INFO: task kworker/0:2:1052 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:2 state:D stack:21680 pid: 1052 ppid: 2 flags:0x00004000 Workqueue: ipv6_addrconf addrconf_dad_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 addrconf_dad_work+0xdb/0x1d10 net/ipv6/addrconf.c:4047 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 INFO: task kworker/1:7:8520 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/1:7 state:D stack:21432 pid: 8520 ppid: 2 flags:0x00004000 Workqueue: events linkwatch_event Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 linkwatch_event+0xa/0x50 net/core/link_watch.c:251 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 INFO: task kworker/0:4:32354 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:4 state:D stack:24952 pid:32354 ppid: 2 flags:0x00004000 Workqueue: events switchdev_deferred_process_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 INFO: task syz-executor.5:331 blocked for more than 144 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:20272 pid: 331 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 netlink_rcv_skb+0x200/0x470 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x814/0x9f0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0xa29/0xe50 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] __sys_sendto+0x560/0x720 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fbaf219b69c RSP: 002b:00007ffdec019fd0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fbaf3225320 RCX: 00007fbaf219b69c RDX: 0000000000000028 RSI: 00007fbaf3225370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffdec01a024 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fbaf3225370 R14: 0000000000000003 R15: 0000000000000000 INFO: task syz-executor.0:344 blocked for more than 144 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:20896 pid: 344 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 netlink_rcv_skb+0x200/0x470 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x814/0x9f0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0xa29/0xe50 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] __sys_sendto+0x560/0x720 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f24b161869c RSP: 002b:00007ffe15bfbdc0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f24b26a2320 RCX: 00007f24b161869c RDX: 0000000000000050 RSI: 00007f24b26a2370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe15bfbe14 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007f24b26a2370 R14: 0000000000000003 R15: 0000000000000000 INFO: task syz-executor.2:345 blocked for more than 144 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:21296 pid: 345 ppid: 1 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common+0xdff/0x2550 kernel/locking/mutex.c:669 __mutex_lock kernel/locking/mutex.c:729 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:743 rtnl_lock net/core/rtnetlink.c:72 [inline] rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 netlink_rcv_skb+0x200/0x470 net/netlink/af_netlink.c:2504 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x814/0x9f0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0xa29/0xe50 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] __sys_sendto+0x560/0x720 net/socket.c:2036 __do_sys_sendto net/socket.c:2048 [inline] __se_sys_sendto net/socket.c:2044 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2044 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fb86229369c RSP: 002b:00007fffe9d73030 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fb86331d320 RCX: 00007fb86229369c RDX: 0000000000000028 RSI: 00007fb86331d370 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fffe9d73084 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007fb86331d370 R14: 0000000000000003 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8c91c1c0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 3 locks held by kworker/0:2/1052: #0: ffff888025d2bd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc90004857d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xdb/0x1d10 net/ipv6/addrconf.c:4047 1 lock held by in:imklog/6227: #0: ffff888079e92d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:990 2 locks held by agetty/6219: #0: ffff888016851098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc900013a82e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6c5/0x1c60 drivers/tty/n_tty.c:2113 3 locks held by kworker/1:7/8520: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc90017a5fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251 5 locks held by kworker/u4:12/21781: 3 locks held by kworker/0:4/32354: #0: ffff888011064d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ca/0x1140 #1: ffffc900081c7d20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x808/0x1140 kernel/workqueue.c:2272 #2: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74 1 lock held by syz-executor.5/331: #0: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 1 lock held by syz-executor.0/344: #0: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 1 lock held by syz-executor.2/345: #0: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline] #0: ffffffff8d95bc48 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x8ed/0xe60 net/core/rtnetlink.c:5569 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-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:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x16a/0x280 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+0xc54/0xca0 kernel/hung_task.c:295 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 21781 Comm: kworker/u4:12 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net RIP: 0010:rcu_is_watching+0x70/0xb0 kernel/rcu/tree.c:1122 Code: 03 00 49 03 1e 48 89 df be 04 00 00 00 e8 c8 de 60 00 48 89 d8 48 c1 e8 03 42 8a 04 38 84 c0 75 1a 8b 03 65 ff 0d 18 fb 94 7e <74> 08 24 01 5b 41 5e 41 5f c3 e8 b1 62 93 ff eb f1 89 d9 80 e1 07 RSP: 0018:ffffc900052cf3a0 EFLAGS: 00000282 RAX: 0000000000124e25 RBX: ffff8880b9c32508 RCX: ffffffff816cf498 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff8880b9c32508 RBP: ffffc900052cf448 R08: dffffc0000000000 R09: ffffed10173864a2 R10: ffffed10173864a2 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8c3897d0 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc12d32c000 CR3: 000000000c68e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_sched_held+0x6b/0x130 kernel/rcu/update.c:123 trace_lock_acquire+0x59/0x190 include/trace/events/lock.h:13 lock_acquire+0xa5/0x4d0 kernel/locking/lockdep.c:5596 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:363 [inline] nf_conntrack_lock net/netfilter/nf_conntrack_core.c:87 [inline] get_next_corpse net/netfilter/nf_conntrack_core.c:2230 [inline] nf_ct_iterate_cleanup+0xf8/0x3f0 net/netfilter/nf_conntrack_core.c:2275 nf_ct_iterate_cleanup_net+0x172/0x1e0 net/netfilter/nf_conntrack_core.c:2363 masq_device_event+0x9b/0xd0 net/netfilter/nf_nat_masquerade.c:88 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xe7/0x170 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:1996 [inline] call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] dev_close_many+0x38b/0x540 net/core/dev.c:1597 unregister_netdevice_many+0x53a/0x19e0 net/core/dev.c:11020 default_device_exit_batch+0x44b/0x4b0 net/core/dev.c:11573 ops_exit_list net/core/net_namespace.c:171 [inline] cleanup_net+0x7ec/0xc50 net/core/net_namespace.c:591 process_one_work+0x853/0x1140 kernel/workqueue.c:2297 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 ---------------- Code disassembly (best guess): 0: 03 00 add (%rax),%eax 2: 49 03 1e add (%r14),%rbx 5: 48 89 df mov %rbx,%rdi 8: be 04 00 00 00 mov $0x4,%esi d: e8 c8 de 60 00 callq 0x60deda 12: 48 89 d8 mov %rbx,%rax 15: 48 c1 e8 03 shr $0x3,%rax 19: 42 8a 04 38 mov (%rax,%r15,1),%al 1d: 84 c0 test %al,%al 1f: 75 1a jne 0x3b 21: 8b 03 mov (%rbx),%eax 23: 65 ff 0d 18 fb 94 7e decl %gs:0x7e94fb18(%rip) # 0x7e94fb42 * 2a: 74 08 je 0x34 <-- trapping instruction 2c: 24 01 and $0x1,%al 2e: 5b pop %rbx 2f: 41 5e pop %r14 31: 41 5f pop %r15 33: c3 retq 34: e8 b1 62 93 ff callq 0xff9362ea 39: eb f1 jmp 0x2c 3b: 89 d9 mov %ebx,%ecx 3d: 80 e1 07 and $0x7,%cl