I was able to get the New 3DS memory to work just fine in 3DS Linux by editing the dtb file.
You'll need the dtc (Device Tree Compiler) package.
Code:
fdtdump nintendo3ds_ctr.dtb > nintendo3ds_ctr.dts
Open the file and edit the line after:
and change the second value from 0x08000000 to 0x10000000.
Code:
dtc -O dtb nintendo3ds_ctr.dts >nintendo3ds_ctr.dtb
(chat's capital letter 'O'.)
Overwrite the file in the linux directory in your SD card and boot up and you should have 247MB total memory. Tested by filling up tmpfs and it seems to work just fine.
In case anyone thinks you can just change the size and get more free RAM, that is not the case and this will not work on the Old 3DS. The New 3DS just has more RAM that extends past the RAM region within the Old 3DS, but it's still only 256MB.
At that point, this could be legitimately useful if this had a keyboard like the one from the original DSLinux and networking.
EDIT: I have a touch screen based virtual keyboard mostly working. I'll put in a pull request once I clear up a few more quirks I'm running in to with it.
Also, CTRL+ALT+SHIFT+SYSRQ+B seems to crash it.