R13: 00007ffcd1109a4f R14: 00007f7616bbf300 R15: 0000000000022000 block nbd3: Could not allocate knbd recv work queue. block nbd4: shutting down sockets block nbd3: shutting down sockets block nbd4: Device being setup by another task INFO: task systemd-udevd:15908 blocked for more than 140 seconds. Not tainted 4.14.288-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. systemd-udevd D27464 15908 4635 0x00000304 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 io_schedule+0xb5/0x120 kernel/sched/core.c:5035 wait_on_page_bit_common mm/filemap.c:1025 [inline] wait_on_page_bit+0x241/0x320 mm/filemap.c:1058 wait_on_page_locked include/linux/pagemap.h:527 [inline] wait_on_page_read mm/filemap.c:2680 [inline] do_read_cache_page+0x55f/0xc10 mm/filemap.c:2719 read_mapping_page include/linux/pagemap.h:398 [inline] read_dev_sector+0xbd/0x3c0 block/partition-generic.c:659 read_part_sector block/partitions/check.h:38 [inline] adfspart_check_ICS+0xf6/0xc00 block/partitions/acorn.c:366 check_partition+0x330/0x610 block/partitions/check.c:167 rescan_partitions+0x192/0x800 block/partition-generic.c:523 __blkdev_get+0xd7f/0x1090 fs/block_dev.c:1541 blkdev_get+0x88/0x890 fs/block_dev.c:1611 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772 do_dentry_open+0x44b/0xec0 fs/open.c:777 vfs_open+0x105/0x220 fs/open.c:888 do_last fs/namei.c:3428 [inline] path_openat+0x628/0x2970 fs/namei.c:3569 do_filp_open+0x179/0x3c0 fs/namei.c:3603 do_sys_open+0x296/0x410 fs/open.c:1081 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f05e1039840 RSP: 002b:00007ffee5067fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 000055822cbdb140 RCX: 00007f05e1039840 RDX: 000055822acc4fe3 RSI: 00000000000a0800 RDI: 000055822cbd48f0 RBP: 00007ffee5068160 R08: 000055822acc4670 R09: 0000000000000010 R10: 000055822acc4d0c R11: 0000000000000246 R12: 00007ffee50680b0 R13: 000055822cbd9880 R14: 0000000000000003 R15: 000000000000000e INFO: task syz-executor.2:15925 blocked for more than 140 seconds. Not tainted 4.14.288-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D29128 15925 7993 0x00000006 Call Trace: context_switch kernel/sched/core.c:2811 [inline] __schedule+0x88b/0x1de0 kernel/sched/core.c:3387 schedule+0x8d/0x1b0 kernel/sched/core.c:3431 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489 __mutex_lock_common kernel/locking/mutex.c:833 [inline] __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893 blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 blkdev_close+0x86/0xb0 fs/block_dev.c:1875 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x11f/0x190 kernel/task_work.c:113 get_signal+0x18a3/0x1ca0 kernel/signal.c:2223 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7fdf6afa4199 RSP: 002b:00007fdf698f8168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 00007fdf6b0b7030 RCX: 00007fdf6afa4199 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003 RBP: 00007fdf6affe13b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcd543130f R14: 00007fdf698f8300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1534: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548 1 lock held by in:imklog/7685: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0x1fb/0x2b0 fs/file.c:819 1 lock held by systemd-udevd/15908: #0: (&bdev->bd_mutex){+.+.}, at: [] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455 1 lock held by syz-executor.2/15925: #0: (&bdev->bd_mutex){+.+.}, at: [] blkdev_put+0x27/0x4c0 fs/block_dev.c:1826 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1534 Comm: khungtaskd Not tainted 4.14.288-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x1b2/0x281 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline] watchdog+0x5b9/0xb40 kernel/hung_task.c:274 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 14380 Comm: kworker/u4:1 Not tainted 4.14.288-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022 Workqueue: bat_events batadv_nc_worker task: ffff8880a41542c0 task.stack: ffff8880b4c38000 RIP: 0010:__lock_release kernel/locking/lockdep.c:3804 [inline] RIP: 0010:lock_release+0x38c/0x870 kernel/locking/lockdep.c:4017 RSP: 0018:ffff8880b4c3fbd8 EFLAGS: 00000006 RAX: 0000000000000004 RBX: 1ffff11016987f7e RCX: 1ffff1101482a973 RDX: 1ffffffff17d99b0 RSI: 0000000000000003 RDI: ffff8880a41542c0 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: ffff8880a41542c0 R12: 925544fb9f36ca3b R13: 0000000000000003 R14: ffff8880a41542c0 R15: 0000000000000003 FS: 0000000000000000(0000) GS:ffff8880ba400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4f9fdc0000 CR3: 00000000a1b27000 CR4: 00000000003406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_lock_release include/linux/rcupdate.h:247 [inline] rcu_read_unlock include/linux/rcupdate.h:685 [inline] batadv_nc_process_nc_paths.part.0+0x22e/0x350 net/batman-adv/network-coding.c:709 batadv_nc_process_nc_paths net/batman-adv/network-coding.c:689 [inline] batadv_nc_worker+0x8b8/0xc50 net/batman-adv/network-coding.c:737 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251 kthread+0x30d/0x420 kernel/kthread.c:232 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404 Code: 89 fe 4c 89 f7 e8 f5 ea ff ff 85 c0 75 38 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 41 83 e5 07 48 c1 ea 03 41 83 c5 03 0f b6 04 02 <41> 38 c5 7c 08 84 c0 0f 85 b8 02 00 00 8b 15 11 fc aa 0a 85 d2