loop3: detected capacity change from 42864 to 0
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BUG: KCSAN: data-race in __blkdev_put / __blkdev_put

read-write to 0xffff888101e1d6a0 of 4 bytes by task 4895 on cpu 0:
 __blkdev_put+0x10f/0x450 fs/block_dev.c:1561
 blkdev_put+0x212/0x290 fs/block_dev.c:1624
 blkdev_close+0x47/0x50 fs/block_dev.c:1632
 __fput+0x24b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0x8e/0x110 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x16b/0x1a0 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888101e1d6a0 of 4 bytes by task 14872 on cpu 1:
 __blkdev_put+0x5a/0x450 fs/block_dev.c:1554
 blkdev_put+0x212/0x290 fs/block_dev.c:1624
 btrfs_scan_one_device+0x2ab/0x2f0 fs/btrfs/volumes.c:1381
 btrfs_mount_root+0x348/0x810 fs/btrfs/super.c:1686
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:592
 vfs_get_tree+0x4a/0x190 fs/super.c:1496
 fc_mount fs/namespace.c:978 [inline]
 vfs_kern_mount+0xc6/0x130 fs/namespace.c:1008
 btrfs_mount+0x278/0x740 fs/btrfs/super.c:1784
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:592
 vfs_get_tree+0x4a/0x190 fs/super.c:1496
 do_new_mount fs/namespace.c:2878 [inline]
 path_mount+0x119d/0x1c10 fs/namespace.c:3208
 do_mount fs/namespace.c:3221 [inline]
 __do_sys_mount fs/namespace.c:3429 [inline]
 __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3406
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3406
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 14872 Comm: syz-executor.3 Not tainted 5.11.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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