Pitting on frame rails

[glazuna]

Hi fellow Luger owners, I acquired a pristine DWM piece probably from 1930s (3 digit serial), but rails on the frame are pitted quite deeply on some places, however it doesn't seem to affect the operation and it runs smoothly. Should I be concerned and does this require a repair in order to not get worse soon?

The slide doesn't seem that pitted, just at the ends.