====================================================== WARNING: possible circular locking dependency detected 6.13.0-rc2-syzkaller-00031-gf92f4749861b #0 Not tainted ------------------------------------------------------ syz.0.3229/18083 is trying to acquire lock: ffff8880280eb6c0 (&q->sysfs_lock){+.+.}-{4:4}, at: blk_register_queue+0x149/0x400 block/blk-sysfs.c:772 but task is already holding lock: ffff8880280eb750 (&q->sysfs_dir_lock){+.+.}-{4:4}, at: blk_register_queue+0x67/0x400 block/blk-sysfs.c:761 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #5 (&q->sysfs_dir_lock){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_mq_sysfs_unregister_hctxs+0xaa/0x300 block/blk-mq-sysfs.c:278 __blk_mq_update_nr_hw_queues block/blk-mq.c:5008 [inline] blk_mq_update_nr_hw_queues+0x6cc/0x1ae0 block/blk-mq.c:5063 nbd_start_device+0x16c/0xaa0 drivers/block/nbd.c:1413 nbd_start_device_ioctl drivers/block/nbd.c:1464 [inline] __nbd_ioctl drivers/block/nbd.c:1539 [inline] nbd_ioctl+0x5dc/0xf40 drivers/block/nbd.c:1579 blkdev_ioctl+0x57d/0x6a0 block/ioctl.c:693 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #4 (&q->q_usage_counter(io)#49){++++}-{0:0}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 bio_queue_enter block/blk.h:75 [inline] blk_mq_submit_bio+0x1536/0x2390 block/blk-mq.c:3092 __submit_bio+0x2c6/0x560 block/blk-core.c:629 __submit_bio_noacct_mq block/blk-core.c:710 [inline] submit_bio_noacct_nocheck+0x4d3/0xe30 block/blk-core.c:739 mpage_bio_submit_read fs/mpage.c:75 [inline] mpage_readahead+0x630/0x780 fs/mpage.c:377 read_pages+0x176/0x750 mm/readahead.c:160 page_cache_ra_unbounded+0x606/0x720 mm/readahead.c:295 do_page_cache_ra mm/readahead.c:325 [inline] force_page_cache_ra mm/readahead.c:354 [inline] page_cache_sync_ra+0x3c5/0xad0 mm/readahead.c:566 page_cache_sync_readahead include/linux/pagemap.h:1397 [inline] filemap_get_pages+0x605/0x2080 mm/filemap.c:2546 filemap_read+0x452/0xf50 mm/filemap.c:2646 blkdev_read_iter+0x2d8/0x430 block/fops.c:770 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x991/0xb70 fs/read_write.c:565 ksys_read+0x18f/0x2b0 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #3 (mapping.invalidate_lock#2){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 down_read+0xb1/0xa40 kernel/locking/rwsem.c:1524 filemap_invalidate_lock_shared include/linux/fs.h:873 [inline] page_cache_ra_unbounded+0x142/0x720 mm/readahead.c:226 do_sync_mmap_readahead+0x499/0x970 filemap_fault+0x8a9/0x1490 mm/filemap.c:3344 __do_fault+0x135/0x390 mm/memory.c:4907 do_read_fault mm/memory.c:5322 [inline] do_fault mm/memory.c:5456 [inline] do_pte_missing mm/memory.c:3979 [inline] handle_pte_fault+0x39eb/0x5ed0 mm/memory.c:5801 __handle_mm_fault mm/memory.c:5944 [inline] handle_mm_fault+0x1053/0x1ad0 mm/memory.c:6112 do_user_addr_fault arch/x86/mm/fault.c:1389 [inline] handle_page_fault arch/x86/mm/fault.c:1481 [inline] exc_page_fault+0x2b9/0x8b0 arch/x86/mm/fault.c:1539 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 rep_movs_alternative+0x30/0x70 arch/x86/lib/copy_user_64.S:50 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] _inline_copy_from_user include/linux/uaccess.h:178 [inline] _copy_from_user+0x7f/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] copy_msghdr_from_user+0xae/0x680 net/socket.c:2513 recvmsg_copy_msghdr net/socket.c:2769 [inline] ___sys_recvmsg net/socket.c:2841 [inline] do_recvmmsg+0x3bd/0xab0 net/socket.c:2940 __sys_recvmmsg net/socket.c:3014 [inline] __do_sys_recvmmsg net/socket.c:3037 [inline] __se_sys_recvmmsg net/socket.c:3030 [inline] __x64_sys_recvmmsg+0x199/0x250 net/socket.c:3030 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&mm->mmap_lock){++++}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __might_fault+0xc6/0x120 mm/memory.c:6751 _inline_copy_from_user include/linux/uaccess.h:162 [inline] _copy_from_user+0x2a/0xc0 lib/usercopy.c:18 copy_from_user include/linux/uaccess.h:212 [inline] __blk_trace_setup kernel/trace/blktrace.c:626 [inline] blk_trace_ioctl+0x1ad/0x9a0 kernel/trace/blktrace.c:740 blkdev_ioctl+0x40c/0x6a0 block/ioctl.c:682 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf5/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&q->debugfs_mutex){+.+.}-{4:4}: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_register_queue+0x15a/0x400 block/blk-sysfs.c:774 add_disk_fwnode+0x648/0xf80 block/genhd.c:493 add_disk include/linux/blkdev.h:755 [inline] brd_alloc+0x547/0x790 drivers/block/brd.c:401 brd_init+0x126/0x1b0 drivers/block/brd.c:481 do_one_initcall+0x248/0x870 init/main.c:1266 do_initcall_level+0x157/0x210 init/main.c:1328 do_initcalls+0x3f/0x80 init/main.c:1344 kernel_init_freeable+0x435/0x5d0 init/main.c:1577 kernel_init+0x1d/0x2b0 init/main.c:1466 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (&q->sysfs_lock){+.+.}-{4:4}: check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_register_queue+0x149/0x400 block/blk-sysfs.c:772 add_disk_fwnode+0x648/0xf80 block/genhd.c:493 add_disk include/linux/blkdev.h:755 [inline] loop_add+0x81d/0xaf0 drivers/block/loop.c:2077 blk_request_module+0x18d/0x1b0 block/genhd.c:809 blkdev_get_no_open+0x36/0xc0 block/bdev.c:784 bdev_file_open_by_dev+0x99/0x220 block/bdev.c:1005 setup_bdev_super+0x5d/0x5d0 fs/super.c:1554 mount_bdev+0x1c4/0x2d0 fs/super.c:1691 legacy_get_tree+0xee/0x190 fs/fs_context.c:662 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: &q->sysfs_lock --> &q->q_usage_counter(io)#49 --> &q->sysfs_dir_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&q->sysfs_dir_lock); lock(&q->q_usage_counter(io)#49); lock(&q->sysfs_dir_lock); lock(&q->sysfs_lock); *** DEADLOCK *** 3 locks held by syz.0.3229/18083: #0: ffff8880661cc0e0 (&type->s_umount_key#101/1){+.+.}-{4:4}, at: alloc_super+0x221/0x9d0 fs/super.c:344 #1: ffffffff8f04e148 (major_names_lock){+.+.}-{4:4}, at: blk_request_module+0x33/0x1b0 block/genhd.c:806 #2: ffff8880280eb750 (&q->sysfs_dir_lock){+.+.}-{4:4}, at: blk_register_queue+0x67/0x400 block/blk-sysfs.c:761 stack backtrace: CPU: 0 UID: 0 PID: 18083 Comm: syz.0.3229 Not tainted 6.13.0-rc2-syzkaller-00031-gf92f4749861b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2074 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2206 check_prev_add kernel/locking/lockdep.c:3161 [inline] check_prevs_add kernel/locking/lockdep.c:3280 [inline] validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3904 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5226 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5849 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0x1ac/0xee0 kernel/locking/mutex.c:735 blk_register_queue+0x149/0x400 block/blk-sysfs.c:772 add_disk_fwnode+0x648/0xf80 block/genhd.c:493 add_disk include/linux/blkdev.h:755 [inline] loop_add+0x81d/0xaf0 drivers/block/loop.c:2077 blk_request_module+0x18d/0x1b0 block/genhd.c:809 blkdev_get_no_open+0x36/0xc0 block/bdev.c:784 bdev_file_open_by_dev+0x99/0x220 block/bdev.c:1005 setup_bdev_super+0x5d/0x5d0 fs/super.c:1554 mount_bdev+0x1c4/0x2d0 fs/super.c:1691 legacy_get_tree+0xee/0x190 fs/fs_context.c:662 vfs_get_tree+0x90/0x2b0 fs/super.c:1814 do_new_mount+0x2be/0xb40 fs/namespace.c:3507 do_mount fs/namespace.c:3847 [inline] __do_sys_mount fs/namespace.c:4057 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4034 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f16e0b7ff19 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:00007f16e193d058 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f16e0d46160 RCX: 00007f16e0b7ff19 RDX: 0000000020000140 RSI: 0000000020000040 RDI: 0000000020000240 RBP: 00007f16e0bf3cc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f16e0d46160 R15: 00007ffd3424f1a8 block device autoloading is deprecated and will be removed. F2FS-fs (loop1): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop1): Can't find valid F2FS filesystem in 1th superblock F2FS-fs (loop1): Magic Mismatch, valid(0xf2f52010) - read(0x0) F2FS-fs (loop1): Can't find valid F2FS filesystem in 2th superblock