INFO: task syz.4.7055:21390 blocked for more than 143 seconds. Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.7055 state:D stack:25496 pid:21390 tgid:21389 ppid:5237 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5322 [inline] __schedule+0x1895/0x4b30 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6774 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752 nfsd_nl_threads_get_doit+0x1c5/0x7b0 fs/nfsd/nfsctl.c:1755 genl_family_rcv_msg_doit net/netlink/genetlink.c:1115 [inline] genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0xb16/0xec0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x1e5/0x430 net/netlink/af_netlink.c:2551 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline] netlink_unicast+0x7f8/0x990 net/netlink/af_netlink.c:1357 netlink_sendmsg+0x8e4/0xcb0 net/netlink/af_netlink.c:1901 sock_sendmsg_nosec net/socket.c:729 [inline] __sock_sendmsg+0x223/0x270 net/socket.c:744 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2607 ___sys_sendmsg net/socket.c:2661 [inline] __sys_sendmsg+0x292/0x380 net/socket.c:2690 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe97bb7dff9 RSP: 002b:00007fe97b5ff038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fe97bd35f80 RCX: 00007fe97bb7dff9 RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003 RBP: 00007fe97bbf0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe97bd35f80 R15: 00007ffddef086a8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720 2 locks held by kworker/u8:3/52: 2 locks held by getty/4975: #0: ffff88802e4f90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by syz-executor/5240: 5 locks held by kworker/0:3/5294: 2 locks held by kworker/0:8/5370: 1 lock held by udevd/5401: #0: ffff8880b863ea98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:593 2 locks held by syz.2.6221/19575: #0: ffffffff8fd38970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8ec19008 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964 2 locks held by syz.4.7055/21390: #0: ffffffff8fd38970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8ec19008 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_threads_get_doit+0x1c5/0x7b0 fs/nfsd/nfsctl.c:1755 3 locks held by syz.4.8218/23953: #0: ffffffff8fd38970 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffff88805ef116c8 (nlk_cb_mutex-GENERIC){+.+.}-{3:3}, at: __netlink_dump_start+0x119/0x790 net/netlink/af_netlink.c:2405 #2: ffffffff8ec19008 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_rpc_status_get_dumpit+0xdc/0x1a60 fs/nfsd/nfsctl.c:1558 2 locks held by kworker/u8:10/25116: 1 lock held by syz.4.9154/26039: #0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #0: ffffffff8e93d378 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:976 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 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+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/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 CPU: 1 UID: 0 PID: 25116 Comm: kworker/u8:10 Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:__local_bh_disable_ip+0xe4/0x220 kernel/softirq.c:321 Code: 60 42 80 3c 23 00 74 08 4c 89 f7 e8 a6 0f a7 00 48 8d 7c 24 40 4c 8b 74 24 60 fa 65 44 01 3d cb 4c ac 7e 65 8b 05 c4 4c ac 7e <44> 31 f8 a9 00 ff 00 00 75 10 48 89 fb 48 8b 7c 24 18 e8 15 9c 18 RSP: 0018:ffffc9000e9ff9c0 EFLAGS: 00000082 RAX: 0000000080000201 RBX: 1ffff92001d3ff44 RCX: 0000000000000034 RDX: 1ffff11005d891b1 RSI: 0000000000000201 RDI: ffffc9000e9ffa00 RBP: ffffc9000e9ffa98 R08: ffffffff942c98df R09: 1ffffffff285931b R10: dffffc0000000000 R11: fffffbfff285931c R12: dffffc0000000000 R13: 1ffff92001d3ff3c R14: 0000000000000246 R15: 0000000000000201 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3afb33 CR3: 0000000079a76000 CR4: 0000000000350ef0 Call Trace: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:125 [inline] _raw_spin_lock_bh+0x1c/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xe8/0x3b0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x365/0x610 net/batman-adv/network-coding.c:722 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f2/0x390 kernel/kthread.c:389 ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244