INFO: task syz.3.1351:12644 blocked for more than 143 seconds. Not tainted 6.14.0-syzkaller-13408-g9f867ba24d36 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.1351 state:D stack:27704 pid:12644 tgid:12642 ppid:5841 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_threads_set_doit+0x698/0xbf0 fs/nfsd/nfsctl.c:1629 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: 0033:0x7f8cab38d169 RSP: 002b:00007f8cac2b7038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f8cab5a5fa0 RCX: 00007f8cab38d169 RDX: 0000000000004000 RSI: 0000200000000480 RDI: 0000000000000004 RBP: 00007f8cab40e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8cab5a5fa0 R15: 00007ffef25e5368 Showing all locks held in the system: 4 locks held by kworker/1:0/24: 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 2 locks held by syz-executor/5837: #0: ffff88802a1f20e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88802a1f20e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88802a1f20e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline] #0: ffff88802a1f20e0 (&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/5842: #0: ffff888047d780e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff888047d780e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff888047d780e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline] #0: ffff888047d780e0 (&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/1:1/11634: #0: ffff88801b480d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000483fd18 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 2 locks held by syz.1.1339/12590: #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.3.1351/12644: #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.4.1462/13247: #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.5.1472/13290: #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/13404: #0: ffff88804b8200e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock fs/super.c:56 [inline] #0: ffff88804b8200e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline] #0: ffff88804b8200e0 (&type->s_umount_key#49){+.+.}-{4:4}, at: deactivate_super fs/super.c:505 [inline] #0: ffff88804b8200e0 (&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/u8:22/13437: #0: ffff8880b8439f18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:605 #1: ffffc900048afd18 ((work_completion)(&(&bat_priv->nc.work)->work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 1 lock held by syz-executor/13463: 2 locks held by getty/14049: #0: ffff88814e0800a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90004ab32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by kworker/u8:27/14053: 2 locks held by syz.8.1629/14148: 2 locks held by syz.8.1629/14167: #0: ffffffff9012d9a8 (rtnl_mutex){+.+.}-{4:4}, at: ppp_release+0x167/0x230 drivers/net/ppp/ppp_generic.c:420 #1: ffffffff8e3ccab8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336 1 lock held by syz-executor/14168: #0: ffffffff9012d9a8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff9012d9a8 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x1540 net/ipv4/devinet.c:979 ============================================= NMI backtrace for cpu 0 CPU: 0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 13437 Comm: kworker/u8:22 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:lock_release+0x6/0x2f0 kernel/locking/lockdep.c:5874 Code: 44 24 1c 44 8b 4c 24 18 4c 8b 54 24 10 44 8b 5c 24 0c eb 8c 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 <41> 56 41 55 41 54 49 89 f4 53 48 89 fb 48 83 ec 18 65 48 8b 05 f9 RSP: 0018:ffffc900048afa98 EFLAGS: 00000206 RAX: 0000000000000000 RBX: ffff88805d77ddc0 RCX: ffffffff8198687c RDX: ffff888026889e00 RSI: ffffffff8b3d5d44 RDI: ffff88805d77ddd8 RBP: dffffc0000000000 R08: 0000000000000001 R09: fffff52000915f49 R10: 0000000000000003 R11: 0000000000000000 R12: ffffffff8b3d60f0 R13: ffff88805d77ddc0 R14: ffff88805d760d80 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888124ab9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fff78182ff8 CR3: 000000003b128000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline] _raw_spin_unlock_bh+0x16/0x30 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] batadv_nc_purge_paths+0x1d4/0x3a0 net/batman-adv/network-coding.c:471 batadv_nc_worker+0x921/0x1030 net/batman-adv/network-coding.c:720 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