====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc2-syzkaller-00041-g4dc1d1bec898 #0 Not tainted ------------------------------------------------------ syz.0.6071/27731 is trying to acquire lock: ffff888144bd6110 (set->srcu){.+.+}-{0:0}, at: srcu_lock_sync include/linux/srcu.h:176 [inline] ffff888144bd6110 (set->srcu){.+.+}-{0:0}, at: __synchronize_srcu+0x99/0x2a0 kernel/rcu/srcutree.c:1418 but task is already holding lock: ffff888025f5cf58 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4937 [inline] ffff888025f5cf58 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5018 [inline] ffff888025f5cf58 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x4a7/0x1360 block/blk-mq.c:5070 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #6 (&q->sysfs_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 blk_mq_elv_switch_none block/blk-mq.c:4937 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5018 [inline] blk_mq_update_nr_hw_queues+0x4a7/0x1360 block/blk-mq.c:5070 nbd_start_device+0x172/0xcd0 drivers/block/nbd.c:1476 nbd_start_device_ioctl drivers/block/nbd.c:1527 [inline] __nbd_ioctl drivers/block/nbd.c:1602 [inline] nbd_ioctl+0x21a/0xd60 drivers/block/nbd.c:1642 blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #5 (&q->q_usage_counter(io)#50){++++}-{0:0}: bio_queue_enter block/blk.h:77 [inline] blk_mq_submit_bio+0x20db/0x25f0 block/blk-mq.c:3091 __submit_bio+0x3d1/0x690 block/blk-core.c:628 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 mpage_bio_submit_read fs/mpage.c:75 [inline] mpage_readahead+0x41d/0x590 fs/mpage.c:377 read_pages+0x1a7/0xc60 mm/readahead.c:161 page_cache_ra_unbounded+0x426/0x7d0 mm/readahead.c:298 do_page_cache_ra mm/readahead.c:328 [inline] force_page_cache_ra+0x24b/0x340 mm/readahead.c:357 page_cache_sync_ra+0x158/0xa30 mm/readahead.c:585 filemap_get_pages+0xb62/0x1c30 mm/filemap.c:2580 filemap_read+0x3c5/0xe70 mm/filemap.c:2691 blkdev_read_iter+0x187/0x4b0 block/fops.c:796 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x886/0xbf0 fs/read_write.c:565 ksys_read+0x12b/0x250 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (mapping.invalidate_lock#2){++++}-{4:4}: down_read+0x9a/0x330 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:932 [inline] page_cache_ra_unbounded+0x173/0x7d0 mm/readahead.c:229 do_page_cache_ra mm/readahead.c:328 [inline] page_cache_ra_order+0x9cd/0xd00 mm/readahead.c:533 do_sync_mmap_readahead mm/filemap.c:3260 [inline] filemap_fault+0x16d2/0x2ca0 mm/filemap.c:3447 __do_fault+0x10a/0x490 mm/memory.c:4977 do_read_fault mm/memory.c:5392 [inline] do_fault mm/memory.c:5526 [inline] do_pte_missing+0xecf/0x3e10 mm/memory.c:4047 handle_pte_fault mm/memory.c:5889 [inline] __handle_mm_fault+0x1166/0x2c60 mm/memory.c:6032 handle_mm_fault+0x3fa/0xaa0 mm/memory.c:6201 do_user_addr_fault+0x7a3/0x13f0 arch/x86/mm/fault.c:1388 handle_page_fault arch/x86/mm/fault.c:1480 [inline] exc_page_fault+0x5c/0xc0 arch/x86/mm/fault.c:1538 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 rep_movs_alternative+0x4a/0x70 arch/x86/lib/copy_user_64.S:65 copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline] raw_copy_from_user arch/x86/include/asm/uaccess_64.h:141 [inline] copy_from_user_iter lib/iov_iter.c:55 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:300 [inline] iterate_and_advance include/linux/iov_iter.h:328 [inline] __copy_from_iter lib/iov_iter.c:249 [inline] _copy_from_iter+0x385/0x1560 lib/iov_iter.c:260 copy_from_iter include/linux/uio.h:228 [inline] copy_from_iter_full include/linux/uio.h:245 [inline] do_copy_data_nocache net/mptcp/protocol.c:1786 [inline] mptcp_sendmsg+0x1010/0x1f50 net/mptcp/protocol.c:1893 inet_sendmsg+0x119/0x140 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:733 [inline] __sys_sendto+0x42a/0x4f0 net/socket.c:2187 __do_sys_sendto net/socket.c:2194 [inline] __se_sys_sendto net/socket.c:2190 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2190 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (sk_lock-AF_INET){+.+.}-{0:0}: lock_sock_nested+0x3a/0xf0 net/core/sock.c:3645 lock_sock include/net/sock.h:1624 [inline] inet_shutdown+0x67/0x440 net/ipv4/af_inet.c:905 nbd_mark_nsock_dead+0xae/0x5d0 drivers/block/nbd.c:318 sock_shutdown+0x17c/0x280 drivers/block/nbd.c:411 nbd_start_device_ioctl drivers/block/nbd.c:1537 [inline] __nbd_ioctl drivers/block/nbd.c:1602 [inline] nbd_ioctl+0xb21/0xd60 drivers/block/nbd.c:1642 blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&nsock->tx_lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 nbd_handle_cmd drivers/block/nbd.c:1140 [inline] nbd_queue_rq+0x424/0x1220 drivers/block/nbd.c:1204 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x547/0x690 block/blk-core.c:642 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 submit_bh fs/buffer.c:2819 [inline] __bread_slow fs/buffer.c:1264 [inline] __bread_gfp+0x189/0x340 fs/buffer.c:1488 sb_bread include/linux/buffer_head.h:346 [inline] udf_check_vsd fs/udf/super.c:772 [inline] udf_load_vrs+0x8cb/0x1050 fs/udf/super.c:2006 udf_fill_super+0x79b/0x1e00 fs/udf/super.c:2192 get_tree_bdev_flags+0x38b/0x620 fs/super.c:1636 vfs_get_tree+0x8b/0x340 fs/super.c:1814 do_new_mount fs/namespace.c:3560 [inline] path_mount+0x14e6/0x1f10 fs/namespace.c:3887 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __x64_sys_mount+0x28f/0x310 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&cmd->lock){+.+.}-{4:4}: __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730 nbd_queue_rq+0xbe/0x1220 drivers/block/nbd.c:1196 blk_mq_dispatch_rq_list+0x443/0x1dc0 block/blk-mq.c:2120 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:170 [inline] blk_mq_do_dispatch_sched block/blk-mq-sched.c:184 [inline] __blk_mq_sched_dispatch_requests+0xcdf/0x1620 block/blk-mq-sched.c:309 blk_mq_sched_dispatch_requests+0xd8/0x1b0 block/blk-mq-sched.c:331 blk_mq_run_hw_queue+0x239/0x670 block/blk-mq.c:2354 blk_mq_dispatch_plug_list block/blk-mq.c:2866 [inline] blk_mq_flush_plug_list+0x673/0x1c60 block/blk-mq.c:2917 __blk_flush_plug+0x2c5/0x4b0 block/blk-core.c:1213 blk_finish_plug block/blk-core.c:1240 [inline] blk_finish_plug block/blk-core.c:1237 [inline] __submit_bio+0x547/0x690 block/blk-core.c:642 __submit_bio_noacct_mq block/blk-core.c:715 [inline] submit_bio_noacct_nocheck+0x698/0xd70 block/blk-core.c:744 submit_bio_noacct+0x50d/0x1ec0 block/blk-core.c:867 submit_bh fs/buffer.c:2819 [inline] __bread_slow fs/buffer.c:1264 [inline] __bread_gfp+0x189/0x340 fs/buffer.c:1488 sb_bread include/linux/buffer_head.h:346 [inline] udf_check_vsd fs/udf/super.c:772 [inline] udf_load_vrs+0x8cb/0x1050 fs/udf/super.c:2006 udf_fill_super+0x79b/0x1e00 fs/udf/super.c:2192 get_tree_bdev_flags+0x38b/0x620 fs/super.c:1636 vfs_get_tree+0x8b/0x340 fs/super.c:1814 do_new_mount fs/namespace.c:3560 [inline] path_mount+0x14e6/0x1f10 fs/namespace.c:3887 do_mount fs/namespace.c:3900 [inline] __do_sys_mount fs/namespace.c:4111 [inline] __se_sys_mount fs/namespace.c:4088 [inline] __x64_sys_mount+0x28f/0x310 fs/namespace.c:4088 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (set->srcu){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_sync+0xf5/0x190 kernel/locking/lockdep.c:5899 srcu_lock_sync include/linux/srcu.h:176 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:293 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_quiesce_queue block/blk-mq.c:313 [inline] blk_mq_quiesce_queue+0x149/0x1b0 block/blk-mq.c:308 elevator_disable+0xe9/0x570 block/elevator.c:661 blk_mq_elv_switch_none block/blk-mq.c:4951 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5018 [inline] blk_mq_update_nr_hw_queues+0x41c/0x1360 block/blk-mq.c:5070 nbd_start_device+0x172/0xcd0 drivers/block/nbd.c:1476 nbd_start_device_ioctl drivers/block/nbd.c:1527 [inline] __nbd_ioctl drivers/block/nbd.c:1602 [inline] nbd_ioctl+0x21a/0xd60 drivers/block/nbd.c:1642 blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: set->srcu --> &q->q_usage_counter(io)#50 --> &q->sysfs_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->sysfs_lock); lock(&q->q_usage_counter(io)#50); lock(&q->sysfs_lock); sync(set->srcu); *** DEADLOCK *** 5 locks held by syz.0.6071/27731: #0: ffff888026014198 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x151/0xd60 drivers/block/nbd.c:1635 #1: ffff8880260140d8 (&set->tag_list_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x8f/0x1360 block/blk-mq.c:5069 #2: ffff888025f5ca28 (&q->q_usage_counter(io)#49){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave block/blk-mq.c:215 [inline] #2: ffff888025f5ca28 (&q->q_usage_counter(io)#49){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5010 [inline] #2: ffff888025f5ca28 (&q->q_usage_counter(io)#49){+.+.}-{0:0}, at: blk_mq_update_nr_hw_queues+0x264/0x1360 block/blk-mq.c:5070 #3: ffff888025f5ca60 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave block/blk-mq.c:215 [inline] #3: ffff888025f5ca60 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5010 [inline] #3: ffff888025f5ca60 (&q->q_usage_counter(queue)#33){+.+.}-{0:0}, at: blk_mq_update_nr_hw_queues+0x264/0x1360 block/blk-mq.c:5070 #4: ffff888025f5cf58 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_elv_switch_none block/blk-mq.c:4937 [inline] #4: ffff888025f5cf58 (&q->sysfs_lock){+.+.}-{4:4}, at: __blk_mq_update_nr_hw_queues block/blk-mq.c:5018 [inline] #4: ffff888025f5cf58 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_mq_update_nr_hw_queues+0x4a7/0x1360 block/blk-mq.c:5070 stack backtrace: CPU: 0 UID: 0 PID: 27731 Comm: syz.0.6071 Not tainted 6.14.0-rc2-syzkaller-00041-g4dc1d1bec898 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228 lock_sync+0xf5/0x190 kernel/locking/lockdep.c:5899 srcu_lock_sync include/linux/srcu.h:176 [inline] __synchronize_srcu+0xa9/0x2a0 kernel/rcu/srcutree.c:1418 blk_mq_wait_quiesce_done block/blk-mq.c:293 [inline] blk_mq_wait_quiesce_done block/blk-mq.c:290 [inline] blk_mq_quiesce_queue block/blk-mq.c:313 [inline] blk_mq_quiesce_queue+0x149/0x1b0 block/blk-mq.c:308 elevator_disable+0xe9/0x570 block/elevator.c:661 blk_mq_elv_switch_none block/blk-mq.c:4951 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5018 [inline] blk_mq_update_nr_hw_queues+0x41c/0x1360 block/blk-mq.c:5070 nbd_start_device+0x172/0xcd0 drivers/block/nbd.c:1476 nbd_start_device_ioctl drivers/block/nbd.c:1527 [inline] __nbd_ioctl drivers/block/nbd.c:1602 [inline] nbd_ioctl+0x21a/0xd60 drivers/block/nbd.c:1642 blkdev_ioctl+0x276/0x6d0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __x64_sys_ioctl+0x190/0x200 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0fb118cde9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0fb1f5f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f0fb13a5fa0 RCX: 00007f0fb118cde9 RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004 RBP: 00007f0fb120e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f0fb13a5fa0 R15: 00007fff00ff8ae8 block nbd0: shutting down sockets