INFO: task kworker/u4:3:28471 blocked for more than 140 seconds. Not tainted 4.19.211-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:3 D25536 28471 2 0x80000000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3517 schedule+0x8d/0x1b0 kernel/sched/core.c:3561 schedule_timeout+0x92d/0xfe0 kernel/time/timer.c:1794 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common+0x29c/0x470 kernel/sched/completion.c:115 __synchronize_srcu+0x124/0x210 kernel/rcu/srcutree.c:936 fsnotify_mark_destroy_workfn+0xfd/0x340 fs/notify/mark.c:795 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 process_scheduled_works kernel/workqueue.c:2212 [inline] worker_thread+0x82b/0x1130 kernel/workqueue.c:2298 kthread+0x33f/0x460 kernel/kthread.c:259 device ipvlan15 entered promiscuous mode ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Showing all locks held in the system: 2 locks held by kworker/u4:0/7: 2 locks held by ksoftirqd/1/18: 2 locks held by kworker/u4:1/23: #0: 00000000748c07d1 ((wq_completion)"events_unbound"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000e807ab3d (connector_reaper_work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 1 lock held by khungtaskd/1571: #0: 000000004557d3ca (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441 1 lock held by in:imklog/7822: #0: 00000000a1775200 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 2 locks held by agetty/8052: #0: 00000000fdc13d1c (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: 00000000fba59ba0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x217/0x1950 drivers/tty/n_tty.c:2154 3 locks held by kworker/0:1/19485: #0: 00000000cbb3c113 ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000b2688d85 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 #2: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: addrconf_dad_work+0x9c/0x10a0 net/ipv6/addrconf.c:3989 2 locks held by kworker/u4:3/28471: #0: 00000000748c07d1 ((wq_completion)"events_unbound"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 00000000c5a36743 ((reaper_work).work){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 2 locks held by kworker/0:3/18541: #0: 0000000044c87559 ((wq_completion)"rcu_gp"){+.+.}, at: process_one_work+0x767/0x1570 kernel/workqueue.c:2124 #1: 000000006fc85453 ((work_completion)(&rew.rew_work)){+.+.}, at: process_one_work+0x79c/0x1570 kernel/workqueue.c:2128 5 locks held by kworker/1:1/10894: 2 locks held by syz-executor.3/2315: #0: 000000006b75f144 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #0: 000000006b75f144 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598 #1: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: ip6mr_sk_done+0xe0/0x370 net/ipv6/ip6mr.c:1564 2 locks held by syz-executor.3/2325: #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 #1: 0000000054c9a3ed (rcu_preempt_state.exp_mutex){+.+.}, at: exp_funnel_lock kernel/rcu/tree_exp.h:297 [inline] #1: 0000000054c9a3ed (rcu_preempt_state.exp_mutex){+.+.}, at: _synchronize_rcu_expedited+0x4dc/0x6f0 kernel/rcu/tree_exp.h:667 2 locks held by syz-executor.4/2316: #0: 00000000a591b3f2 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000a591b3f2 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598 #1: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: ip6mr_sk_done+0xe0/0x370 net/ipv6/ip6mr.c:1564 2 locks held by syz-executor.1/2317: #0: 00000000eefd76d3 (&sb->s_type->i_mutex_key#13){+.+.}, at: inode_lock include/linux/fs.h:748 [inline] #0: 00000000eefd76d3 (&sb->s_type->i_mutex_key#13){+.+.}, at: __sock_release+0x86/0x2a0 net/socket.c:598 #1: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: ip6mr_sk_done+0xe0/0x370 net/ipv6/ip6mr.c:1564 1 lock held by syz-executor.1/2324: #0: 00000000868ed180 (rcu_preempt_state.barrier_mutex){+.+.}, at: _rcu_barrier+0x59/0x3e0 kernel/rcu/tree.c:3430 1 lock held by syz-executor.2/2343: #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 1 lock held by syz-executor.2/2364: #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 1 lock held by syz-executor.0/2345: #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 1 lock held by syz-executor.0/2349: #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline] #0: 000000008e0c59f0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x3fe/0xb80 net/core/rtnetlink.c:4779 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1571 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 10894 Comm: kworker/1:1 Not tainted 4.19.211-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events ipvlan_process_multicast RIP: 0010:__read_once_size include/linux/compiler.h:263 [inline] RIP: 0010:__in6_dev_get include/net/addrconf.h:340 [inline] RIP: 0010:fib6_ignore_linkdown net/ipv6/route.c:655 [inline] RIP: 0010:find_match.part.0+0x84/0x1530 net/ipv6/route.c:673 Code: 4d 85 f6 0f 84 1c 01 00 00 e8 e8 fe 5a fa 49 8d be 40 03 00 00 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 30 12 00 00 4d 8b b6 40 03 00 00 e8 3a 17 49 fa 31 ff 89 c6 RSP: 0018:ffff8880ba107680 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffff88805cc7a0c0 RCX: ffff8880ba107800 RDX: 1ffff11012cc9d10 RSI: ffffffff87078688 RDI: ffff88809664e880 RBP: ffff8880ba107728 R08: ffff88809f356c00 R09: ffff8880ba1077f0 R10: 0000000000000005 R11: 0000000000000000 R12: 0000000000000003 R13: 0000000000000093 R14: ffff88809664e540 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f93e976f718 CR3: 00000000a44a6000 CR4: 00000000003426e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: find_match net/ipv6/route.c:670 [inline] find_rr_leaf net/ipv6/route.c:719 [inline] rt6_select net/ipv6/route.c:769 [inline] fib6_table_lookup+0x4c2/0xf40 net/ipv6/route.c:1876 ip6_pol_route+0x180/0x1270 net/ipv6/route.c:1909 fib6_rule_lookup+0x10b/0x4e0 net/ipv6/fib6_rules.c:118 ip6_route_input_lookup net/ipv6/route.c:1990 [inline] ip6_route_input+0x6c0/0xaa0 net/ipv6/route.c:2125 ip6_rcv_finish_core.constprop.0.isra.0+0xd7/0x550 net/ipv6/ip6_input.c:63 ip6_rcv_finish+0x176/0x2f0 net/ipv6/ip6_input.c:74 NF_HOOK include/linux/netfilter.h:289 [inline] ipv6_rcv+0xf2/0x3f0 net/ipv6/ip6_input.c:273 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:4954 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5066 process_backlog+0x241/0x700 net/core/dev.c:5849 napi_poll net/core/dev.c:6280 [inline] net_rx_action+0x4ac/0xfb0 net/core/dev.c:6346 __do_softirq+0x265/0x980 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1092 do_softirq.part.0+0x160/0x1c0 kernel/softirq.c:336 do_softirq kernel/softirq.c:328 [inline] __local_bh_enable_ip+0x20e/0x270 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] ipvlan_process_multicast+0x79c/0xcb0 drivers/net/ipvlan/ipvlan_core.c:284 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 ---------------- Code disassembly (best guess): 0: 4d 85 f6 test %r14,%r14 3: 0f 84 1c 01 00 00 je 0x125 9: e8 e8 fe 5a fa callq 0xfa5afef6 e: 49 8d be 40 03 00 00 lea 0x340(%r14),%rdi 15: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1c: fc ff df 1f: 48 89 fa mov %rdi,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) * 2a: 0f 85 30 12 00 00 jne 0x1260 <-- trapping instruction 30: 4d 8b b6 40 03 00 00 mov 0x340(%r14),%r14 37: e8 3a 17 49 fa callq 0xfa491776 3c: 31 ff xor %edi,%edi 3e: 89 c6 mov %eax,%esi