INFO: task syz-executor.2:20070 blocked for more than 143 seconds. Not tainted 6.10.0-rc3-syzkaller-00022-gcea2a26553ac #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:27840 pid:20070 tgid:20068 ppid:19010 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 nfsd_nl_threads_get_doit+0x1c6/0x7d0 fs/nfsd/nfsctl.c:1757 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x16b/0x440 net/netlink/af_netlink.c:2564 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline] netlink_unicast+0x542/0x820 net/netlink/af_netlink.c:1361 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0xab5/0xc90 net/socket.c:2585 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2639 __sys_sendmsg+0x117/0x1f0 net/socket.c:2668 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8368c7cea9 RSP: 002b:00007f8369a710c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8368db3f80 RCX: 00007f8368c7cea9 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007f8368cebff4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f8368db3f80 R15: 00007ffc121dd2e8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8dbb1920 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #0: ffffffff8dbb1920 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #0: ffffffff8dbb1920 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by getty/4834: #0: ffff88802a5540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 1 lock held by syz-fuzzer/5075: 3 locks held by kworker/0:4/10299: #0: ffff888015480948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12bf/0x1b60 kernel/workqueue.c:3206 #1: ffffc900032cfd80 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x957/0x1b60 kernel/workqueue.c:3207 #2: ffffffff8dbbd0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:291 2 locks held by syz-executor.0/19218: #0: ffffffff8f7e9d90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8dfb2f48 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_listener_set_doit+0xe3/0x1b30 fs/nfsd/nfsctl.c:1966 1 lock held by syz-executor.1/19451: 3 locks held by kworker/u8:0/20032: 2 locks held by syz-executor.2/20070: #0: ffffffff8f7e9d90 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8dfb2f48 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_threads_get_doit+0x1c6/0x7d0 fs/nfsd/nfsctl.c:1757 3 locks held by syz-executor.4/20215: #0: ffff8880560b0d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:554 #1: ffff8880560b0078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x339/0x1100 net/bluetooth/hci_sync.c:5050 #2: ffffffff8f9adba8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1982 [inline] #2: ffffffff8f9adba8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xc4/0x260 net/bluetooth/hci_conn.c:2584 2 locks held by syz-executor.2/20315: 3 locks held by syz-executor.3/20448: #0: ffff888063cf4d88 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:554 #1: ffff888063cf4078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_close_sync+0x339/0x1100 net/bluetooth/hci_sync.c:5050 #2: ffffffff8f9adba8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:1982 [inline] #2: ffffffff8f9adba8 (hci_cb_list_lock){+.+.}-{3:3}, at: hci_conn_hash_flush+0xc4/0x260 net/bluetooth/hci_conn.c:2584 1 lock held by syz-executor.0/21407: #0: ffffffff8dbbd0b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:323 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 30 Comm: khungtaskd Not tainted 6.10.0-rc3-syzkaller-00022-gcea2a26553ac #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline] watchdog+0xf86/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112