4.4 btrfs-convert operation results in a file system that cannot be mounted

The btrfs-convert tool can be used to convert an ext4 file system to btrfs. However, if the tool attempts to convert a file system that has not been created with a sector block size that matches the system default page size (which is set to 64 KB for the aarch64 platform) the resulting file system cannot be mounted. This issue can occur if the original ext4 file system is not created by using the -b 65536 option to specify a 64 KB block size.

(Bug ID 28200561)