Using busybox-1.31.1 loop mounting fails after mounting nine squashfs packages with: mount: can't setup loop device: No such file or directory /dev/loop0 -> /dev/loop8 exist After reversing the commit "mount,losetup: use /dev/loop-control is it exists" things now seem to work.
To clarify: Prior to loop mounting anything /dev/loop0 -> /dev/loop7 exist. After attempting to loop mount many squashfs packages, the error occurs when nine packages have been loop mounted and /dev/loop0 -> /dev/loop8 exist.