INFO: task khugepaged:1663 blocked for more than 143 seconds. Not tainted 5.14.0-rc7-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:khugepaged state:D stack:23888 pid: 1663 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4695 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:6026 schedule+0xd3/0x270 kernel/sched/core.c:6105 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 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+0x176/0x280 kernel/sched/completion.c:138 __flush_work+0x50e/0xad0 kernel/workqueue.c:3053 __lru_add_drain_all+0x3fd/0x760 mm/swap.c:842 khugepaged_do_scan mm/khugepaged.c:2214 [inline] khugepaged+0x10f/0x5590 mm/khugepaged.c:2275 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Showing all locks held in the system: 3 locks held by kworker/u4:3/56: #0: ffff88814011b138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff88814011b138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:620 [inline] #0: ffff88814011b138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff88814011b138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:617 [inline] #0: ffff88814011b138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ffff88814011b138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x871/0x1630 kernel/workqueue.c:2247 #1: ffffc90000f8fdb0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1630 kernel/workqueue.c:2251 #2: ffffffff8d0b9e50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:557 1 lock held by khungtaskd/1656: #0: ffffffff8b97c280 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by khugepaged/1663: #0: ffffffff8ba5f328 (lock#6){+.+.}-{3:3}, at: __lru_add_drain_all+0x65/0x760 mm/swap.c:791 1 lock held by in:imklog/8148: #0: ffff88803352b270 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 3 locks held by kworker/0:6/9789: 2 locks held by syz-executor.5/20737: #0: ffffffff8d0b9e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:470 #1: ffffffff8d0cd4a8 (rtnl_mutex){+.+.}-{3:3}, at: cangw_pernet_exit+0xe/0x20 net/can/gw.c:1244 2 locks held by syz-executor.3/20742: #0: ffffffff8d0b9e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:470 #1: ffffffff8b9856e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline] #1: ffffffff8b9856e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d5/0x620 kernel/rcu/tree_exp.h:837 1 lock held by syz-executor.2/20764: #0: ffffffff8d0b9e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:470 2 locks held by syz-executor.4/20765: #0: ffffffff8d0b9e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:470 #1: ffffffff8d0cd4a8 (rtnl_mutex){+.+.}-{3:3}, at: ipmr_rules_exit+0x20/0x2a0 net/ipv4/ipmr.c:274 1 lock held by syz-executor.0/20773: #0: ffffffff8d0b9e50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f5/0x760 net/core/net_namespace.c:470 2 locks held by syz-executor.1/20925: #0: ffffffff8d0cd4a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d0cd4a8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3be/0xb80 net/core/rtnetlink.c:5572 #1: ffffffff8b9856e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline] #1: ffffffff8b9856e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x4fc/0x620 kernel/rcu/tree_exp.h:837 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1656 Comm: khungtaskd Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xd0a/0xfc0 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 9789 Comm: kworker/0:6 Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events ipvlan_process_multicast RIP: 0010:check_preemption_disabled+0x9/0x140 lib/smp_processor_id.c:13 Code: 6e f8 65 48 8b 3c 25 40 f0 01 00 e8 f1 87 27 f8 eb 99 0f 1f 44 00 00 0f 0b e9 23 ff ff ff cc cc cc 41 56 41 55 49 89 f5 41 54 <55> 48 89 fd 53 0f 1f 44 00 00 65 44 8b 25 dd 1e d7 76 65 8b 1d 6e RSP: 0018:ffffc90000007580 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffff8881489210a0 RCX: 0000000000000100 RDX: ffff888021ab54c0 RSI: ffffffff89e3b880 RDI: ffffffff89e3b8c0 RBP: ffffc90000007630 R08: 0000000000000001 R09: 0000000000000000 R10: ffffffff87d4df64 R11: 0000000000000000 R12: 0000000000000003 R13: ffffffff89e3b880 R14: 00000000000002a4 R15: ffff88814ded5000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556ad0f44160 CR3: 000000002c519000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs kernel/rcu/tree.c:339 [inline] rcu_is_watching+0xe/0xc0 kernel/rcu/tree.c:1160 rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_held+0x18/0x40 kernel/rcu/update.c:309 __in6_dev_get include/net/addrconf.h:313 [inline] ip6_ignore_linkdown include/net/addrconf.h:404 [inline] find_match.part.0+0x257/0xcc0 net/ipv6/route.c:738 find_match net/ipv6/route.c:825 [inline] __find_rr_leaf+0x17f/0xd20 net/ipv6/route.c:826 find_rr_leaf net/ipv6/route.c:847 [inline] rt6_select net/ipv6/route.c:891 [inline] fib6_table_lookup+0x649/0xa20 net/ipv6/route.c:2182 ip6_pol_route+0x1c5/0x11d0 net/ipv6/route.c:2218 pol_lookup_func include/net/ip6_fib.h:579 [inline] fib6_rule_lookup+0x111/0x6f0 net/ipv6/fib6_rules.c:115 ip6_route_input_lookup net/ipv6/route.c:2288 [inline] ip6_route_input+0x63c/0xb30 net/ipv6/route.c:2584 ip6_rcv_finish_core.constprop.0.isra.0+0x168/0x570 net/ipv6/ip6_input.c:63 ip6_rcv_finish net/ipv6/ip6_input.c:74 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] NF_HOOK include/linux/netfilter.h:301 [inline] ipv6_rcv+0x229/0x3c0 net/ipv6/ip6_input.c:297 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5498 __netif_receive_skb+0x24/0x1b0 net/core/dev.c:5612 process_backlog+0x2a5/0x6c0 net/core/dev.c:6492 __napi_poll+0xaf/0x440 net/core/dev.c:7047 napi_poll net/core/dev.c:7114 [inline] net_rx_action+0x801/0xb40 net/core/dev.c:7201 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558 do_softirq.part.0+0xde/0x130 kernel/softirq.c:459 do_softirq kernel/softirq.c:451 [inline] __local_bh_enable_ip+0x102/0x120 kernel/softirq.c:383 local_bh_enable include/linux/bottom_half.h:32 [inline] ipvlan_process_multicast+0x821/0xd80 drivers/net/ipvlan/ipvlan_core.c:279 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 6e outsb %ds:(%rsi),(%dx) 1: f8 clc 2: 65 48 8b 3c 25 40 f0 mov %gs:0x1f040,%rdi 9: 01 00 b: e8 f1 87 27 f8 callq 0xf8278801 10: eb 99 jmp 0xffffffab 12: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 17: 0f 0b ud2 19: e9 23 ff ff ff jmpq 0xffffff41 1e: cc int3 1f: cc int3 20: cc int3 21: 41 56 push %r14 23: 41 55 push %r13 25: 49 89 f5 mov %rsi,%r13 28: 41 54 push %r12 * 2a: 55 push %rbp <-- trapping instruction 2b: 48 89 fd mov %rdi,%rbp 2e: 53 push %rbx 2f: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 34: 65 44 8b 25 dd 1e d7 mov %gs:0x76d71edd(%rip),%r12d # 0x76d71f19 3b: 76 3c: 65 gs 3d: 8b .byte 0x8b 3e: 1d .byte 0x1d 3f: 6e outsb %ds:(%rsi),(%dx)