Some flash space should be allocated for custom usage.

[dty717]

In memmap_default.ld(line 26),

    FLASH(rx) : ORIGIN = 0x10000000, LENGTH = 2048k

It could be better with some space reserved, like

    FLASH(rx) : ORIGIN = 0x10000000, LENGTH = 2040k /*8k for custom storage*/

[lurch]

IMVHO if you want that, that's something that you should add to your own custom linker script?