INFO: task kworker/u4:6:12250 blocked for more than 143 seconds. Not tainted 6.1.0-rc5-syzkaller-00018-g59d0d52c30d4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:6 state:D stack:22936 pid:12250 ppid:2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5191 [inline] __schedule+0x8fc/0xda0 kernel/sched/core.c:6503 schedule+0xcb/0x190 kernel/sched/core.c:6579 rxrpc_destroy_all_calls+0x595/0x690 net/rxrpc/call_object.c:736 rxrpc_exit_net+0x6a/0xc0 net/rxrpc/net_ns.c:123 ops_exit_list net/core/net_namespace.c:169 [inline] cleanup_net+0x758/0xc50 net/core/net_namespace.c:601 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Showing all locks held in the system: 3 locks held by kworker/u4:0/9: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d323ff0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d3247f0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x30/0xd00 kernel/rcu/tasks.h:507 2 locks held by ksoftirqd/0/15: 1 lock held by khungtaskd/28: #0: ffffffff8d323e20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by khugepaged/35: #0: ffffffff8d3c9208 (lock#3){+.+.}-{3:3}, at: __lru_add_drain_all+0x66/0x800 mm/swap.c:873 3 locks held by kworker/1:2/156: #0: ffff88814abc0d38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x796/0xd10 kernel/workqueue.c:2262 #1: ffffc90002f1fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0xd10 kernel/workqueue.c:2264 #2: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd8/0x16e0 net/ipv6/addrconf.c:4083 5 locks held by syslogd/2979: 1 lock held by klogd/2986: 1 lock held by dhcpcd/3210: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2cd/0x1ab0 net/ipv4/devinet.c:1070 2 locks held by getty/3306: #0: ffff8880282a9098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6e8/0x1e50 drivers/tty/n_tty.c:2177 4 locks held by syz-fuzzer/3649: 3 locks held by kworker/0:7/3724: #0: ffff888012864d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x796/0xd10 kernel/workqueue.c:2262 #1: ffffc900044cfd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0xd10 kernel/workqueue.c:2264 #2: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263 3 locks held by kworker/0:10/4439: 3 locks held by kworker/u4:6/12250: #0: ffff8880129c3138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x796/0xd10 kernel/workqueue.c:2262 #1: ffffc900152f7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0xd10 kernel/workqueue.c:2264 #2: ffffffff8e471b50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf0/0xc50 net/core/net_namespace.c:563 1 lock held by syz-executor.2/16413: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.3/16417: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.1/16425: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.4/16427: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.5/16429: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 2 locks held by syz-executor.0/16430: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 #1: ffffffff8d3293b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline] #1: ffffffff8d3293b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a6/0x890 kernel/rcu/tree_exp.h:946 1 lock held by syz-executor.2/16523: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.3/16527: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.1/16531: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.4/16536: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.0/16538: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 1 lock held by syz-executor.5/16539: #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline] #0: ffffffff8e47de88 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x75d/0xe90 net/core/rtnetlink.c:6088 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.0-rc5-syzkaller-00018-g59d0d52c30d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e3/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x19b/0x3e0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xcf5/0xd40 kernel/hung_task.c:377 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 16544 Comm: syz-executor.2 Not tainted 6.1.0-rc5-syzkaller-00018-g59d0d52c30d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:__lock_acquire+0x412/0x1f60 kernel/locking/lockdep.c:4996 Code: 6c 24 10 83 7d 00 00 0f 95 c0 09 c3 c1 e3 0d 44 09 fb 8b 44 24 44 c1 e0 0f 0f b7 c0 09 d8 8b 74 24 28 83 e6 03 c1 e6 10 09 c6 <41> 83 e4 01 41 c1 e4 12 31 c9 83 7c 24 60 00 0f 95 c1 c1 e1 13 41 RSP: 0018:ffffc900037ff4a8 EFLAGS: 00000002 RAX: 00000000000000a7 RBX: 00000000000000a7 RCX: ffffffff81d51ec5 RDX: dffffc0000000000 RSI: 00000000000000a7 RDI: ffffffff8d3f9ac0 RBP: ffff88803c732774 R08: 0000000000000001 R09: 0000000000000000 R10: fffffbfff1d2299e R11: 1ffffffff1d2299d R12: 0000000000000001 R13: ffff88803c731d40 R14: 0000000000000000 R15: 00000000000000a7 FS: 000055555575a400(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555575b6e8 CR3: 0000000034847000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1a7/0x400 kernel/locking/lockdep.c:5668 __fs_reclaim_acquire mm/page_alloc.c:4679 [inline] fs_reclaim_acquire+0x82/0x120 mm/page_alloc.c:4693 might_alloc include/linux/sched/mm.h:271 [inline] prepare_alloc_pages+0x145/0x5a0 mm/page_alloc.c:5325 __alloc_pages+0x161/0x560 mm/page_alloc.c:5544 vm_area_alloc_pages mm/vmalloc.c:2975 [inline] __vmalloc_area_node mm/vmalloc.c:3043 [inline] __vmalloc_node_range+0x8f4/0x1290 mm/vmalloc.c:3213 alloc_thread_stack_node+0x307/0x500 kernel/fork.c:311 dup_task_struct+0x8b/0x490 kernel/fork.c:974 copy_process+0x637/0x3fc0 kernel/fork.c:2084 kernel_clone+0x227/0x640 kernel/fork.c:2671 __do_sys_clone kernel/fork.c:2812 [inline] __se_sys_clone kernel/fork.c:2796 [inline] __x64_sys_clone+0x276/0x2e0 kernel/fork.c:2796 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe498e8ca61 Code: 48 85 ff 74 3d 48 85 f6 74 38 48 83 ee 10 48 89 4e 08 48 89 3e 48 89 d7 4c 89 c2 4d 89 c8 4c 8b 54 24 08 b8 38 00 00 00 0f 05 <48> 85 c0 7c 13 74 01 c3 31 ed 58 5f ff d0 48 89 c7 b8 3c 00 00 00 RSP: 002b:00007ffcee154b08 EFLAGS: 00000206 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 00007fe498000700 RCX: 00007fe498e8ca61 RDX: 00007fe4980009d0 RSI: 00007fe4980002f0 RDI: 00000000003d0f00 RBP: 00007ffcee154bc0 R08: 00007fe498000700 R09: 00007fe498000700 R10: 00007fe4980009d0 R11: 0000000000000206 R12: 00007ffcee154bbe R13: 00007ffcee154bbf R14: 00007fe498000300 R15: 0000000000802000