====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc1-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.2/5444 is trying to acquire lock: ffff88811f1260e0 (&type->s_umount_key#25){++++}-{3:3}, at: __super_lock fs/super.c:58 [inline] ffff88811f1260e0 (&type->s_umount_key#25){++++}-{3:3}, at: super_lock+0xe5/0x160 fs/super.c:117 but task is already holding lock: ffff8881084d71c8 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] ffff8881084d71c8 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x553/0xaf0 block/ioctl.c:502 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&bdev->bd_holder_lock){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0xab/0xa10 kernel/locking/mutex.c:747 bdev_mark_dead+0x1e/0xa0 block/bdev.c:961 disk_force_media_change+0x2b/0x40 block/disk-events.c:303 __loop_clr_fd+0x112/0x250 drivers/block/loop.c:1174 blkdev_put+0xfe/0x1c0 block/bdev.c:898 blkdev_release+0x26/0x30 block/fops.c:604 __fput+0xf0/0x290 fs/file_table.c:384 __do_sys_close fs/open.c:1572 [inline] __se_sys_close fs/open.c:1557 [inline] __x64_sys_close+0x38/0x80 fs/open.c:1557 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&disk->open_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0xab/0xa10 kernel/locking/mutex.c:747 blkdev_get_by_dev.part.0+0xfb/0x330 block/bdev.c:786 journal_init_dev fs/reiserfs/journal.c:2626 [inline] journal_init+0x2b8/0x17f0 fs/reiserfs/journal.c:2786 reiserfs_fill_super+0x4b7/0xdd0 fs/reiserfs/super.c:2022 mount_bdev+0xfd/0x150 fs/super.c:1629 legacy_get_tree+0x2c/0x50 fs/fs_context.c:638 vfs_get_tree+0x1d/0xa0 fs/super.c:1750 do_new_mount fs/namespace.c:3335 [inline] path_mount+0x48a/0xb80 fs/namespace.c:3662 do_mount fs/namespace.c:3675 [inline] __do_sys_mount fs/namespace.c:3884 [inline] __se_sys_mount fs/namespace.c:3861 [inline] __x64_sys_mount+0x111/0x150 fs/namespace.c:3861 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&type->s_umount_key#25){++++}-{3:3}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x12e6/0x1d00 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0xcd/0x2d0 kernel/locking/lockdep.c:5718 down_read+0x2c/0xf0 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0xe5/0x160 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x25/0x70 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x575/0xaf0 block/ioctl.c:502 blkdev_ioctl+0x117/0x2a0 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x8b/0xc0 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &type->s_umount_key#25 --> &disk->open_mutex --> &bdev->bd_holder_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bdev->bd_holder_lock); lock(&disk->open_mutex); lock(&bdev->bd_holder_lock); rlock(&type->s_umount_key#25); *** DEADLOCK *** 1 lock held by syz-executor.2/5444: #0: ffff8881084d71c8 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_flushbuf block/ioctl.c:370 [inline] #0: ffff8881084d71c8 (&bdev->bd_holder_lock){+.+.}-{3:3}, at: blkdev_common_ioctl+0x553/0xaf0 block/ioctl.c:502 stack backtrace: CPU: 0 PID: 5444 Comm: syz-executor.2 Not tainted 6.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x5c/0xb0 lib/dump_stack.c:106 check_noncircular+0x116/0x130 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x12e6/0x1d00 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0xcd/0x2d0 kernel/locking/lockdep.c:5718 down_read+0x2c/0xf0 kernel/locking/rwsem.c:1520 __super_lock fs/super.c:58 [inline] super_lock+0xe5/0x160 fs/super.c:117 super_lock_shared fs/super.c:146 [inline] super_lock_shared_active fs/super.c:1431 [inline] fs_bdev_sync+0x25/0x70 fs/super.c:1466 blkdev_flushbuf block/ioctl.c:372 [inline] blkdev_common_ioctl+0x575/0xaf0 block/ioctl.c:502 blkdev_ioctl+0x117/0x2a0 block/ioctl.c:624 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x8b/0xc0 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f86b787cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f86b85620c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f86b799bf80 RCX: 00007f86b787cae9 RDX: 0000000000000003 RSI: 0000000000001261 RDI: 0000000000000003 RBP: 00007f86b78c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000016 R14: 00007f86b799bf80 R15: 00007fff9a9c6ca8