INFO: task syz.8.141:6937 blocked for more than 143 seconds. Not tainted 6.13.0-rc3-next-20241220-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.8.141 state:D stack:27136 pid:6937 tgid:6929 ppid:6345 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5371 [inline] __schedule+0x189f/0x4c80 kernel/sched/core.c:6758 __schedule_loop kernel/sched/core.c:6835 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6850 d_wait_lookup fs/dcache.c:2477 [inline] d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2559 __lookup_slow+0x117/0x3f0 fs/namei.c:1776 lookup_slow+0x53/0x70 fs/namei.c:1808 walk_component fs/namei.c:2112 [inline] link_path_walk+0x99b/0xea0 fs/namei.c:2477 path_lookupat+0xa9/0x450 fs/namei.c:2633 do_o_path+0x95/0x230 fs/namei.c:3958 path_openat+0x2eaf/0x3580 fs/namei.c:3980 do_filp_open+0x27f/0x4e0 fs/namei.c:4014 do_sys_openat2+0x13e/0x1d0 fs/open.c:1427 do_sys_open fs/open.c:1442 [inline] __do_sys_openat fs/open.c:1458 [inline] __se_sys_openat fs/open.c:1453 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1453 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fa02cb85d29 RSP: 002b:00007fa02d97e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fa02cd76080 RCX: 00007fa02cb85d29 RDX: 0000000000200002 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 00007fa02cc01aa8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fa02cd76080 R15: 00007ffe6d2ff108 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744 3 locks held by kworker/u8:4/62: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000213fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000213fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:281 5 locks held by kworker/u8:9/3584: #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801baf5948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc9000c567c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000c567c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcae690 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x16a/0xd50 net/core/net_namespace.c:602 #3: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xe9/0xaa0 net/core/dev.c:12059 #4: ffffffff8e93d278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:302 [inline] #4: ffffffff8e93d278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x381/0x830 kernel/rcu/tree_exp.h:996 2 locks held by dhcpcd/5500: #0: ffffffff8fd1db10 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: nl80211_pre_doit+0x5f/0x8b0 net/wireless/nl80211.c:16548 2 locks held by getty/5584: #0: ffff888031d210a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211 3 locks held by kworker/1:5/5886: #0: ffff8880b873e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 #1: ffff8880b8728948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987 #2: ffff88807cf21240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x2d1/0x4130 drivers/net/netdevsim/fib.c:1490 1 lock held by syz.8.141/6930: 1 lock held by syz.8.141/6937: #0: ffff8880554a8180 (&type->i_mutex_dir_key#18){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:873 [inline] #0: ffff8880554a8180 (&type->i_mutex_dir_key#18){.+.+}-{4:4}, at: lookup_slow+0x45/0x70 fs/namei.c:1807 3 locks held by kworker/u8:13/8230: #0: ffff888030e51948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff888030e51948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1840 kernel/workqueue.c:3310 #1: ffffc90004ab7c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc90004ab7c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1840 kernel/workqueue.c:3310 #2: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4215 1 lock held by syz-executor/8421: #0: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:128 [inline] #0: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x47e/0x1bd0 net/ipv4/devinet.c:987 2 locks held by syz-executor/8637: #0: ffffffff901af260 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff901af260 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff901af260 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:555 #1: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #1: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:326 [inline] #1: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xce2/0x2210 net/core/rtnetlink.c:4011 3 locks held by syz.7.377/8668: #0: ffff888034c9c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: __tty_ldisc_lock drivers/tty/tty_ldisc.c:289 [inline] #0: ffff888034c9c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:345 [inline] #0: ffff888034c9c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] #0: ffff888034c9c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_release+0xb7/0x200 drivers/tty/tty_ldisc.c:780 #1: ffff88807d2dd0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: __tty_ldisc_lock_nested drivers/tty/tty_ldisc.c:295 [inline] #1: ffff88807d2dd0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair_timeout drivers/tty/tty_ldisc.c:347 [inline] #1: ffff88807d2dd0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_lock_pair drivers/tty/tty_ldisc.c:366 [inline] #1: ffff88807d2dd0a0 (&tty->ldisc_sem/1){+.+.}-{0:0}, at: tty_ldisc_release+0xdb/0x200 drivers/tty/tty_ldisc.c:780 #2: ffffffff8fcbab48 (rtnl_mutex){+.+.}-{4:4}, at: unregister_netdev+0x12/0x30 net/core/dev.c:11607 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc3-next-20241220-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xff6/0x1040 kernel/hung_task.c:397 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 3584 Comm: kworker/u8:9 Not tainted 6.13.0-rc3-next-20241220-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: netns cleanup_net RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:416 Code: fc 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 7c e0 af fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7 RSP: 0018:ffffc9000c567090 EFLAGS: 00000002 RAX: 000000000000005b RBX: ffffffff9a723fe0 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: 0000000000000000 RDI: 0000000000000020 RBP: 0000000000000000 R08: ffffffff8575befb R09: 1ffff11004a1b046 R10: dffffc0000000000 R11: ffffffff8575beb0 R12: dffffc0000000000 R13: ffffffff9a41ef2f R14: 000000000000005b R15: 00000000000003f8 FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3826147ab8 CR3: 0000000024ab2000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial8250_console_write+0x14ed/0x1ed0 drivers/tty/serial/8250/8250_port.c:3413 console_emit_next_record kernel/printk/printk.c:3122 [inline] console_flush_all+0x869/0xeb0 kernel/printk/printk.c:3210 __console_flush_and_unlock kernel/printk/printk.c:3269 [inline] console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309 vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432 _printk+0xd5/0x120 kernel/printk/printk.c:2457 batadv_hardif_disable_interface+0x2b2/0x10e0 net/batman-adv/hard-interface.c:833 batadv_softif_destroy_netlink+0x9c/0x270 net/batman-adv/soft-interface.c:1107 default_device_exit_batch+0x966/0xaa0 net/core/dev.c:12068 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x89d/0xd50 net/core/net_namespace.c:648 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa66/0x1840 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244