INFO: task syz.0.517:8216 blocked for more than 142 seconds. Not tainted 6.14.0-syzkaller-13408-g9f867ba24d36 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.517 state:D stack:26984 pid:8216 tgid:8208 ppid:5836 task_flags:0x400140 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 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+0x6c7/0xb90 kernel/locking/mutex.c:746 nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1771 genl_family_rcv_msg_doit+0x206/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x55c/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x16a/0x440 net/netlink/af_netlink.c:2534 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] ____sys_sendmsg+0xa95/0xc70 net/socket.c:2566 ___sys_sendmsg+0x134/0x1d0 net/socket.c:2620 __sys_sendmsg+0x16d/0x220 net/socket.c:2652 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f679ab8d169 RSP: 002b:00007f679ba3c038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f679ada6080 RCX: 00007f679ab8d169 RDX: 0000000000000844 RSI: 00002000000004c0 RDI: 0000000000000004 RBP: 00007f679ac0e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f679ada6080 R15: 00007ffdd48ed5f8 Showing all locks held in the system: 4 locks held by rcu_exp_gp_kthr/18: #0: ffff8880b8539f18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 #1: ffff8880b8523c48 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987 #2: ffff888063d6a828 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:557 [inline] #2: ffff888063d6a828 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xb2/0x1680 kernel/sched/core.c:4212 #3: ffff8880b8539f18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 1 lock held by khungtaskd/31: #0: ffffffff8e3c1580 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3c1580 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3c1580 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 3 locks held by kworker/1:1/48: #0: ffff88801b480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90000b97d18 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff8e3ccab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336 1 lock held by kworker/1:2/2156: #0: ffff8880b8539f18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 2 locks held by syz.2.413/7746: #0: ffffffff901cfa10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e7cd1e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x698/0xbf0 fs/nfsd/nfsctl.c:1629 2 locks held by syz-executor/7977: #0: ffff88803345a0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88803345a0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88803345a0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline] #0: ffff88803345a0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:502 #1: ffffffff8e7cd1e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 2 locks held by syz.0.517/8216: #0: ffffffff901cfa10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e7cd1e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_version_set_doit+0xc4/0x7a0 fs/nfsd/nfsctl.c:1771 2 locks held by syz.5.596/8552: #0: ffffffff901cfa10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8e7cd1e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x698/0xbf0 fs/nfsd/nfsctl.c:1629 2 locks held by getty/8613: #0: ffff8880369a20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000f9432f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/8644: #0: ffff8880353020e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff8880353020e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff8880353020e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline] #0: ffff8880353020e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:502 #1: ffffffff8e7cd1e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 2 locks held by syz-executor/9109: #0: ffff88808741c0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88808741c0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88808741c0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline] #0: ffff88808741c0e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super+0xd6/0x100 fs/super.c:502 #1: ffffffff8e7cd1e8 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x5b/0xf0 fs/nfsd/nfssvc.c:596 2 locks held by kworker/u8:35/9587: #0: ffff88801c746948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90004a1fd18 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 3 locks held by kworker/u8:36/9588: #0: ffff8880b8539f18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 #1: ffff8880b8523c48 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987 #2: ffff8880b85256d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x127/0x1d0 kernel/time/timer.c:1046 4 locks held by kworker/u8:37/9589: #0: ffff88801c2f6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900049e7d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90117b10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xc9/0xb30 net/core/net_namespace.c:608 #3: ffffffff8e3cc980 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3774 3 locks held by syz-executor/10042: #0: ffff8880299a0d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:481 #1: ffff8880299a0078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x3ae/0x11d0 net/bluetooth/hci_sync.c:5213 #2: ffffffff8e3ccab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336 3 locks held by syz.9.942/10285: 4 locks held by syz.2.941/10303: #0: ffff888040cf0d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:481 #1: ffff888040cf0078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x3ae/0x11d0 net/bluetooth/hci_sync.c:5213 #2: ffffffff9039c7c8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2066 [inline] #2: ffffffff9039c7c8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x260 net/bluetooth/hci_conn.c:2701 #3: ffff88808933d338 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x80/0x730 net/bluetooth/l2cap_core.c:1761 2 locks held by rm/10324: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-syzkaller-13408-g9f867ba24d36 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9588 Comm: kworker/u8:36 Not tainted 6.14.0-syzkaller-13408-g9f867ba24d36 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_wait_context kernel/locking/lockdep.c:4871 [inline] RIP: 0010:__lock_acquire+0x254/0x1ba0 kernel/locking/lockdep.c:5185 Code: 0f 88 58 0d 00 00 49 63 c5 48 8d 04 80 48 8d 44 c5 00 eb 12 41 83 ed 01 48 83 e8 28 41 83 fd ff 0f 84 64 05 00 00 0f b6 50 21 <31> ca 83 e2 60 74 e3 41 83 c5 01 65 8b 05 a2 ad 0e 12 85 c0 0f 84 RSP: 0018:ffffc90004a0f960 EFLAGS: 00000002 RAX: ffff888030e8c718 RBX: ffff888030e8c740 RCX: 0000000000000007 RDX: 0000000000000007 RSI: 0000000000000003 RDI: 0000000000000002 RBP: ffff888030e8c6f0 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: ffff888062afc318 R12: 0000000000000000 R13: 0000000000000001 R14: ffff888030e8bc00 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881249b9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000557edb6a8950 CR3: 000000008b208000 CR4: 00000000003526f0 Call Trace: lock_acquire kernel/locking/lockdep.c:5866 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5823 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xd9/0x3a0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x958/0x1030 net/batman-adv/network-coding.c:722 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245