Why does CHKDSK report “free space marked as allocated in the MFT bitmap”?
Chkdsk sometimes optimizes the NTFS layout and later finds its own bugs (for instance when an index root attribute is moved from extent MFT record to the base one). This is not a problem with NTFS-3G. Workaround: No need, this is a CHKDSK bug. Status: The latest NTFS-3G optimized NTFS index metadata layout.