INFO: task kworker/u9:1:5139 blocked for more than 143 seconds. Not tainted 6.15.0-rc7-syzkaller-01658-gea15e046263b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u9:1 state:D stack:27192 pid:5139 tgid:5139 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: hci1 hci_rx_work Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 hci_event_func net/bluetooth/hci_event.c:7511 [inline] hci_event_packet+0x7e3/0x1200 net/bluetooth/hci_event.c:7565 hci_rx_work+0x46a/0xe80 net/bluetooth/hci_core.c:4036 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz-executor:5929 blocked for more than 144 seconds. Not tainted 6.15.0-rc7-syzkaller-01658-gea15e046263b #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor state:D stack:22136 pid:5929 tgid:5929 ppid:1 task_flags:0x40054c flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 __flush_work+0x9b9/0xbc0 kernel/workqueue.c:4244 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4364 hidp_session_remove+0x62/0x260 net/bluetooth/hidp/core.c:1169 l2cap_unregister_all_users net/bluetooth/l2cap_core.c:1748 [inline] l2cap_conn_del+0x23d/0x680 net/bluetooth/l2cap_core.c:1777 hci_disconn_cfm include/net/bluetooth/hci_core.h:2065 [inline] hci_conn_hash_flush+0x10a/0x230 net/bluetooth/hci_conn.c:2543 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5225 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline] hci_unregister_dev+0x206/0x500 net/bluetooth/hci_core.c:2678 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:665 __fput+0x44c/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x8d6/0x2550 kernel/exit.c:953 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x125e/0x1310 kernel/signal.c:3034 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe5caf8df17 RSP: 002b:00007ffe3a22b918 EFLAGS: 00000206 ORIG_RAX: 0000000000000057 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fe5caf8df17 RDX: 00007ffe3a22b940 RSI: 00007ffe3a22b9d0 RDI: 00007ffe3a22b9d0 RBP: 00007ffe3a22b9d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe3a22ca60 R13: 00007fe5cb01089d R14: 000000000001f705 R15: 00007ffe3a22caa0 INFO: task khidpd_16c05505:5971 blocked for more than 145 seconds. Not tainted 6.15.0-rc7-syzkaller-01658-gea15e046263b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khidpd_16c05505 state:D stack:29576 pid:5971 tgid:5971 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1728 hidp_session_thread+0x3c9/0x410 net/bluetooth/hidp/core.c:1304 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.0.616:6591 blocked for more than 146 seconds. Not tainted 6.15.0-rc7-syzkaller-01658-gea15e046263b #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.616 state:D stack:27288 pid:6591 tgid:6591 ppid:6578 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 l2cap_sock_connect+0x5c5/0x7a0 net/bluetooth/l2cap_sock.c:256 __sys_connect_file net/socket.c:2038 [inline] __sys_connect+0x316/0x440 net/socket.c:2057 __do_sys_connect net/socket.c:2063 [inline] __se_sys_connect net/socket.c:2060 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2060 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff97d58e969 RSP: 002b:00007fffe499daf8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007ff97d7b5fa0 RCX: 00007ff97d58e969 RDX: 000000000000000e RSI: 0000200000000080 RDI: 0000000000000005 RBP: 00007ff97d610ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff97d7b5fa0 R14: 00007ff97d7b5fa0 R15: 0000000000000003 Showing all locks held in the system: 8 locks held by kworker/1:0/24: 1 lock held by khungtaskd/31: #0: ffffffff8df3dee0 ( rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:841 [inline] , at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 4 locks held by kworker/u9:0/56: #0: ffff88807e6f9148 ((wq_completion)hci4#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88807e6f9148 ((wq_completion)hci4#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000101fc60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000101fc60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff888030a34078 (&hdev->lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 ( hci_cb_list_lock ){+.+.}-{4:4} , at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] , at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 4 locks held by kworker/u9:1/5139: #0: ffff888027c2c148 ( (wq_completion)hci1 #2 ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000ee47c60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000ee47c60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880632ec078 (&hdev->lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 ( hci_cb_list_lock ){+.+.}-{4:4} , at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] , at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 2 locks held by getty/5593: #0: ffff8880308820a0 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 ( &ldata->atomic_read_lock ){+.+.}-{4:4} , at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/u9:2/5883: #0: ffff88807ce99148 ((wq_completion)hci5#2){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000484fc60 ((work_completion)(&hdev->rx_work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3214 [inline] , at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880719bc078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 ( hci_cb_list_lock ){+.+.}-{4:4} , at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] , at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 5 locks held by syz-executor/5929: #0: ffff88802596cd80 ( &hdev->req_lock ){+.+.}-{4:4} , at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline] , at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678 #1: ffff88802596c078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213 #2: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2062 [inline] (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2543 #3: ffff88807faa1b38 (&conn->lock#2){+.+.}-{4:4} , at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762 #4: ffffffff8f48b4f0 ( hidp_session_sem ){++++}-{4:4} , at: hidp_session_remove+0x2c/0x260 net/bluetooth/hidp/core.c:1165 1 lock held by khidpd_16c05505/5971: #0: ffff88802596c078 ( &hdev->lock ){+.+.}-{4:4} , at: l2cap_unregister_user+0x6a/0x1b0 net/bluetooth/l2cap_core.c:1728 1 lock held by syz.0.616/6591: #0: ffff8880632ec078 (&hdev->lock ){+.+.}-{4:4} , at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 4 locks held by kworker/u9:3/6596: #0: ffff888064acb148 ((wq_completion)hci2 #2 ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000d327c60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880640a0078 (&hdev->lock){+.+.}-{4:4} , at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 ( hci_cb_list_lock ){+.+.}-{4:4} , at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] , at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 1 lock held by syz.1.617/6608: #0: ffff8880640a0078 ( &hdev->lock ){+.+.}-{4:4} , at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 4 locks held by kworker/u9:4/6612: #0: ffff888028a30948 ( (wq_completion)hci3 #2 ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000d3afc60 ( (work_completion)(&hdev->rx_work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3214 [inline] , at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880713dc078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] (hci_cb_list_lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 1 lock held by syz.2.618/6625: #0: ffff8880713dc078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 4 locks held by kworker/u9:5/6629: #0: ffff88805fc54148 ((wq_completion)hci9#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88805fc54148 ((wq_completion)hci9#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000396fc60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000396fc60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff88807d1c0078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] (hci_cb_list_lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 1 lock held by syz.3.619/6642: #0: ffff888030a34078 ( &hdev->lock ){+.+.}-{4:4} , at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 4 locks held by kworker/u9:6/6651: #0: ffff888029098948 ((wq_completion)hci6#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] ((wq_completion)hci6#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000d4d7c60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000d4d7c60 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880715c4078 (&hdev->lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] #3: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 1 lock held by syz.4.620/6669: #0: ffff8880719bc078 ( &hdev->lock ){+.+.}-{4:4} , at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 4 locks held by kworker/u9:7/6673: #0: ffff8880222c1948 ( (wq_completion)hci8 #2 ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000d567c60 ( (work_completion)(&hdev->rx_work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3214 [inline] , at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff888064b1c078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 ( hci_cb_list_lock ){+.+.}-{4:4} , at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] , at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 1 lock held by syz.5.621/6691: #0: ffff8880715c4078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 4 locks held by kworker/u9:8/6696: #0: ffff88806ecdd948 ( (wq_completion)hci7 #2 ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3213 [inline] , at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000d5dfc60 ( (work_completion)(&hdev->rx_work) ){+.+.}-{0:0} , at: process_one_work kernel/workqueue.c:3214 [inline] , at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff8880328fc078 ( &hdev->lock ){+.+.}-{4:4} , at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713 #3: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline] #3: ffffffff8f462668 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747 1 lock held by syz.6.622/6713: #0: ffff8880328fc078 (&hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 1 lock held by syz.7.623/6741: #0: ffff888064b1c078 ( &hdev->lock){+.+.}-{4:4}, at: l2cap_chan_connect+0x102/0xe30 net/bluetooth/l2cap_core.c:6956 3 locks held by syz-executor/6743: #0: ffffffff8ea945e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ea945e0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ea945e0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8f2fab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8f2fab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8f2fab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4065 #2: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #2: ffffffff8df439b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc7-syzkaller-01658-gea15e046263b #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113