INFO: task syz.0.1618:11015 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1618 state:D stack:0 pid:11015 tgid:11010 ppid:4711 task_flags:0x400140 flags:0x00800001 Call trace: __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:810 (T) context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1bec/0x2dcc kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x140/0x218 kernel/sched/core.c:7283 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x4e4/0xef8 kernel/locking/mutex.c:820 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:873 genl_lock net/netlink/genetlink.c:35 [inline] genl_op_lock net/netlink/genetlink.c:60 [inline] genl_rcv_msg+0xec/0x620 net/netlink/genetlink.c:1208 netlink_rcv_skb+0x22c/0x410 net/netlink/af_netlink.c:2555 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x610/0x800 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x63c/0x920 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg+0xc8/0x138 net/socket.c:802 __sys_sendto+0x254/0x338 net/socket.c:2265 __do_sys_sendto net/socket.c:2272 [inline] __se_sys_sendto net/socket.c:2268 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2268 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594 INFO: task kworker/u8:10:11027 blocked for more than 145 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:10 state:D stack:0 pid:11027 tgid:11027 ppid:2 task_flags:0x4208060 flags:0x00000010 Workqueue: ipv6_addrconf addrconf_verify_work Call trace: __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:810 (T) context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1bec/0x2dcc kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x140/0x218 kernel/sched/core.c:7283 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x4e4/0xef8 kernel/locking/mutex.c:820 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:873 rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 rtnl_net_lock include/linux/rtnetlink.h:130 [inline] addrconf_verify_work+0x20/0x3c net/ipv6/addrconf.c:4746 process_one_work kernel/workqueue.c:3314 [inline] process_scheduled_works+0x79c/0x1098 kernel/workqueue.c:3397 worker_thread+0x754/0xba0 kernel/workqueue.c:3478 kthread+0x2f8/0x3c8 kernel/kthread.c:436 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:842 Showing all locks held in the system: 1 lock held by kthreadd/2: 2 locks held by kworker/0:0/9: 3 locks held by kworker/u8:0/12: 2 locks held by kworker/u8:1/15: 2 locks held by kworker/1:1/26: 1 lock held by khungtaskd/31: #0: ffff800088b67320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffff800088b67320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffff800088b67320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6775 3 locks held by kworker/u8:2/39: 3 locks held by kworker/u8:3/40: 1 lock held by kworker/u8:4/131: #0: ffff800088a0e120 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x40/0x344 kernel/workqueue.c:2729 3 locks held by kworker/u8:5/307: 4 locks held by kworker/1:2/868: 3 locks held by kworker/u8:6/1416: 2 locks held by kworker/0:2/1510: 2 locks held by kworker/0:3/1519: 4 locks held by kworker/R-bat_e/2855: 3 locks held by kworker/u8:7/3503: 4 locks held by kworker/u8:8/3576: 1 lock held by klogd/4329: 2 locks held by udevd/4340: 3 locks held by dhcpcd/4395: 2 locks held by crond/4470: 2 locks held by getty/4486: #0: ffff0000ca31d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80009232e2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x354/0xf84 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/4694: 1 lock held by syz-executor/4707: 1 lock held by syz-executor/4714: 1 lock held by kworker/R-wg-cr/4783: #0: ffff800088a0e120 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x40/0x344 kernel/workqueue.c:2729 1 lock held by kworker/R-wg-cr/4786: 1 lock held by kworker/R-wg-cr/4787: #0: ffff800088a0e120 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x40/0x344 kernel/workqueue.c:2729 5 locks held by kworker/1:4/4807: 3 locks held by kworker/1:8/4824: 4 locks held by kworker/0:5/4848: 4 locks held by kworker/u8:9/4918: 2 locks held by syz-executor/5364: 1 lock held by kworker/R-bond1/6366: #0: ffff800088a0e120 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x40/0x344 kernel/workqueue.c:2729 1 lock held by syz.0.642/7564: #0: ffff800089c3d880 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 1 lock held by kworker/R-bond2/8665: #0: ffff800088a0e120 (wq_pool_attach_mutex){+.+.}-{4:4}, at: worker_attach_to_pool+0x40/0x344 kernel/workqueue.c:2729 4 locks held by syz.6.1617/11008: 2 locks held by syz.0.1618/11015: #0: ffff800089ca4428 (cb_lock){++++}-{4:4}, at: genl_rcv+0x28/0x50 net/netlink/genetlink.c:1217 #1: ffff800089ca4260 (genl_mutex){+.+.}-{4:4}, at: genl_lock net/netlink/genetlink.c:35 [inline] #1: ffff800089ca4260 (genl_mutex){+.+.}-{4:4}, at: genl_op_lock net/netlink/genetlink.c:60 [inline] #1: ffff800089ca4260 (genl_mutex){+.+.}-{4:4}, at: genl_rcv_msg+0xec/0x620 net/netlink/genetlink.c:1208 3 locks held by kworker/u8:10/11027: #0: ffff0000ce75c940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #0: ffff0000ce75c940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x748/0x1098 kernel/workqueue.c:3397 #1: ffff800093287c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline] #1: ffff800093287c40 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x750/0x1098 kernel/workqueue.c:3397 #2: ffff800089c3d880 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:80 3 locks held by kworker/u8:11/11028: 3 locks held by kworker/u8:12/11029: 4 locks held by kworker/u8:13/11030: 4 locks held by kworker/u8:14/11031: 3 locks held by kworker/u8:15/11032: 4 locks held by kworker/u8:16/11033: =============================================