INFO: task syz.2.4259:24219 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.4259 state:D stack:28296 pid:24219 tgid:24218 ppid:18427 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7083 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:980 [inline] blkdev_fallocate+0x260/0x530 block/fops.c:911 vfs_fallocate+0x669/0x7e0 fs/open.c:342 ksys_fallocate fs/open.c:366 [inline] __do_sys_fallocate fs/open.c:371 [inline] __se_sys_fallocate fs/open.c:369 [inline] __x64_sys_fallocate+0xc0/0x110 fs/open.c:369 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: 0033:0x7fc5eff8f749 RSP: 002b:00007fc5ee1ee038 EFLAGS: 00000246 ORIG_RAX: 000000000000011d RAX: ffffffffffffffda RBX: 00007fc5f01e5fa0 RCX: 00007fc5eff8f749 RDX: 0000000000000000 RSI: 0000000000000011 RDI: 0000000000000003 RBP: 00007fc5f0013f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000074000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc5f01e6038 R14: 00007fc5f01e5fa0 R15: 00007fc5f030fa28 Showing all locks held in the system: 2 locks held by init/1: 1 lock held by khungtaskd/31: #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8df3d6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 1 lock held by klogd/5188: 2 locks held by getty/5589: #0: ffff8880336320a0 (&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 4 locks held by kworker/u9:3/5829: #0: ffff888075db6948 ((wq_completion)hci7){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline] #0: ffff888075db6948 ((wq_completion)hci7){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346 #1: ffffc90003fefba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline] #1: ffffc90003fefba0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346 #2: ffff888053aa0dc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 #3: ffff888053aa00b8 (&hdev->lock){+.+.}-{4:4}, at: hci_abort_conn_sync+0x242/0xe30 net/bluetooth/hci_sync.c:5684 3 locks held by syz-executor/22862: 1 lock held by syz-executor/22869: #0: ffffffff8df43178 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #0: ffffffff8df43178 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 2 locks held by syz.1.4117/23671: #0: ffff888148dbb5a8 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #0: ffff888148dbb5a8 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x260/0x530 block/fops.c:911 #1: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock include/linux/fs.h:1035 [inline] #1: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: blkdev_fallocate+0x290/0x530 block/fops.c:912 1 lock held by syz.2.4259/24219: #0: ffff888148dbb5a8 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: inode_lock include/linux/fs.h:980 [inline] #0: ffff888148dbb5a8 (&sb->s_type->i_mutex_key#8){++++}-{4:4}, at: blkdev_fallocate+0x260/0x530 block/fops.c:911 1 lock held by syz.4.4336/24525: #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1045 [inline] #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x3a2/0xe70 mm/readahead.c:494 1 lock held by syz.3.4505/25170: #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1045 [inline] #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x3a2/0xe70 mm/readahead.c:494 1 lock held by syz.6.4520/25223: #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1045 [inline] #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x3a2/0xe70 mm/readahead.c:494 1 lock held by syz.6.4520/25224: #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1045 [inline] #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x3a2/0xe70 mm/readahead.c:494 1 lock held by syz.6.4520/25231: #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: filemap_invalidate_lock_shared include/linux/fs.h:1045 [inline] #0: ffff888148dbb748 (mapping.invalidate_lock){++++}-{4:4}, at: page_cache_ra_order+0x3a2/0xe70 mm/readahead.c:494 5 locks held by syz-executor/25352: #0: ffff888047598dc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:499 [inline] #0: ffff888047598dc8 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x212/0x510 net/bluetooth/hci_core.c:2715 #1: ffff8880475980b8 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5296 #2: ffffffff8f4362e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2119 [inline] #2: ffffffff8f4362e8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2614 #3: ffff8880821c6338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1763 #4: ffffffff8df43178 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline] #4: ffffffff8df43178 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:957 ============================================= NMI backtrace for cpu 0 CPU: 0 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] check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline] watchdog+0xf60/0xfa0 kernel/hung_task.c:495 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 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: 25352 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__bfs kernel/locking/lockdep.c:1815 [inline] RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1860 [inline] RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2796 [inline] RIP: 0010:check_prev_add kernel/locking/lockdep.c:3169 [inline] RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3284 [inline] RIP: 0010:validate_chain+0xfd7/0x2140 kernel/locking/lockdep.c:3908 Code: 25 ff 0f 00 00 39 05 f4 7f d8 11 73 06 89 05 ec 7f d8 11 49 8b 04 24 48 89 de 48 39 e8 0f 84 33 fe ff ff 4c 89 68 30 48 8b 00 <48> 39 e8 75 f4 48 89 de e9 1f fe ff ff 48 c7 c7 b0 df e0 8d 48 89 RSP: 0018:ffffc9000bb3ec98 EFLAGS: 00000002 RAX: ffffffff9609df18 RBX: 00000000000003dd RCX: 000000000000047d RDX: 0000000000000008 RSI: 00000000000003dd RDI: ffff88802ccc3c80 RBP: ffffffff93173b98 R08: ffffc9000bb3ec60 R09: 0000000000000020 R10: dffffc0000000000 R11: ffffffff819dc2f0 R12: ffffffff95f9b1b8 R13: ffffffff95fb98a8 R14: ffff88802ccc4878 R15: 000000000000047c FS: 0000000000000000(0000) GS:ffff888126239000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f21934bc949 CR3: 000000007d56c000 CR4: 00000000003526f0 DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083 DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5237 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5868 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline] do_write_seqcount_begin include/linux/seqlock.h:503 [inline] psi_write_begin+0xab/0x160 kernel/sched/psi.c:183 psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 psi_sched_switch kernel/sched/stats.h:220 [inline] __schedule+0x22e9/0x4cc0 kernel/sched/core.c:6923 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:7113 preempt_schedule+0xae/0xc0 kernel/sched/core.c:7137 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xfd/0x110 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock+0x190/0x1f0 kernel/sched/wait.c:127 sock_def_readable+0x1fb/0x550 net/core/sock.c:3551 __netlink_sendskb net/netlink/af_netlink.c:1265 [inline] netlink_broadcast_deliver net/netlink/af_netlink.c:1401 [inline] do_one_broadcast net/netlink/af_netlink.c:1490 [inline] netlink_broadcast_filtered+0xc2e/0x1000 net/netlink/af_netlink.c:1535 netlink_broadcast+0x37/0x50 net/netlink/af_netlink.c:1559 uevent_net_broadcast_untagged lib/kobject_uevent.c:331 [inline] kobject_uevent_net_broadcast+0x378/0x560 lib/kobject_uevent.c:410 kobject_uevent_env+0x55b/0x8c0 lib/kobject_uevent.c:608 device_del+0x73a/0x8e0 drivers/base/core.c:3896 device_unregister+0x20/0xc0 drivers/base/core.c:3919 hci_conn_cleanup net/bluetooth/hci_conn.c:173 [inline] hci_conn_del+0xc33/0x11b0 net/bluetooth/hci_conn.c:1222 hci_conn_hash_flush+0x191/0x230 net/bluetooth/hci_conn.c:2615 hci_dev_close_sync+0xaef/0x1330 net/bluetooth/hci_sync.c:5308 hci_dev_do_close net/bluetooth/hci_core.c:501 [inline] hci_unregister_dev+0x21a/0x510 net/bluetooth/hci_core.c:2715 vhci_release+0x152/0x1a0 drivers/bluetooth/hci_vhci.c:690 __fput+0x44c/0xa70 fs/file_table.c:468 task_work_run+0x1d4/0x260 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x6b5/0x2300 kernel/exit.c:966 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x72/0x130 kernel/entry/common.c:40 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline] do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3ebab85897 Code: Unable to access opcode bytes at 0x7f3ebab8586d. RSP: 002b:00007ffc5d9d7970 EFLAGS: 00000293 ORIG_RAX: 000000000000003d RAX: fffffffffffffe00 RBX: 0000000000006310 RCX: 00007f3ebab85897 RDX: 0000000040000000 RSI: 00007ffc5d9d79ac RDI: 00000000ffffffff RBP: 00007ffc5d9d79ac R08: 0000000000000000 R09: 00000000ffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008 R13: 0000000000000003 R14: 00007ffc5d9d7c98 R15: 0000000000000000