There are also some users on 10+ year old 32-bit netbooks or business laptops, both x86 and Apple G4. The longest-lived 32-bit embedded systems with large memory (other than Arm) are probably NXP QorIQ P20xx/P40xx used in military VME bus systems, and low-end embedded systems based on Vortex86. I'm less worried about all of these because upstream kernel support for ppc32 and x86-32 is already bitrotting and they will likely get stuck on the last working kernel before the TI/Renesas/NXP Arm systems do.
Upstream kernel support for ppc32 is bitrotting, seriously ? What do you mean exactly ?
ppc32 is actively supported, with recent addition of support of hugepages, kasan, uaccess protection, VMAP stack, etc ...
Christophe
