INFO: task khugepaged:1156 blocked for more than 143 seconds. Not tainted 5.7.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. khugepaged D23728 1156 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3430 [inline] __schedule+0x8f3/0x1fc0 kernel/sched/core.c:4156 schedule+0xd0/0x2a0 kernel/sched/core.c:4231 schedule_timeout+0x55b/0x850 kernel/time/timer.c:1873 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x16a/0x270 kernel/sched/completion.c:138 __flush_work+0x4fd/0xa80 kernel/workqueue.c:3045 lru_add_drain_all+0x3f6/0x5c0 mm/swap.c:808 khugepaged_do_scan mm/khugepaged.c:2177 [inline] khugepaged+0xfa/0x3f80 mm/khugepaged.c:2238 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Showing all locks held in the system: 2 locks held by kworker/1:0/17: #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: __write_once_size include/linux/compiler.h:279 [inline] #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:615 [inline] #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:642 [inline] #0: ffff8880aa036538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 kernel/workqueue.c:2239 #1: ffffc90000d8fdc0 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 kernel/workqueue.c:2243 1 lock held by khungtaskd/1144: #0: ffffffff899bdd80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by khugepaged/1156: #0: ffffffff89a419a8 (lock#4){+.+.}-{3:3}, at: lru_add_drain_all+0x59/0x5c0 mm/swap.c:779 1 lock held by in:imklog/6535: #0: ffff8880a643d870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by kworker/u4:8/9943: 4 locks held by kworker/0:4/5819: 1 lock held by syz-executor.3/17707: #0: ffffffff899c22e8 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x44/0x4b0 kernel/rcu/tree.c:3578 1 lock held by syz-executor.5/17760: #0: ffff888050448468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:86 [inline] #0: ffff888050448468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x54c/0x16e0 fs/pipe.c:538 2 locks held by syz-executor.5/17761: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1144 Comm: khungtaskd Not tainted 5.7.0-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1e6/0x221 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa8c/0x1010 kernel/hung_task.c:289 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5819 Comm: kworker/0:4 Not tainted 5.7.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events ipvlan_process_multicast RIP: 0010:__lock_is_held kernel/locking/lockdep.c:4733 [inline] RIP: 0010:lock_is_held_type+0x1a1/0x360 kernel/locking/lockdep.c:4996 Code: c7 01 84 c0 74 08 3c 03 0f 8e 63 01 00 00 44 3b bd c8 08 00 00 0f 8d ea 00 00 00 49 63 c7 48 89 de 48 8d 04 80 4d 8d 74 c5 00 <4c> 89 f7 e8 57 f9 ff ff 85 c0 74 c3 83 7c 24 04 ff 41 bc 01 00 00 RSP: 0018:ffffc900000074c0 EFLAGS: 00000097 RAX: 0000000000000014 RBX: ffffffff8a597468 RCX: ffffffff86d73225 RDX: 0000000000000000 RSI: ffffffff8a597468 RDI: ffff888014770bea RBP: ffff888014770280 R08: ffff888014770280 R09: ffffc90000007770 R10: ffff8880ae638c9b R11: ffffed1015cc7193 R12: ffffed10028ee169 R13: ffff888014770b50 R14: ffff888014770bf0 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000b90004 CR3: 00000000a885e000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:425 [inline] lockdep_rtnl_is_held+0x17/0x30 net/core/rtnetlink.c:137 __in6_dev_get include/net/addrconf.h:310 [inline] ip6_ignore_linkdown include/net/addrconf.h:401 [inline] find_match+0x2d0/0xc90 net/ipv6/route.c:749 __find_rr_leaf+0x137/0x980 net/ipv6/route.c:837 find_rr_leaf net/ipv6/route.c:858 [inline] rt6_select net/ipv6/route.c:902 [inline] fib6_table_lookup+0x629/0xcc0 net/ipv6/route.c:2189 ip6_pol_route+0x1c9/0xc20 net/ipv6/route.c:2225 fib6_rule_lookup+0x112/0x750 net/ipv6/fib6_rules.c:114 ip6_route_input+0x5f0/0xa40 net/ipv6/route.c:2464 ip6_rcv_finish_core.isra.0+0x168/0x580 net/ipv6/ip6_input.c:63 ip6_rcv_finish+0x176/0x310 net/ipv6/ip6_input.c:74 NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ipv6_rcv+0xf8/0x3f0 net/ipv6/ip6_input.c:307 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5268 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5382 process_backlog+0x21e/0x7a0 net/core/dev.c:6226 napi_poll net/core/dev.c:6671 [inline] net_rx_action+0x4c2/0x1070 net/core/dev.c:6739 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082 do_softirq.part.0+0x10f/0x160 kernel/softirq.c:337 do_softirq kernel/softirq.c:329 [inline] __local_bh_enable_ip+0x20e/0x270 kernel/softirq.c:189 local_bh_enable include/linux/bottom_half.h:32 [inline] ipvlan_process_multicast+0x7e6/0xca0 drivers/net/ipvlan/ipvlan_core.c:279 process_one_work+0x965/0x16a0 kernel/workqueue.c:2268 worker_thread+0x96/0xe20 kernel/workqueue.c:2414 kthread+0x388/0x470 kernel/kthread.c:268 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351