INFO: task syz.1.451:7293 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.451 state:D stack:26920 pid:7293 tgid:7292 ppid:5843 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_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153 __flush_work+0xa17/0xc50 kernel/workqueue.c:4359 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline] p9_conn_destroy net/9p/trans_fd.c:804 [inline] p9_fd_close+0x245/0x430 net/9p/trans_fd.c:840 p9_client_create+0x68d/0xc90 net/9p/client.c:937 v9fs_session_init+0x46/0xdf0 fs/9p/v9fs.c:442 v9fs_get_tree+0xbd/0xac0 fs/9p/vfs_super.c:97 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3764 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3840 do_mount fs/namespace.c:4173 [inline] __do_sys_mount fs/namespace.c:4372 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4349 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: 0033:0x7f6322b9c799 RSP: 002b:00007f6323a72028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f6322e15fa0 RCX: 00007f6322b9c799 RDX: 0000200000000480 RSI: 0000200000000080 RDI: 0000000000000000 RBP: 00007f6322c32c99 R08: 00002000000003c0 R09: 0000000000000000 R10: 0000000000000084 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6322e16038 R14: 00007f6322e15fa0 R15: 00007ffca5ac2dc8 INFO: task syz.2.502:7482 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.502 state:D stack:27480 pid:7482 tgid:7481 ppid:5845 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_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153 __flush_work+0xa17/0xc50 kernel/workqueue.c:4359 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline] p9_conn_destroy net/9p/trans_fd.c:804 [inline] p9_fd_close+0x245/0x430 net/9p/trans_fd.c:840 p9_client_create+0x68d/0xc90 net/9p/client.c:937 v9fs_session_init+0x46/0xdf0 fs/9p/v9fs.c:442 v9fs_get_tree+0xbd/0xac0 fs/9p/vfs_super.c:97 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3764 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3840 do_mount fs/namespace.c:4173 [inline] __do_sys_mount fs/namespace.c:4372 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4349 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: 0033:0x7f0319f9c799 RSP: 002b:00007f031ae52028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f031a215fa0 RCX: 00007f0319f9c799 RDX: 00002000000002c0 RSI: 0000200000000300 RDI: 0000000000000000 RBP: 00007f031a032c99 R08: 00002000000005c0 R09: 0000000000000000 R10: 0000000000200480 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f031a216038 R14: 00007f031a215fa0 R15: 00007ffd120dccd8 INFO: task syz.3.505:7490 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.505 state:D stack:26056 pid:7490 tgid:7489 ppid:5842 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_timeout+0xc3/0x2c0 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:100 [inline] __wait_for_common kernel/sched/completion.c:121 [inline] wait_for_common kernel/sched/completion.c:132 [inline] wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153 __flush_work+0xa17/0xc50 kernel/workqueue.c:4359 p9_mux_poll_stop net/9p/trans_fd.c:140 [inline] p9_conn_destroy net/9p/trans_fd.c:804 [inline] p9_fd_close+0x245/0x430 net/9p/trans_fd.c:840 p9_client_create+0x68d/0xc90 net/9p/client.c:937 v9fs_session_init+0x46/0xdf0 fs/9p/v9fs.c:442 v9fs_get_tree+0xbd/0xac0 fs/9p/vfs_super.c:97 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3764 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3840 do_mount fs/namespace.c:4173 [inline] __do_sys_mount fs/namespace.c:4372 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4349 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: 0033:0x7f2a3499c799 RSP: 002b:00007f2a3579e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f2a34c15fa0 RCX: 00007f2a3499c799 RDX: 0000200000000480 RSI: 0000200000000440 RDI: 0000000000000000 RBP: 00007f2a34a32c99 R08: 00002000000004c0 R09: 0000000000000000 R10: 0000000000004898 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2a34c16038 R14: 00007f2a34c15fa0 R15: 00007ffdeb5d5d28 Showing all locks held in the system: 3 locks held by kworker/u8:0/12: #0: ffff88803198e940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc90000117c40 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11e/0x14c0 net/ipv6/addrconf.c:4198 3 locks held by kworker/u8:1/13: #0: ffff88801b0ac140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc90000127c40 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 #2: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:313 1 lock held by khungtaskd/30: #0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75d6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/0:2/91: #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc9000258fc40 (p9_poll_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 4 locks held by kworker/u8:5/113: #0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 #3: ffffffff9a496010 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x83/0x580 lib/debugobjects.c:846 2 locks held by getty/5599: #0: ffff888036e470a0 (&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/0x13c0 drivers/tty/n_tty.c:2211 2 locks held by kworker/1:4/5925: #0: ffff88801b06b140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x894/0x1780 kernel/workqueue.c:3261 #1: ffffc90004f07c40 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1780 kernel/workqueue.c:3262 3 locks held by syz-executor/8066: #0: ffff88807b68cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff88807b68cea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff88807b68c0b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346 #2: ffffffff8fd61e00 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8fd61e00 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644 7 locks held by syz-executor/9567: #0: ffff888035c44410 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline] #0: ffff888035c44410 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x227/0xb90 fs/read_write.c:684 #1: ffff88807aa16c80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1de/0x540 fs/kernfs/file.c:343 #2: ffff88802a0bd788 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff88802a0bd788 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x231/0x540 fs/kernfs/file.c:344 #3: ffffffff8f448300 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd7/0x370 drivers/net/netdevsim/bus.c:234 #4: ffff888076f3d0e0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:941 [inline] #4: ffff888076f3d0e0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1106 [inline] #4: ffff888076f3d0e0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x860 drivers/base/dd.c:1304 #5: ffff888076f5a258 (&devlink->lock_key#3){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x170 drivers/net/netdevsim/dev.c:1778 #6: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x10b/0x730 drivers/net/netdevsim/netdev.c:1177 2 locks held by syz-executor/9654: #0: ffffffff8f335e68 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8f335e68 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8f335e68 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570 #1: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline] #1: ffffffff8fbd5a40 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8a1/0x1be0 net/core/rtnetlink.c:4071 5 locks held by syz.2.1009/9715: #0: ffff888046a74ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff888046a74ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff888046a740b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346 #2: ffffffff8fd61e00 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8fd61e00 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644 #3: ffff888054bb7af0 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x7b/0x5c0 net/bluetooth/l2cap_core.c:1751 #4: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #4: ffffffff8e7638e8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770 kernel/rcu/tree_exp.h:961 3 locks held by syz.1.1006/9720: #0: ffff8880463f0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:500 [inline] #0: ffff8880463f0ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x5a0 net/bluetooth/hci_core.c:2716 #1: ffff8880463f00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x640/0x10e0 net/bluetooth/hci_sync.c:5346 #2: ffffffff8fd61e00 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2151 [inline] #2: ffffffff8fd61e00 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x260 net/bluetooth/hci_conn.c:2644 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 113 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound cfg80211_wiphy_work RIP: 0010:__kasan_check_read+0xa/0x20 mm/kasan/shadow.c:31 Code: 31 ed eb cf cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 89 f6 48 8b 0c 24 <31> d2 e9 8f e5 ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc900027579e0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff81cebf8c RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90123cf0 RBP: dffffc0000000000 R08: ffff88804b0c5a7b R09: 1ffff11009618b4f R10: dffffc0000000000 R11: ffffed1009618b50 R12: ffff88804b0c5a60 R13: ffff88804b0c5a60 R14: ffff88804b0c5a78 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125537000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7888f53000 CR3: 000000000e54a000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:82 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:649 [inline] cpu_online include/linux/cpumask.h:1231 [inline] trace_irq_enable+0x2c/0x150 include/trace/events/preemptirq.h:40 trace_hardirqs_on+0x18/0x40 kernel/trace/trace_preemptirq.c:73 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] _raw_spin_unlock_irqrestore+0x30/0x80 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] skb_dequeue+0x124/0x160 net/core/skbuff.c:3961 ieee80211_iface_work+0xbe8/0x1380 net/mac80211/iface.c:1799 cfg80211_wiphy_work+0x2ab/0x4a0 net/wireless/core.c:439 process_one_work+0x9ab/0x1780 kernel/workqueue.c:3289 process_scheduled_works kernel/workqueue.c:3380 [inline] worker_thread+0xba8/0x11e0 kernel/workqueue.c:3466 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