====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ udevd/21721 is trying to acquire lock: ffff000019bc3870 (&nsock->tx_lock){+.+.}-{4:4}, at: nbd_handle_cmd drivers/block/nbd.c:1140 [inline] ffff000019bc3870 (&nsock->tx_lock){+.+.}-{4:4}, at: nbd_queue_rq+0x2cc/0xb54 drivers/block/nbd.c:1204 but task is already holding lock: ffff000013a4e178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xa8/0xb54 drivers/block/nbd.c:1196 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&cmd->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x144/0xffc kernel/locking/mutex.c:760 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:812 nbd_queue_rq+0xa8/0xb54 drivers/block/nbd.c:1196 blk_mq_dispatch_rq_list+0x2d0/0x161c block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xa44/0xe24 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0x7c/0x100 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x1e4/0x500 block/blk-mq.c:2358 blk_mq_dispatch_list+0x348/0xa50 block/blk-mq.c:2919 blk_mq_flush_plug_list block/blk-mq.c:2967 [inline] blk_mq_flush_plug_list+0xe8/0x508 block/blk-mq.c:2939 __blk_flush_plug+0x208/0x3b8 block/blk-core.c:1220 blk_finish_plug block/blk-core.c:1247 [inline] blk_finish_plug block/blk-core.c:1244 [inline] __submit_bio+0x3a4/0x4ac block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x59c/0xa8c block/blk-core.c:751 submit_bio_noacct+0x858/0x18f8 block/blk-core.c:874 submit_bio+0x32c/0x5f0 block/blk-core.c:916 submit_bh_wbc+0x310/0x480 fs/buffer.c:2824 submit_bh fs/buffer.c:2829 [inline] block_read_full_folio+0x26c/0x640 fs/buffer.c:2447 blkdev_read_folio+0x1c/0x28 block/fops.c:491 filemap_read_folio+0xac/0x1fc mm/filemap.c:2413 do_read_cache_folio+0x1c4/0x480 mm/filemap.c:3957 read_cache_folio+0x44/0x6c mm/filemap.c:3989 read_mapping_folio include/linux/pagemap.h:991 [inline] read_part_sector+0xac/0x5f4 block/partitions/core.c:722 read_lba+0x15c/0x2ec block/partitions/efi.c:248 find_valid_gpt block/partitions/efi.c:603 [inline] efi_partition+0x1dc/0x2154 block/partitions/efi.c:720 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x508/0xf0c block/partitions/core.c:693 blkdev_get_whole+0x144/0x1e4 block/bdev.c:748 bdev_open+0x1dc/0xa84 block/bdev.c:957 blkdev_open+0x1d4/0x324 block/fops.c:691 do_dentry_open+0x6a4/0x103c fs/open.c:965 vfs_open+0x5c/0x2fc fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x1490/0x24b4 fs/namei.c:4046 do_filp_open+0x184/0x360 fs/namei.c:4073 do_sys_openat2+0xe0/0x160 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1461 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x50/0x1a0 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #5 (set->srcu){.+.+}-{0:0}: srcu_lock_sync include/linux/srcu.h:173 [inline] __synchronize_srcu+0xa8/0x268 kernel/rcu/srcutree.c:1429 synchronize_srcu_expedited kernel/rcu/srcutree.c:1469 [inline] synchronize_srcu+0x12c/0x370 kernel/rcu/srcutree.c:1525 blk_mq_wait_quiesce_done block/blk-mq.c:283 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:280 [inline] blk_mq_quiesce_queue block/blk-mq.c:303 [inline] blk_mq_quiesce_queue+0xf4/0x15c block/blk-mq.c:298 elevator_switch+0x11c/0x414 block/elevator.c:588 elevator_change+0x294/0x424 block/elevator.c:690 elevator_set_default+0x22c/0x2ac block/elevator.c:766 blk_register_queue+0x278/0x3ac block/blk-sysfs.c:904 __add_disk+0x518/0xb80 block/genhd.c:528 add_disk_fwnode+0x114/0x4c0 block/genhd.c:597 device_add_disk+0x14/0x20 block/genhd.c:627 add_disk include/linux/blkdev.h:774 [inline] nbd_dev_add+0x5f0/0x9c0 drivers/block/nbd.c:1973 nbd_init+0xd4/0x1a8 drivers/block/nbd.c:2680 do_one_initcall+0x130/0x7f0 init/main.c:1269 do_initcall_level init/main.c:1331 [inline] do_initcalls init/main.c:1347 [inline] do_basic_setup init/main.c:1366 [inline] kernel_init_freeable+0x48c/0x70c init/main.c:1579 kernel_init+0x24/0x1dc init/main.c:1469 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 -> #4 (&q->elevator_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x144/0xffc kernel/locking/mutex.c:760 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:812 elevator_change+0x130/0x424 block/elevator.c:688 elevator_set_none+0x90/0xe4 block/elevator.c:781 blk_mq_elv_switch_none block/blk-mq.c:5023 [inline] __blk_mq_update_nr_hw_queues+0x3b4/0xd38 block/blk-mq.c:5066 blk_mq_update_nr_hw_queues+0x44/0x68 block/blk-mq.c:5124 nbd_start_device+0x128/0xa38 drivers/block/nbd.c:1478 nbd_genl_connect+0xcb4/0x14c4 drivers/block/nbd.c:2228 genl_family_rcv_msg_doit+0x1b8/0x280 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x3ec/0x5bc net/netlink/genetlink.c:1210 netlink_rcv_skb+0x19c/0x338 net/netlink/af_netlink.c:2552 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x424/0x700 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x644/0xa54 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0xc8/0x168 net/socket.c:729 ____sys_sendmsg+0x500/0x764 net/socket.c:2614 ___sys_sendmsg+0x11c/0x19c net/socket.c:2668 __sys_sendmsg+0x114/0x19c net/socket.c:2700 __compat_sys_sendmsg net/compat.c:346 [inline] __do_compat_sys_sendmsg net/compat.c:353 [inline] __se_compat_sys_sendmsg net/compat.c:350 [inline] __arm64_compat_sys_sendmsg+0x74/0xa4 net/compat.c:350 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc_compat+0x40/0x68 arch/arm64/kernel/syscall.c:157 el0_svc_compat+0x4c/0x184 arch/arm64/kernel/entry-common.c:1029 el0t_32_sync_handler+0x88/0xac arch/arm64/kernel/entry-common.c:1047 el0t_32_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:601 -> #3 (&q->q_usage_counter(io)#33){++++}-{0:0}: blk_alloc_queue+0x538/0x644 block/blk-core.c:461 blk_mq_alloc_queue+0x144/0x220 block/blk-mq.c:4400 __blk_mq_alloc_disk+0x20/0x1a4 block/blk-mq.c:4447 nbd_dev_add+0x3c0/0x9c0 drivers/block/nbd.c:1943 nbd_init+0xd4/0x1a8 drivers/block/nbd.c:2680 do_one_initcall+0x130/0x7f0 init/main.c:1269 do_initcall_level init/main.c:1331 [inline] do_initcalls init/main.c:1347 [inline] do_basic_setup init/main.c:1366 [inline] kernel_init_freeable+0x48c/0x70c init/main.c:1579 kernel_init+0x24/0x1dc init/main.c:1469 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 -> #2 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:4234 [inline] fs_reclaim_acquire+0x138/0x160 mm/page_alloc.c:4248 might_alloc include/linux/sched/mm.h:318 [inline] slab_pre_alloc_hook mm/slub.c:4131 [inline] slab_alloc_node mm/slub.c:4209 [inline] kmem_cache_alloc_node_noprof+0x64/0x3b8 mm/slub.c:4281 __alloc_skb+0x208/0x2f0 net/core/skbuff.c:659 alloc_skb_fclone include/linux/skbuff.h:1386 [inline] tcp_stream_alloc_skb+0x2c/0x450 net/ipv4/tcp.c:892 tcp_sendmsg_locked+0xf34/0x39e8 net/ipv4/tcp.c:1198 tcp_sendmsg+0x38/0x60 net/ipv4/tcp.c:1393 inet_sendmsg+0x90/0xd4 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:714 [inline] __sock_sendmsg+0xc8/0x168 net/socket.c:729 sock_write_iter+0x1cc/0x300 net/socket.c:1179 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x7bc/0xb88 fs/read_write.c:686 ksys_write+0x18c/0x1d8 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __arm64_sys_write+0x6c/0x9c fs/read_write.c:746 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x50/0x1a0 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 -> #1 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x38/0xe8 net/core/sock.c:3733 lock_sock include/net/sock.h:1667 [inline] inet_shutdown+0x50/0x348 net/ipv4/af_inet.c:905 kernel_sock_shutdown+0x54/0x84 net/socket.c:3701 nbd_mark_nsock_dead+0x100/0x534 drivers/block/nbd.c:318 sock_shutdown+0x134/0x234 drivers/block/nbd.c:411 nbd_clear_sock drivers/block/nbd.c:1416 [inline] nbd_config_put+0x154/0x5b0 drivers/block/nbd.c:1440 nbd_release+0x7c/0x128 drivers/block/nbd.c:1745 blkdev_put_whole+0x98/0xf0 block/bdev.c:721 bdev_release+0x2a4/0x510 block/bdev.c:1144 blkdev_release+0x14/0x24 block/fops.c:699 __fput+0x2c8/0x954 fs/file_table.c:468 ____fput+0x14/0x20 fs/file_table.c:496 task_work_run+0x128/0x210 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] do_notify_resume+0x1d8/0x260 arch/arm64/kernel/entry-common.c:155 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline] el0_svc_compat+0x104/0x184 arch/arm64/kernel/entry-common.c:1030 el0t_32_sync_handler+0x88/0xac arch/arm64/kernel/entry-common.c:1047 el0t_32_sync+0x19c/0x1a0 arch/arm64/kernel/entry.S:601 -> #0 (&nsock->tx_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1638/0x2380 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x144/0xffc kernel/locking/mutex.c:760 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:812 nbd_handle_cmd drivers/block/nbd.c:1140 [inline] nbd_queue_rq+0x2cc/0xb54 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x2d0/0x161c block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xa44/0xe24 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0x7c/0x100 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x1e4/0x500 block/blk-mq.c:2358 blk_mq_dispatch_list+0x348/0xa50 block/blk-mq.c:2919 blk_mq_flush_plug_list block/blk-mq.c:2967 [inline] blk_mq_flush_plug_list+0xe8/0x508 block/blk-mq.c:2939 __blk_flush_plug+0x208/0x3b8 block/blk-core.c:1220 blk_finish_plug block/blk-core.c:1247 [inline] blk_finish_plug block/blk-core.c:1244 [inline] __submit_bio+0x3a4/0x4ac block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x59c/0xa8c block/blk-core.c:751 submit_bio_noacct+0x858/0x18f8 block/blk-core.c:874 submit_bio+0x32c/0x5f0 block/blk-core.c:916 submit_bh_wbc+0x310/0x480 fs/buffer.c:2824 submit_bh fs/buffer.c:2829 [inline] block_read_full_folio+0x26c/0x640 fs/buffer.c:2447 blkdev_read_folio+0x1c/0x28 block/fops.c:491 filemap_read_folio+0xac/0x1fc mm/filemap.c:2413 do_read_cache_folio+0x1c4/0x480 mm/filemap.c:3957 read_cache_folio+0x44/0x6c mm/filemap.c:3989 read_mapping_folio include/linux/pagemap.h:991 [inline] read_part_sector+0xac/0x5f4 block/partitions/core.c:722 read_lba+0x15c/0x2ec block/partitions/efi.c:248 find_valid_gpt block/partitions/efi.c:603 [inline] efi_partition+0x1dc/0x2154 block/partitions/efi.c:720 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x508/0xf0c block/partitions/core.c:693 blkdev_get_whole+0x144/0x1e4 block/bdev.c:748 bdev_open+0x1dc/0xa84 block/bdev.c:957 blkdev_open+0x1d4/0x324 block/fops.c:691 do_dentry_open+0x6a4/0x103c fs/open.c:965 vfs_open+0x5c/0x2fc fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x1490/0x24b4 fs/namei.c:4046 do_filp_open+0x184/0x360 fs/namei.c:4073 do_sys_openat2+0xe0/0x160 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1461 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x50/0x1a0 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 other info that might help us debug this: Chain exists of: &nsock->tx_lock --> set->srcu --> &cmd->lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&cmd->lock); lock(set->srcu); lock(&cmd->lock); lock(&nsock->tx_lock); *** DEADLOCK *** 3 locks held by udevd/21721: #0: ffff000014b6d358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x2c4/0xa84 block/bdev.c:945 #1: ffff000014689710 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x19c/0x500 block/blk-mq.c:2358 #2: ffff000013a4e178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xa8/0xb54 drivers/block/nbd.c:1196 stack backtrace: CPU: 1 UID: 0 PID: 21721 Comm: udevd Not tainted syzkaller #0 PREEMPT Hardware name: linux,dummy-virt (DT) Call trace: show_stack+0x18/0x24 arch/arm64/kernel/stacktrace.c:499 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xa4/0xf4 lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x28c/0x370 kernel/locking/lockdep.c:2043 check_noncircular+0x168/0x17c kernel/locking/lockdep.c:2175 check_prev_add kernel/locking/lockdep.c:3165 [inline] check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x1638/0x2380 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x310/0x38c kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:598 [inline] __mutex_lock+0x144/0xffc kernel/locking/mutex.c:760 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:812 nbd_handle_cmd drivers/block/nbd.c:1140 [inline] nbd_queue_rq+0x2cc/0xb54 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x2d0/0x161c block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline] __blk_mq_sched_dispatch_requests+0xa44/0xe24 block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0x7c/0x100 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x1e4/0x500 block/blk-mq.c:2358 blk_mq_dispatch_list+0x348/0xa50 block/blk-mq.c:2919 blk_mq_flush_plug_list block/blk-mq.c:2967 [inline] blk_mq_flush_plug_list+0xe8/0x508 block/blk-mq.c:2939 __blk_flush_plug+0x208/0x3b8 block/blk-core.c:1220 blk_finish_plug block/blk-core.c:1247 [inline] blk_finish_plug block/blk-core.c:1244 [inline] __submit_bio+0x3a4/0x4ac block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x59c/0xa8c block/blk-core.c:751 submit_bio_noacct+0x858/0x18f8 block/blk-core.c:874 submit_bio+0x32c/0x5f0 block/blk-core.c:916 submit_bh_wbc+0x310/0x480 fs/buffer.c:2824 submit_bh fs/buffer.c:2829 [inline] block_read_full_folio+0x26c/0x640 fs/buffer.c:2447 blkdev_read_folio+0x1c/0x28 block/fops.c:491 filemap_read_folio+0xac/0x1fc mm/filemap.c:2413 do_read_cache_folio+0x1c4/0x480 mm/filemap.c:3957 read_cache_folio+0x44/0x6c mm/filemap.c:3989 read_mapping_folio include/linux/pagemap.h:991 [inline] read_part_sector+0xac/0x5f4 block/partitions/core.c:722 read_lba+0x15c/0x2ec block/partitions/efi.c:248 find_valid_gpt block/partitions/efi.c:603 [inline] efi_partition+0x1dc/0x2154 block/partitions/efi.c:720 check_partition block/partitions/core.c:141 [inline] blk_add_partitions block/partitions/core.c:589 [inline] bdev_disk_changed+0x508/0xf0c block/partitions/core.c:693 blkdev_get_whole+0x144/0x1e4 block/bdev.c:748 bdev_open+0x1dc/0xa84 block/bdev.c:957 blkdev_open+0x1d4/0x324 block/fops.c:691 do_dentry_open+0x6a4/0x103c fs/open.c:965 vfs_open+0x5c/0x2fc fs/open.c:1095 do_open fs/namei.c:3887 [inline] path_openat+0x1490/0x24b4 fs/namei.c:4046 do_filp_open+0x184/0x360 fs/namei.c:4073 do_sys_openat2+0xe0/0x160 fs/open.c:1435 do_sys_open fs/open.c:1450 [inline] __do_sys_openat fs/open.c:1466 [inline] __se_sys_openat fs/open.c:1461 [inline] __arm64_sys_openat+0x12c/0x1bc fs/open.c:1461 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x50/0x1a0 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0xa0/0xe4 arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 block nbd0: Dead connection, failed to find a fallback block nbd0: shutting down sockets I/O error, dev nbd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 0, async page read I/O error, dev nbd0, sector 2 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 1, async page read I/O error, dev nbd0, sector 4 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 2, async page read I/O error, dev nbd0, sector 6 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 3, async page read I/O error, dev nbd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 0, async page read I/O error, dev nbd0, sector 2 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 1, async page read I/O error, dev nbd0, sector 4 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 2, async page read I/O error, dev nbd0, sector 6 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 3, async page read nbd0: unable to read partition table I/O error, dev nbd0, sector 0 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 0, async page read I/O error, dev nbd0, sector 2 op 0x0:(READ) flags 0x0 phys_seg 1 prio class 2 Buffer I/O error on dev nbd0, logical block 1, async page read nbd0: unable to read partition table