====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.1.1649/8329 is trying to acquire lock: ffffaf801f4e1c70 (&nsock->tx_lock){+.+.}-{4:4}, at: nbd_handle_cmd drivers/block/nbd.c:1143 [inline] ffffaf801f4e1c70 (&nsock->tx_lock){+.+.}-{4:4}, at: nbd_queue_rq+0x372/0xe44 drivers/block/nbd.c:1207 but task is already holding lock: ffffaf802ff08180 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc4/0xe44 drivers/block/nbd.c:1199 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&cmd->lock){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x164/0x1890 kernel/locking/mutex.c:776 mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:828 nbd_queue_rq+0xc4/0xe44 drivers/block/nbd.c:1199 blk_mq_dispatch_rq_list+0x3cc/0x1ac0 block/blk-mq.c:2148 __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+0xe12/0x13cc block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xb2/0x174 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x274/0x6ec block/blk-mq.c:2386 blk_mq_dispatch_list+0x53e/0x1430 block/blk-mq.c:2949 blk_mq_flush_plug_list block/blk-mq.c:2997 [inline] blk_mq_flush_plug_list+0x114/0x55c block/blk-mq.c:2969 __blk_flush_plug+0x270/0x464 block/blk-core.c:1230 blk_finish_plug block/blk-core.c:1257 [inline] blk_finish_plug block/blk-core.c:1254 [inline] __submit_bio+0x42e/0x504 block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x458/0xdf4 block/blk-core.c:753 submit_bio_noacct+0x6fe/0x2170 block/blk-core.c:884 submit_bio+0xb6/0x5b8 block/blk-core.c:926 blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline] submit_bh_wbc+0x428/0x5c0 fs/buffer.c:2821 submit_bh fs/buffer.c:2826 [inline] block_read_full_folio+0x396/0x788 fs/buffer.c:2444 blkdev_read_folio+0x26/0x30 block/fops.c:494 filemap_read_folio+0xc2/0x270 mm/filemap.c:2501 do_read_cache_folio+0x22e/0x518 mm/filemap.c:4101 read_cache_folio+0x4e/0x68 mm/filemap.c:4133 read_mapping_folio include/linux/pagemap.h:1028 [inline] read_part_sector+0xbc/0x408 block/partitions/core.c:723 read_lba+0x1b6/0x32c block/partitions/efi.c:247 find_valid_gpt.constprop.0+0x212/0x21ec block/partitions/efi.c:602 efi_partition+0xfe/0x9e0 block/partitions/efi.c:719 check_partition block/partitions/core.c:142 [inline] blk_add_partitions block/partitions/core.c:590 [inline] bdev_disk_changed+0x5a0/0x1180 block/partitions/core.c:694 blkdev_get_whole+0x168/0x25c block/bdev.c:764 bdev_open+0x288/0xcc4 block/bdev.c:973 blkdev_open+0x2ec/0x454 block/fops.c:697 do_dentry_open+0x418/0x1170 fs/open.c:949 vfs_open+0xba/0x3a8 fs/open.c:1081 do_open fs/namei.c:4671 [inline] path_openat+0x144e/0x2f28 fs/namei.c:4830 do_file_open+0x1ae/0x398 fs/namei.c:4859 do_sys_openat2+0xfe/0x1c0 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __riscv_sys_openat+0x122/0x1e4 fs/open.c:1383 syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x402/0x680 arch/riscv/kernel/traps.c:342 handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232 -> #5 (set->srcu){.+.+}-{0:0}: lock_sync+0xea/0x1cc kernel/locking/lockdep.c:5916 srcu_lock_sync include/linux/srcu.h:199 [inline] __synchronize_srcu+0xd4/0x24c kernel/rcu/srcutree.c:1505 synchronize_srcu_expedited kernel/rcu/srcutree.c:1545 [inline] synchronize_srcu+0x14c/0x3fc kernel/rcu/srcutree.c:1601 blk_mq_wait_quiesce_done block/blk-mq.c:284 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:281 [inline] blk_mq_quiesce_queue block/blk-mq.c:304 [inline] blk_mq_quiesce_queue+0x124/0x194 block/blk-mq.c:299 elevator_switch+0x16a/0x4e4 block/elevator.c:576 elevator_change+0x2f4/0x4ac block/elevator.c:681 elevator_set_default+0x280/0x370 block/elevator.c:754 blk_register_queue+0x3a8/0x50c block/blk-sysfs.c:946 __add_disk+0x69a/0xda4 block/genhd.c:528 add_disk_fwnode+0xe8/0x48c block/genhd.c:597 device_add_disk+0x28/0x38 block/genhd.c:627 add_disk include/linux/blkdev.h:785 [inline] nbd_dev_add+0x692/0xaec drivers/block/nbd.c:1984 nbd_init+0x3d4/0x3f8 drivers/block/nbd.c:2692 do_one_initcall+0x18c/0xcdc init/main.c:1382 do_initcall_level init/main.c:1444 [inline] do_initcalls init/main.c:1460 [inline] do_basic_setup init/main.c:1479 [inline] kernel_init_freeable+0x6ca/0x7b4 init/main.c:1692 kernel_init+0x28/0x240 init/main.c:1582 ret_from_fork_kernel+0x94/0xef8 arch/riscv/kernel/process.c:230 ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:363 -> #4 (&q->elevator_lock){+.+.}-{4:4}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x164/0x1890 kernel/locking/mutex.c:776 mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:828 elevator_change+0x192/0x4ac block/elevator.c:679 elevator_set_none+0xa8/0x120 block/elevator.c:769 blk_mq_elv_switch_none block/blk-mq.c:5110 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5155 [inline] blk_mq_update_nr_hw_queues+0x43a/0x13a0 block/blk-mq.c:5220 nbd_start_device+0x156/0xb74 drivers/block/nbd.c:1489 nbd_genl_connect+0xe74/0x1a4c drivers/block/nbd.c:2239 genl_family_rcv_msg_doit+0x1f6/0x2d8 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x4b2/0x73c net/netlink/genetlink.c:1209 netlink_rcv_skb+0x1e8/0x394 net/netlink/af_netlink.c:2550 genl_rcv+0x32/0x4c net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x50c/0x7d8 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x7e0/0xd64 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xca/0x160 net/socket.c:742 ____sys_sendmsg+0x636/0x794 net/socket.c:2592 ___sys_sendmsg+0x1a4/0x1e8 net/socket.c:2646 __sys_sendmsg+0x18e/0x234 net/socket.c:2678 __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __riscv_sys_sendmsg+0x70/0xa4 net/socket.c:2681 syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x402/0x680 arch/riscv/kernel/traps.c:342 handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232 -> #3 (&q->q_usage_counter(io)#20){++++}-{0:0}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 blk_alloc_queue+0x5b4/0x6f4 block/blk-core.c:461 blk_mq_alloc_queue+0x15e/0x250 block/blk-mq.c:4429 __blk_mq_alloc_disk+0x2a/0xd8 block/blk-mq.c:4476 nbd_dev_add+0x426/0xaec drivers/block/nbd.c:1954 nbd_init+0x3d4/0x3f8 drivers/block/nbd.c:2692 do_one_initcall+0x18c/0xcdc init/main.c:1382 do_initcall_level init/main.c:1444 [inline] do_initcalls init/main.c:1460 [inline] do_basic_setup init/main.c:1479 [inline] kernel_init_freeable+0x6ca/0x7b4 init/main.c:1692 kernel_init+0x28/0x240 init/main.c:1582 ret_from_fork_kernel+0x94/0xef8 arch/riscv/kernel/process.c:230 ret_from_fork_kernel_asm+0x16/0x18 arch/riscv/kernel/entry.S:363 -> #2 (fs_reclaim){+.+.}-{0:0}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 __fs_reclaim_acquire mm/page_alloc.c:4348 [inline] fs_reclaim_acquire+0xc6/0x100 mm/page_alloc.c:4362 might_alloc include/linux/sched/mm.h:317 [inline] slab_pre_alloc_hook mm/slub.c:4489 [inline] slab_alloc_node mm/slub.c:4843 [inline] kmem_cache_alloc_node_noprof+0x40/0x6e8 mm/slub.c:4918 __alloc_skb+0x17c/0x778 net/core/skbuff.c:702 alloc_skb_fclone include/linux/skbuff.h:1433 [inline] tcp_stream_alloc_skb+0x2e/0x4d8 net/ipv4/tcp.c:945 tcp_sendmsg_locked+0xe16/0x408c net/ipv4/tcp.c:1270 tcp_sendmsg+0x32/0x50 net/ipv4/tcp.c:1465 inet_sendmsg+0x9a/0xd8 net/ipv4/af_inet.c:865 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xca/0x160 net/socket.c:742 sock_write_iter+0x298/0x3e8 net/socket.c:1195 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x648/0xd08 fs/read_write.c:688 ksys_write+0x1f4/0x244 fs/read_write.c:740 __do_sys_write fs/read_write.c:751 [inline] __se_sys_write fs/read_write.c:748 [inline] __riscv_sys_write+0x6e/0xa0 fs/read_write.c:748 syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x402/0x680 arch/riscv/kernel/traps.c:342 handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232 -> #1 (sk_lock-AF_INET){+.+.}-{0:0}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 lock_sock_nested+0x38/0xf8 net/core/sock.c:3780 lock_sock include/net/sock.h:1709 [inline] inet_shutdown+0x68/0x3c0 net/ipv4/af_inet.c:919 kernel_sock_shutdown+0x58/0x7c net/socket.c:3679 nbd_mark_nsock_dead+0xaa/0x510 drivers/block/nbd.c:318 sock_shutdown+0x144/0x238 drivers/block/nbd.c:411 nbd_clear_sock drivers/block/nbd.c:1427 [inline] nbd_clear_sock_ioctl drivers/block/nbd.c:1575 [inline] __nbd_ioctl drivers/block/nbd.c:1603 [inline] nbd_ioctl+0x22c/0xbd4 drivers/block/nbd.c:1663 blkdev_ioctl+0x4cc/0x12e4 block/ioctl.c:804 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __riscv_sys_ioctl+0x17c/0x1e4 fs/ioctl.c:583 syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x402/0x680 arch/riscv/kernel/traps.c:342 handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232 -> #0 (&nsock->tx_lock){+.+.}-{4:4}: check_noncircular+0x138/0x14c 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+0xe9c/0x25ac kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 __mutex_lock_common kernel/locking/mutex.c:614 [inline] __mutex_lock+0x164/0x1890 kernel/locking/mutex.c:776 mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:828 nbd_handle_cmd drivers/block/nbd.c:1143 [inline] nbd_queue_rq+0x372/0xe44 drivers/block/nbd.c:1207 blk_mq_dispatch_rq_list+0x3cc/0x1ac0 block/blk-mq.c:2148 __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+0xe12/0x13cc block/blk-mq-sched.c:307 blk_mq_sched_dispatch_requests+0xb2/0x174 block/blk-mq-sched.c:329 blk_mq_run_hw_queue+0x274/0x6ec block/blk-mq.c:2386 blk_mq_dispatch_list+0x53e/0x1430 block/blk-mq.c:2949 blk_mq_flush_plug_list block/blk-mq.c:2997 [inline] blk_mq_flush_plug_list+0x114/0x55c block/blk-mq.c:2969 __blk_flush_plug+0x270/0x464 block/blk-core.c:1230 blk_finish_plug block/blk-core.c:1257 [inline] blk_finish_plug block/blk-core.c:1254 [inline] __submit_bio+0x42e/0x504 block/blk-core.c:649 __submit_bio_noacct_mq block/blk-core.c:722 [inline] submit_bio_noacct_nocheck+0x458/0xdf4 block/blk-core.c:753 submit_bio_noacct+0x6fe/0x2170 block/blk-core.c:884 submit_bio+0xb6/0x5b8 block/blk-core.c:926 blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline] submit_bh_wbc+0x428/0x5c0 fs/buffer.c:2821 submit_bh fs/buffer.c:2826 [inline] block_read_full_folio+0x396/0x788 fs/buffer.c:2444 blkdev_read_folio+0x26/0x30 block/fops.c:494 filemap_read_folio+0xc2/0x270 mm/filemap.c:2501 do_read_cache_folio+0x22e/0x518 mm/filemap.c:4101 read_cache_folio+0x4e/0x68 mm/filemap.c:4133 read_mapping_folio include/linux/pagemap.h:1028 [inline] read_part_sector+0xbc/0x408 block/partitions/core.c:723 read_lba+0x1b6/0x32c block/partitions/efi.c:247 find_valid_gpt.constprop.0+0x212/0x21ec block/partitions/efi.c:602 efi_partition+0xfe/0x9e0 block/partitions/efi.c:719 check_partition block/partitions/core.c:142 [inline] blk_add_partitions block/partitions/core.c:590 [inline] bdev_disk_changed+0x5a0/0x1180 block/partitions/core.c:694 blkdev_get_whole+0x168/0x25c block/bdev.c:764 bdev_open+0x288/0xcc4 block/bdev.c:973 blkdev_open+0x2ec/0x454 block/fops.c:697 do_dentry_open+0x418/0x1170 fs/open.c:949 vfs_open+0xba/0x3a8 fs/open.c:1081 do_open fs/namei.c:4671 [inline] path_openat+0x144e/0x2f28 fs/namei.c:4830 do_file_open+0x1ae/0x398 fs/namei.c:4859 do_sys_openat2+0xfe/0x1c0 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __riscv_sys_openat+0x122/0x1e4 fs/open.c:1383 syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112 do_trap_ecall_u+0x402/0x680 arch/riscv/kernel/traps.c:342 handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232 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 syz.1.1649/8329: #0: ffffaf801a976358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x3c4/0xcc4 block/bdev.c:961 #1: ffffaf8019e2b818 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x22c/0x6ec block/blk-mq.c:2386 #2: ffffaf802ff08180 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc4/0xe44 drivers/block/nbd.c:1199 stack backtrace: CPU: 0 UID: 0 PID: 8329 Comm: syz.1.1649 Tainted: G L syzkaller #0 PREEMPT Tainted: [L]=SOFTLOCKUP Hardware name: riscv-virtio,qemu (DT) Call Trace: [] dump_backtrace+0x2e/0x3c arch/riscv/kernel/stacktrace.c:149 [] show_stack+0x30/0x3c arch/riscv/kernel/stacktrace.c:155 [] __dump_stack lib/dump_stack.c:94 [inline] [] dump_stack_lvl+0x114/0x1ac lib/dump_stack.c:120 [] dump_stack+0x1c/0x28 lib/dump_stack.c:129 [] print_circular_bug+0x250/0x29c kernel/locking/lockdep.c:2043 [] check_noncircular+0x138/0x14c 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+0xe9c/0x25ac kernel/locking/lockdep.c:5237 [] lock_acquire kernel/locking/lockdep.c:5868 [inline] [] lock_acquire+0x24a/0x504 kernel/locking/lockdep.c:5825 [] __mutex_lock_common kernel/locking/mutex.c:614 [inline] [] __mutex_lock+0x164/0x1890 kernel/locking/mutex.c:776 [] mutex_lock_nested+0x14/0x1c kernel/locking/mutex.c:828 [] nbd_handle_cmd drivers/block/nbd.c:1143 [inline] [] nbd_queue_rq+0x372/0xe44 drivers/block/nbd.c:1207 [] blk_mq_dispatch_rq_list+0x3cc/0x1ac0 block/blk-mq.c:2148 [] __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+0xe12/0x13cc block/blk-mq-sched.c:307 [] blk_mq_sched_dispatch_requests+0xb2/0x174 block/blk-mq-sched.c:329 [] blk_mq_run_hw_queue+0x274/0x6ec block/blk-mq.c:2386 [] blk_mq_dispatch_list+0x53e/0x1430 block/blk-mq.c:2949 [] blk_mq_flush_plug_list block/blk-mq.c:2997 [inline] [] blk_mq_flush_plug_list+0x114/0x55c block/blk-mq.c:2969 [] __blk_flush_plug+0x270/0x464 block/blk-core.c:1230 [] blk_finish_plug block/blk-core.c:1257 [inline] [] blk_finish_plug block/blk-core.c:1254 [inline] [] __submit_bio+0x42e/0x504 block/blk-core.c:649 [] __submit_bio_noacct_mq block/blk-core.c:722 [inline] [] submit_bio_noacct_nocheck+0x458/0xdf4 block/blk-core.c:753 [] submit_bio_noacct+0x6fe/0x2170 block/blk-core.c:884 [] submit_bio+0xb6/0x5b8 block/blk-core.c:926 [] blk_crypto_submit_bio include/linux/blk-crypto.h:203 [inline] [] submit_bh_wbc+0x428/0x5c0 fs/buffer.c:2821 [] submit_bh fs/buffer.c:2826 [inline] [] block_read_full_folio+0x396/0x788 fs/buffer.c:2444 [] blkdev_read_folio+0x26/0x30 block/fops.c:494 [] filemap_read_folio+0xc2/0x270 mm/filemap.c:2501 [] do_read_cache_folio+0x22e/0x518 mm/filemap.c:4101 [] read_cache_folio+0x4e/0x68 mm/filemap.c:4133 [] read_mapping_folio include/linux/pagemap.h:1028 [inline] [] read_part_sector+0xbc/0x408 block/partitions/core.c:723 [] read_lba+0x1b6/0x32c block/partitions/efi.c:247 [] find_valid_gpt.constprop.0+0x212/0x21ec block/partitions/efi.c:602 [] efi_partition+0xfe/0x9e0 block/partitions/efi.c:719 [] check_partition block/partitions/core.c:142 [inline] [] blk_add_partitions block/partitions/core.c:590 [inline] [] bdev_disk_changed+0x5a0/0x1180 block/partitions/core.c:694 [] blkdev_get_whole+0x168/0x25c block/bdev.c:764 [] bdev_open+0x288/0xcc4 block/bdev.c:973 [] blkdev_open+0x2ec/0x454 block/fops.c:697 [] do_dentry_open+0x418/0x1170 fs/open.c:949 [] vfs_open+0xba/0x3a8 fs/open.c:1081 [] do_open fs/namei.c:4671 [inline] [] path_openat+0x144e/0x2f28 fs/namei.c:4830 [] do_file_open+0x1ae/0x398 fs/namei.c:4859 [] do_sys_openat2+0xfe/0x1c0 fs/open.c:1366 [] do_sys_open fs/open.c:1372 [inline] [] __do_sys_openat fs/open.c:1388 [inline] [] __se_sys_openat fs/open.c:1383 [inline] [] __riscv_sys_openat+0x122/0x1e4 fs/open.c:1383 [] syscall_handler+0x92/0x114 arch/riscv/include/asm/syscall.h:112 [] do_trap_ecall_u+0x402/0x680 arch/riscv/kernel/traps.c:342 [] handle_exception+0x15e/0x16a arch/riscv/kernel/entry.S:232 block nbd1: Dead connection, failed to find a fallback block nbd1: shutting down sockets I/O error, dev nbd1, sector 0 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 0, async page read I/O error, dev nbd1, sector 2 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 1, async page read I/O error, dev nbd1, sector 4 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 2, async page read I/O error, dev nbd1, sector 6 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 3, async page read I/O error, dev nbd1, sector 0 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 0, async page read I/O error, dev nbd1, sector 2 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 1, async page read I/O error, dev nbd1, sector 4 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 2, async page read I/O error, dev nbd1, sector 6 op 0x0:(READ) flags 0x800000 phys_seg 1 prio class 2 Buffer I/O error on dev nbd1, logical block 3, async page read nbd1: unable to read partition table block nbd1: Cannot use ioctl interface on a netlink controlled device. block nbd1: NBD_DISCONNECT block nbd1: Send disconnect failed -32 block nbd1: Send disconnect failed -32