INFO: task dhcpcd:4734 blocked for more than 143 seconds. Not tainted 6.8.0-rc4-syzkaller-00212-g40b9385dd8e6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:dhcpcd state:D stack:20504 pid:4734 tgid:4734 ppid:4733 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a3/0xd70 kernel/locking/mutex.c:752 netlink_dump+0xde/0xc80 net/netlink/af_netlink.c:2211 netlink_recvmsg+0x6b9/0x11d0 net/netlink/af_netlink.c:1990 sock_recvmsg_nosec net/socket.c:1046 [inline] sock_recvmsg+0x22f/0x280 net/socket.c:1068 ____sys_recvmsg+0x1db/0x470 net/socket.c:2803 ___sys_recvmsg net/socket.c:2845 [inline] __sys_recvmsg+0x2f0/0x3e0 net/socket.c:2875 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7f3054cd891e RSP: 002b:00007ffe1fdc7628 EFLAGS: 00000246 ORIG_RAX: 000000000000002f RAX: ffffffffffffffda RBX: 00007ffe1fdc8750 RCX: 00007f3054cd891e RDX: 0000000000000000 RSI: 00007ffe1fdc8670 RDI: 0000000000000017 RBP: 00007ffe1fdc86e0 R08: 0000000000000000 R09: 0000000000200000 R10: 00000000000000d1 R11: 0000000000000246 R12: 0000000000000c00 R13: 00007ffe1fdc8654 R14: 00007ffe1fdc8670 R15: 00007ffe1fdc8660 INFO: task syz-executor.1:19503 blocked for more than 143 seconds. Not tainted 6.8.0-rc4-syzkaller-00212-g40b9385dd8e6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:20944 pid:19503 tgid:19503 ppid:1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0x17d1/0x49f0 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0x149/0x260 kernel/sched/core.c:6817 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6874 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x6a3/0xd70 kernel/locking/mutex.c:752 rtnl_lock net/core/rtnetlink.c:79 [inline] rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline] netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367 netlink_sendmsg+0xa3b/0xd70 net/netlink/af_netlink.c:1908 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2199 do_syscall_64+0xf9/0x240 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fb11087fa9c RSP: 002b:00007fff425c2740 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fb1114d4620 RCX: 00007fb11087fa9c RDX: 0000000000000044 RSI: 00007fb1114d4670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fff425c2794 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fb1114d4670 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8e130ae0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614 5 locks held by kworker/u4:7/2910: #0: ffff8880162f4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff8880162f4938 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc9000a6cfd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc9000a6cfd20 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f368a50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf5/0xb90 net/core/net_namespace.c:580 #3: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0xe8/0x9d0 net/core/dev.c:11605 #4: ffffffff8e136340 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x550 kernel/rcu/tree.c:4064 1 lock held by dhcpcd/4734: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xde/0xc80 net/netlink/af_netlink.c:2211 2 locks held by getty/4819: #0: ffff8880300800a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b4/0x1e10 drivers/tty/n_tty.c:2201 3 locks held by kworker/0:4/5142: #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc9000443fd20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc9000443fd20 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104 3 locks held by kworker/1:7/19390: #0: ffff888014c8dd38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8dd38 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900073f7d20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900073f7d20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x91/0xe50 net/wireless/reg.c:2479 3 locks held by kworker/0:2/32372: #0: ffff888029fdbd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888029fdbd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc90005037d20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc90005037d20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4686 2 locks held by kworker/u4:1/17168: 3 locks held by kworker/0:1/19376: #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888014c8c938 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc9000447fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc9000447fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 3 locks held by kworker/1:1/13396: #0: ffff888029fdbd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #0: ffff888029fdbd38 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #1: ffffc900001d7d20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2608 [inline] #1: ffffc900001d7d20 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x1420 kernel/workqueue.c:2706 #2: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4686 1 lock held by syz-executor.3/19387: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_wait_allrefs_any net/core/dev.c:10451 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x821/0xf40 net/core/dev.c:10561 1 lock held by syz-executor.3/19490: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.4/19494: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.0/19498: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.1/19503: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.2/19630: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.2/19634: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.3/19639: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.4/19643: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.0/19646: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.1/19651: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.2/19656: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.3/19660: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.4/19665: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.0/19670: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 1 lock held by syz-executor.1/19674: #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f374fc8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6615 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc4-syzkaller-00212-g40b9385dd8e6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xfaf/0xff0 kernel/hung_task.c:379 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 17168 Comm: kworker/u4:1 Not tainted 6.8.0-rc4-syzkaller-00212-g40b9385dd8e6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:check_wait_context kernel/locking/lockdep.c:4778 [inline] RIP: 0010:__lock_acquire+0x6bc/0x1fd0 kernel/locking/lockdep.c:5087 Code: 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 6c 11 00 00 4a 8d 04 f6 48 89 44 24 48 40 84 ed 4c 8b 74 24 20 0f 84 3c 04 00 00 0f b6 1b <41> 0f b6 04 16 84 c0 0f 85 a0 11 00 00 41 f6 47 01 80 0f 85 21 04 RSP: 0018:ffffc900057f7930 EFLAGS: 00000002 RAX: ffff88808cf36450 RBX: 0000000000000001 RCX: ffffffff817121b9 RDX: dffffc0000000000 RSI: ffff88808cf36400 RDI: ffffffff92c8a420 RBP: 0000000000000002 R08: ffffffff92c8a427 R09: 1ffffffff2591484 R10: dffffc0000000000 R11: fffffbfff2591485 R12: 0000000000000000 R13: ffff88808cf35940 R14: 1ffff110119e6c8e R15: ffff88808cf36470 FS: 0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1a11ad5000 CR3: 000000000df32000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1e3/0x530 kernel/locking/lockdep.c:5754 rcu_lock_acquire include/linux/rcupdate.h:298 [inline] rcu_read_lock include/linux/rcupdate.h:750 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x913/0x1420 kernel/workqueue.c:2706 worker_thread+0xa5f/0x1000 kernel/workqueue.c:2787 kthread+0x2ef/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1b/0x30 arch/x86/entry/entry_64.S:242