INFO: task kworker/u4:6:12123 blocked for more than 143 seconds. Not tainted 5.8.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/u4:6 D25016 12123 2 0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 schedule_timeout+0x1d8/0x250 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+0x163/0x260 kernel/sched/completion.c:138 start_unregistering fs/proc/proc_sysctl.c:288 [inline] drop_sysctl_table+0x41d/0x4e0 fs/proc/proc_sysctl.c:1639 unregister_sysctl_table fs/proc/proc_sysctl.c:1681 [inline] unregister_sysctl_table+0xbd/0x190 fs/proc/proc_sysctl.c:1656 ip_vs_control_net_cleanup_sysctl net/netfilter/ipvs/ip_vs_ctl.c:4077 [inline] ip_vs_control_net_cleanup+0x239/0x4f0 net/netfilter/ipvs/ip_vs_ctl.c:4146 __ip_vs_cleanup_batch+0x95/0x120 net/netfilter/ipvs/ip_vs_core.c:2421 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:189 cleanup_net+0x4ea/0xa00 net/core/net_namespace.c:603 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 INFO: task syz-executor.5:13093 blocked for more than 143 seconds. Not tainted 5.8.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28752 13093 7381 0x00000004 Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1808 bcm_init+0x1a3/0x210 net/can/bcm.c:1451 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3ca/0x740 net/socket.c:1428 sock_create net/socket.c:1479 [inline] __sys_socket+0xef/0x200 net/socket.c:1521 __do_sys_socket net/socket.c:1530 [inline] __se_sys_socket net/socket.c:1528 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1528 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007f028ad71c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000508420 RCX: 000000000045cb29 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000bb6 R14: 00000000004ce18b R15: 00007f028ad726d4 INFO: task syz-executor.5:13127 blocked for more than 143 seconds. Not tainted 5.8.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28752 13127 7381 0x00000004 Call Trace: context_switch kernel/sched/core.c:3453 [inline] __schedule+0x8e1/0x1eb0 kernel/sched/core.c:4178 schedule+0xd0/0x2a0 kernel/sched/core.c:4253 rwsem_down_write_slowpath+0x603/0xc60 kernel/locking/rwsem.c:1235 __down_write kernel/locking/rwsem.c:1389 [inline] down_write+0x137/0x150 kernel/locking/rwsem.c:1532 register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1808 bcm_init+0x1a3/0x210 net/can/bcm.c:1451 can_create+0x27c/0x4d0 net/can/af_can.c:168 __sock_create+0x3ca/0x740 net/socket.c:1428 sock_create net/socket.c:1479 [inline] __sys_socket+0xef/0x200 net/socket.c:1521 __do_sys_socket net/socket.c:1530 [inline] __se_sys_socket net/socket.c:1528 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1528 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45cb29 Code: Bad RIP value. RSP: 002b:00007f028ad2fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000508420 RCX: 000000000045cb29 RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d RBP: 000000000078c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000bb6 R14: 00000000004ce18b R15: 00007f028ad306d4 Showing all locks held in the system: 1 lock held by khungtaskd/1139: #0: ffffffff89bc1180 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5779 1 lock held by in:imklog/6533: #0: ffff8880a6e0bb30 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by rs:main Q:Reg/6535: 2 locks held by agetty/6782: #0: ffff8880908fa098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000ff02e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 2 locks held by agetty/6784: #0: ffff8880a6ee1098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267 #1: ffffc90000fe02e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156 3 locks held by kworker/u4:6/12123: #0: ffff8880a97c9138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8880a97c9138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline] #0: ffff8880a97c9138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff8880a97c9138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline] #0: ffff8880a97c9138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline] #0: ffff8880a97c9138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x82b/0x1670 kernel/workqueue.c:2240 #1: ffffc90001bc7da8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x85f/0x1670 kernel/workqueue.c:2244 #2: ffffffff8a7a62f0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa00 net/core/net_namespace.c:565 1 lock held by syz-executor.5/13093: #0: ffffffff8a7a62f0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1808 1 lock held by syz-executor.5/13127: #0: ffffffff8a7a62f0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1e/0x260 net/core/dev.c:1808 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1139 Comm: khungtaskd Not tainted 5.8.0-rc3-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+0x18f/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xd7d/0x1000 kernel/hung_task.c:295 kthread+0x3b5/0x4a0 kernel/kthread.c:291 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3908 Comm: systemd-journal Not tainted 5.8.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_local_irq_restore+0x34/0x50 arch/x86/include/asm/paravirt.h:766 Code: fb 48 ba 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 75 18 48 83 3d a9 e8 5b 08 00 74 0c 48 89 df 57 9d 0f 1f 44 00 00 5b 0f 0b 48 c7 c7 40 e0 b4 89 e8 2d 15 5a 00 eb da 90 66 2e 0f 1f RSP: 0018:ffffc900015f7da8 EFLAGS: 00000282 RAX: 1ffffffff1369c08 RBX: 0000000000000000 RCX: ffffffff81bca10f RDX: dffffc0000000000 RSI: 00000000ffffffff RDI: 0000000000000282 RBP: ffff8880a6d92500 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8880a6d92dd0 R14: dffffc0000000000 R15: 0000000000000282 FS: 00007f9b19cf98c0(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9b172e2000 CR3: 00000000a6ca9000 CR4: 00000000001426f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held_type+0xb0/0xe0 kernel/locking/lockdep.c:4998 lock_is_held include/linux/lockdep.h:425 [inline] ___might_sleep+0x22b/0x2f0 kernel/sched/core.c:6865 dput+0x4d/0xbc0 fs/dcache.c:862 path_put+0x2d/0x60 fs/namei.c:496 do_faccessat+0x31c/0x820 fs/open.c:457 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:359 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f9b18fb59c7 Code: Bad RIP value. RSP: 002b:00007fff67d4e468 EFLAGS: 00000246 ORIG_RAX: 0000000000000015 RAX: ffffffffffffffda RBX: 00007fff67d51490 RCX: 00007f9b18fb59c7 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00005610c66629a3 RBP: 00007fff67d4e5b0 R08: 00005610c66583e5 R09: 0000000000000018 R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00005610c675d8c0 R15: 00007fff67d4eaa0