INFO: task kworker/R-ipv6_:3170 blocked for more than 145 seconds. Not tainted 6.14.0-syzkaller-05877-g1a9239bb4253 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/R-ipv6_ state:D stack:26256 pid:3170 tgid:3170 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:5366 [inline] __schedule+0x1b18/0x50e0 kernel/sched/core.c:6747 __schedule_loop kernel/sched/core.c:6824 [inline] schedule+0x163/0x360 kernel/sched/core.c:6839 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6896 __mutex_lock_common kernel/locking/mutex.c:664 [inline] __mutex_lock+0x7fa/0x1000 kernel/locking/mutex.c:732 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_dad_work+0x110/0x16a0 net/ipv6/addrconf.c:4190 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319 rescuer_thread+0x652/0xf90 kernel/workqueue.c:3496 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 2 locks held by kthreadd/2: 4 locks held by kworker/0:0/9: 4 locks held by kworker/0:1/10: 3 locks held by kworker/u8:1/13: 1 lock held by kworker/R-mm_pe/14: 3 locks held by kworker/1:0/24: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc900001e7c60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900001e7c60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2531 1 lock held by khungtaskd/31: #0: ffffffff8ed3a260 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8ed3a260 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8ed3a260 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6761 4 locks held by kworker/u8:2/36: #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801bef6148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90000ad7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90000ad7c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900cb2d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608 #3: ffffffff900d7f08 (rtnl_mutex){+.+.}-{4:4}, at: netdev_wait_allrefs_any net/core/dev.c:11186 [inline] #3: ffffffff900d7f08 (rtnl_mutex){+.+.}-{4:4}, at: netdev_run_todo+0x821/0xf30 net/core/dev.c:11298 5 locks held by kworker/1:1/47: 4 locks held by kworker/u8:4/63: 3 locks held by kworker/1:2/976: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000398fc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000398fc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2531 3 locks held by kworker/0:2/979: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90003967c60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003967c60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2531 3 locks held by kworker/R-ipv6_/3170: #0: ffff88814c753148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88814c753148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc9000be47be0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000be47be0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff900d7f08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff900d7f08 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x110/0x16a0 net/ipv6/addrconf.c:4190 4 locks held by dhcpcd/5500: 2 locks held by getty/5585: #0: ffff8880361920a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x53d/0x16b0 drivers/tty/n_tty.c:2211 2 locks held by syz-executor/5824: 1 lock held by syz-executor/5834: #0: ffffffff8ed3f778 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] #0: ffffffff8ed3f778 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998 3 locks held by kworker/0:3/5837: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90004b5fc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004b5fc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2531 3 locks held by kworker/1:3/5852: 3 locks held by kworker/0:4/5888: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90004dcfc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004dcfc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2531 3 locks held by kworker/0:5/5889: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319 #1: ffffc90004ddfc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90004ddfc60 ((work_completion)(&(&ovs_net->masks_rebalance)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319 #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_lock net/openvswitch/datapath.c:108 [inline] #2: ffffffff9040d868 (ovs_mutex){+.+.}-{4:4}, at: ovs_dp_masks_rebalance+0x2f/0xe0 net/openvswitch/datapath.c:2531 3 locks held by kworker/0:6/5890: #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801b080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319