INFO: task syz-executor.1:12236 blocked for more than 143 seconds. Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.1 state:D stack:28024 pid:12236 tgid:12233 ppid:8721 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5c70 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6828 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2548 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3de/0x5f0 kernel/sched/completion.c:116 __flush_workqueue+0x39e/0x1200 kernel/workqueue.c:3994 nbd_start_device_ioctl drivers/block/nbd.c:1463 [inline] __nbd_ioctl drivers/block/nbd.c:1524 [inline] nbd_ioctl+0x308/0xfd0 drivers/block/nbd.c:1564 blkdev_ioctl+0x2f7/0x770 block/ioctl.c:640 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl fs/ioctl.c:890 [inline] __x64_sys_ioctl+0x193/0x220 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7fad7d47dda9 RSP: 002b:00007fad7e2560c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fad7d5abf80 RCX: 00007fad7d47dda9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fad7d4ca47a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fad7d5abf80 R15: 00007ffdb3f7a358 Showing all locks held in the system: 1 lock held by khungtaskd/29: #0: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #0: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #0: ffffffff8d7b08e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6614 2 locks held by kworker/u9:0/52: #0: ffff888020291148 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work+0x1296/0x1a60 kernel/workqueue.c:3229 #1: ffffc90000bc7d80 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x906/0x1a60 kernel/workqueue.c:3230 3 locks held by kworker/u8:6/1094: 2 locks held by getty/4816: #0: ffff88802abc60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900015f02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2201 3 locks held by kworker/u9:3/5076: #0: ffff88807e5cb148 ((wq_completion)hci5){+.+.}-{0:0}, at: process_one_work+0x1296/0x1a60 kernel/workqueue.c:3229 #1: ffffc9000357fd80 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x906/0x1a60 kernel/workqueue.c:3230 #2: ffff888064f81060 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x170/0x410 net/bluetooth/hci_sync.c:309 1 lock held by syz-executor.1/12458: 1 lock held by syz-executor.0/14871: #0: ffffffff8f2f63c8 (rtnl_mutex){+.+.}-{3:3}, at: dev_ioctl+0x1a1/0x10a0 net/core/dev_ioctl.c:811 1 lock held by syz-executor.0/14875: 1 lock held by syz-executor.0/14880: #0: ffffffff8f2f63c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8f2f63c8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xe60 net/core/rtnetlink.c:6592 2 locks held by syz-executor.4/14872: #0: ffffffff8f2f63c8 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8f2f63c8 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3e/0x250 drivers/net/tun.c:3498 #1: ffffffff8d7bc4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] #1: ffffffff8d7bc4b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x682/0x7a0 kernel/rcu/tree_exp.h:939 2 locks held by syz-executor.1/14887: 1 lock held by syz-executor.3/14888: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 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+0xf86/0x1210 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 42 Comm: kworker/u8:2 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:debug_smp_processor_id+0xb/0x20 lib/smp_processor_id.c:60 Code: 65 ff 0d 70 75 31 75 e9 40 ff ff ff 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 c7 c6 20 88 6e 8b <48> c7 c7 60 88 6e 8b e9 f9 fe ff ff 66 0f 1f 84 00 00 00 00 00 90 RSP: 0018:ffffc90000b27b08 EFLAGS: 00000283 RAX: 0000000000000000 RBX: ffff88806129fbd8 RCX: ffffffff8a97f5f4 RDX: ffff888019ee8000 RSI: ffffffff8b6e8820 RDI: 0000000000000005 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000002 R12: dffffc0000000000 R13: 0000000000000014 R14: 000000000000007b R15: ffffffff8a97e850 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000e038 CR3: 000000002d7b8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:700 rcu_read_lock include/linux/rcupdate.h:751 [inline] batadv_nc_process_nc_paths.part.0+0x275/0x3e0 net/batman-adv/network-coding.c:687 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:679 [inline] batadv_nc_worker+0xdf1/0x10f0 net/batman-adv/network-coding.c:735 process_one_work+0x9a9/0x1a60 kernel/workqueue.c:3254 process_scheduled_works kernel/workqueue.c:3335 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3416 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243