INFO: task syz-executor287:16264 can't die for more than 143 seconds.
task:syz-executor287 state:D stack:26632 pid:16264 ppid:  6555 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4965 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6246
 schedule+0xd2/0x260 kernel/sched/core.c:6319
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 dev_deactivate_many+0x710/0xc60 net/sched/sch_generic.c:1302
 dev_deactivate+0xe9/0x1b0 net/sched/sch_generic.c:1312
 qdisc_graft+0xdac/0x1260 net/sched/sch_api.c:1061
 tc_modify_qdisc+0xb92/0x1980 net/sched/sch_api.c:1671
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2491
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x86d/0xda0 net/netlink/af_netlink.c:1916
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fde84903f49
RSP: 002b:00007fff536d0b78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000098579 RCX: 00007fde84903f49
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fff536d0d18 R09: 00007fff536d0d18
R10: 00007fff536d0d18 R11: 0000000000000246 R12: 00007fff536d0b8c
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
3 locks held by kworker/1:0/20:
 #0: ffff888021dcf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888021dcf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888021dcf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
 #0: ffff888021dcf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline]
 #0: ffff888021dcf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline]
 #0: ffff888021dcf938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2268
 #1: ffffc90000da7db0 ((addr_chk_work).work){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2272
 #2: ffffffff8d2fcb68 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0xa/0x20 net/ipv6/addrconf.c:4590
1 lock held by khungtaskd/27:
 #0: ffffffff8bb835a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
1 lock held by syz-executor287/16264:
 #0: ffffffff8d2fcb68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
 #0: ffffffff8d2fcb68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5569

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