__process6_stack_size__ is not defined in u2f.ld

[anvol]

Following error received while linking

u2f-token/u2f/pbt.c:114: undefined reference to '__process6_stack_size__'

I guess, we need to reserve some space on stack in u2f.ld

board.h -> board-blue-pill.h

[gl-sergei]

You need to put some effort to make it run on blue pill. Since this board doesn't have user buttons, you probably want to revert to commit e12df0f.

[anvol]

Yes, thanks!
FYI - device works as expected even using reset btn as user action (macOS, Chrome).
I think there might be easier to reroute/resolder reset btn to different pin and use it as user btn.

And thanks again for u2f project! Just what I was looking for)

[gl-sergei]

True. It works because device indicates user presence during the first 10 seconds after startup. I've missed that bit.