> But the main win as I see it is that that's basically complete support
> for 32-bit arches. People do ask about arm32 support:
> https://groups.google.com/d/msg/kasan-dev/Sk6BsSPMRRc/Gqh4oD_wAAAJ
> https://groups.google.com/d/msg/kasan-dev/B22vOFp-QWg/EVJPbrsgAgAJ
> and probably mips32 is relevant as well.

I don't see how above is relevant for 32-bit arches. Current design
is perfectly fine for 32-bit arches. I did some POC arm32 port couple years
ago - https://github.com/aryabinin/linux/commits/kasan/arm_v0_1
It has some ugly hacks and non-critical bugs. AFAIR it also super-slow because I (mistakenly)
made shadow memory uncached. But otherwise it works.