Use a single stack

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1

Hello,

I’m currently working on an ARM Cortex M4 where RIOT uses both MSP and PSP stacks, I’m looking to run RIOT using only one stack (MSP or PSP), is there a setting for this?

Thanks to you

2

Nope, RIOT’s use of the two different stack pointers on Cortex-M is hard-coded in several places and not trivial to change. The scheduling code depends on it.

It might be possible to allow using only one of the stack pointers, but I think it would basically require duplicating the scheduling code. And the one-stack-pointer version would probably get a bit messy. There’s a reason for dual SPs, some things are convenient to implement.

What’s the use case? Running RIOT from non-privileged mode?

3

Thank you for your answer Kasper, you got it right, it’s for running RIOT in non-privileged mode, is there any other project working on that ?

Thank you