INFO: task udevd:5234 blocked for more than 143 seconds. Not tainted 6.11.0-rc5-syzkaller-00193-g4963d2343af8 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:21632 pid:5234 tgid:5234 ppid:4684 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x1800/0x4a60 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2557 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 __flush_workqueue+0x7d6/0x1710 kernel/workqueue.c:3968 nbd_disconnect_and_put+0xaa/0x250 drivers/block/nbd.c:2156 nbd_release+0x103/0x130 drivers/block/nbd.c:1650 bdev_release+0x5e3/0x700 blkdev_release+0x15/0x20 block/fops.c:638 __fput+0x24a/0x8a0 fs/file_table.c:422 __do_sys_close fs/open.c:1566 [inline] __se_sys_close fs/open.c:1551 [inline] __x64_sys_close+0x7f/0x110 fs/open.c:1551 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: 0033:0x7fa23cd170a8 RSP: 002b:00007ffcc15cb988 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 RAX: ffffffffffffffda RBX: 00007fa23d1d8ae0 RCX: 00007fa23cd170a8 RDX: 0000000003938700 RSI: 000000000aba9500 RDI: 0000000000000008 RBP: 0000558589a60e10 R08: 0000000000000001 R09: 90847c93e0c9c272 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000002 R13: 0000558589a48a90 R14: 0000000000000008 R15: 0000558589a3f910 Showing all locks held in the system: 4 locks held by kworker/u8:0/11: 4 locks held by kworker/1:0/25: #0: ffff8880b893e9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560 #1: ffff8880b8928948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:989 #2: ffff8880b8928948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_change+0xfd/0x280 kernel/sched/psi.c:913 #3: ffffffff9a5f47e0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x16d/0x510 lib/debugobjects.c:709 1 lock held by khungtaskd/30: #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626 3 locks held by kworker/u8:6/1098: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90003e0fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90003e0fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276 3 locks held by kworker/u8:7/2962: #0: ffff88802fa6b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff88802fa6b948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc9000978fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc9000978fd00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 #2: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4194 1 lock held by dhcpcd/4898: #0: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101 2 locks held by getty/4980: #0: ffff8880305550a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000312b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211 2 locks held by kworker/u9:5/5238: #0: ffff888025e74948 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline] #0: ffff888025e74948 ((wq_completion)nbd0-recv){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312 #1: ffffc90003a17d00 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline] #1: ffffc90003a17d00 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312 2 locks held by udevd/5234: #0: ffff888025ddc4c8 (&disk->open_mutex){+.+.}-{3:3}, at: bdev_release+0x184/0x700 block/bdev.c:1080 #1: ffff888025e70998 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_disconnect_and_put+0x34/0x250 drivers/block/nbd.c:2148 1 lock held by syz-executor/10995: #0: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 1 lock held by syz-executor/10997: #0: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101 1 lock held by syz-executor/11154: #0: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644 2 locks held by syz-executor/11216: #0: ffffffff8fc7ee50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x4c6/0x7b0 net/core/net_namespace.c:504 #1: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: ip_tunnel_init_net+0x20e/0x710 net/ipv4/ip_tunnel.c:1158 2 locks held by syz.3.1287/11245: #0: ffffffff8fcf1170 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218 #1: ffffffff8fc8ba08 (rtnl_mutex){+.+.}-{3:3}, at: nl80211_pre_doit+0x5f/0x8b0 net/wireless/nl80211.c:16547 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc5-syzkaller-00193-g4963d2343af8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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:223 [inline] watchdog+0xff4/0x1040 kernel/hung_task.c:379 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 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: 7450 Comm: kworker/u8:8 Not tainted 6.11.0-rc5-syzkaller-00193-g4963d2343af8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0xdc/0x550 kernel/locking/lockdep.c:5730 Code: 08 0f 83 f4 02 00 00 89 c3 48 89 d8 48 c1 e8 06 48 8d 3c c5 28 6c 18 90 be 08 00 00 00 e8 0c 0d 8b 00 48 0f a3 1d 9c 9f a8 0e <73> 16 e8 cd f5 09 00 84 c0 75 0d 80 3d c5 6b 92 0e 00 0f 84 f9 02 RSP: 0018:ffffc900034079e0 EFLAGS: 00000257 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff816fcc84 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90186c28 RBP: ffffc90003407b40 R08: ffffffff90186c2f R09: 1ffffffff2030d85 R10: dffffc0000000000 R11: fffffbfff2030d86 R12: 1ffff92000680f44 R13: dffffc0000000000 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000e734000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [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:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244