru_add_drain_all
2026/04/13 09:20 linux-6.1.y 8e8fc038cad5 38c8e246 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in __lru_add_drain_all
2026/03/10 22:54 linux-6.1.y f2ddafa93a25 4683d576 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan INFO: task hung in __lru_add_drain_all
* Struck through repros no longer work on HEAD.