INFO: task syz.0.609:8340 blocked for more than 154 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.609 state:D stack:27512 pid:8340 tgid:8339 ppid:5805 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xfe6/0x5fa0 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7021 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0xc9a/0x1b90 kernel/locking/mutex.c:776 bdev_open+0x41a/0xe40 block/bdev.c:962 blkdev_open+0x34e/0x4f0 block/fops.c:698 do_dentry_open+0x73e/0x1570 fs/open.c:962 vfs_open+0x82/0x3f0 fs/open.c:1094 do_open fs/namei.c:4637 [inline] path_openat+0x21dc/0x3120 fs/namei.c:4796 do_filp_open+0x1f7/0x420 fs/namei.c:4823 do_sys_openat2+0x12e/0x220 fs/open.c:1430 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x12d/0x210 fs/open.c:1447 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe71e35b78e RSP: 002b:00007fe71f2b4b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe71f2b56c0 RCX: 00007fe71e35b78e RDX: 0000000000040000 RSI: 00007fe71f2b4c00 RDI: ffffffffffffff9c RBP: 00007fe71f2b4c00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd R13: 00007fe71e616038 R14: 00007fe71e615fa0 R15: 00007ffc15de74c8 Showing all locks held in the system: 1 lock held by rcu_preempt/16: #0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline] #0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632 1 lock held by khungtaskd/31: #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff8e5e32e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 4 locks held by kworker/u8:2/36: #0: ffff88801c2dc948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90000ac7c98 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903dad70 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xab/0x830 net/core/net_namespace.c:670 #3: ffffffff903f36a8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0x90/0xc60 net/core/dev.c:13037 3 locks held by kworker/u8:4/60: #0: ffff88813fe69948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc9000211fc98 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff903f36a8 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:313 1 lock held by dhcpcd/5473: #0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:647 [inline] #0: ffff8880b843ac98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:632 2 locks held by getty/5569: #0: ffff888037a180a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by udevd/5820: #0: ffff888141f2f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:962 3 locks held by kworker/0:3/5856: #0: ffff88813fe51948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc900054efc98 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by syz.0.609/8340: #0: ffff888141f2f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:962 5 locks held by syz-executor/8722: #0: ffff88805ad9cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:499 #1: ffff88805ad9c0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5315 #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x280 net/bluetooth/hci_conn.c:2637 #3: ffff8880576b7338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x80/0x760 net/bluetooth/l2cap_core.c:1763 #4: ffffffff8e5efab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 3 locks held by syz-executor/8730: #0: ffff88805d30cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:499 #1: ffff88805d30c0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5315 #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x280 net/bluetooth/hci_conn.c:2637 3 locks held by syz.7.1091/10467: #0: ffff88805a0ecec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:499 #1: ffff88805a0ec0c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5315 #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x280 net/bluetooth/hci_conn.c:2637 3 locks held by syz.0.1095/10472: #0: ffff88807d3f8ec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0xb0 net/bluetooth/hci_core.c:499 #1: ffff88807d3f80c0 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x35c/0x1240 net/bluetooth/hci_sync.c:5315 #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2143 [inline] #2: ffffffff9068c768 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x280 net/bluetooth/hci_conn.c:2637 ============================================= 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 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x754/0xaf0 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 5473 Comm: dhcpcd Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417 Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e9 2b a7 fb f5 cc RSP: 0018:ffffc900033973f0 EFLAGS: 00000002 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff81e1ac97 RDI: ffffed10170a48c1 RBP: ffff8880b8524608 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000155cc0 R11: 00000000000001bc R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fb33df06740(0000) GS:ffff8881246d9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3a16147e20 CR3: 0000000079536000 CR4: 00000000003526f0 Call Trace: kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire kernel/locking/lockdep.c:5842 [inline] lock_acquire+0xf5/0x330 kernel/locking/lockdep.c:5825 do_write_seqcount_begin_nested include/linux/seqlock.h:477 [inline] do_write_seqcount_begin include/linux/seqlock.h:503 [inline] psi_write_begin kernel/sched/psi.c:183 [inline] psi_task_change+0x167/0x550 kernel/sched/psi.c:919 psi_enqueue kernel/sched/stats.h:166 [inline] enqueue_task+0x23b/0x560 kernel/sched/core.c:2096 activate_task kernel/sched/core.c:2135 [inline] ttwu_do_activate+0x17d/0xa90 kernel/sched/core.c:3631 ttwu_queue kernel/sched/core.c:3894 [inline] try_to_wake_up+0xc47/0x1a60 kernel/sched/core.c:4218 autoremove_wake_function+0x16/0x150 kernel/sched/wait.c:403 __wake_up_common+0x135/0x1f0 kernel/sched/wait.c:108 __wake_up_common_lock kernel/sched/wait.c:125 [inline] __wake_up+0x31/0x60 kernel/sched/wait.c:146 audit_log_end.part.0+0x1ca/0x280 kernel/audit.c:2645 audit_log_end+0x1f/0x30 kernel/audit.c:2638 common_lsm_audit+0x24c/0x2b0 security/lsm_audit.c:456 slow_avc_audit+0x186/0x210 security/selinux/avc.c:779 avc_audit security/selinux/include/avc.h:131 [inline] avc_has_perm+0x1a6/0x1e0 security/selinux/avc.c:1198 sock_has_perm+0x251/0x2f0 security/selinux/hooks.c:4815 security_socket_recvmsg+0xa5/0x260 security/security.c:4227 sock_recvmsg+0x4a/0x250 net/socket.c:1098 ____sys_recvmsg+0x218/0x6b0 net/socket.c:2812 ___sys_recvmsg+0x16a/0x1a0 net/socket.c:2854 __sys_recvmsg+0x16d/0x220 net/socket.c:2887 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb33df90407 Code: 48 89 fa 4c 89 df e8 38 aa 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:00007ffed68a4f70 EFLAGS: 00000202 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 00007fb33df06740 RCX: 00007fb33df90407 RDX: 0000000000000000 RSI: 00007ffed68a5000 RDI: 0000000000000010 RBP: 00007ffed68a7440 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000556476123870 R13: 00007ffed68a50c0 R14: 00007ffed68a500c R15: 00007ffed68a71f0