Re: [RFC PATCH 00/22] riscv: s64ilp32: Running 32-bit Linux kernel on 64-bit supervisor mode

[Paul Walmsley]

On Thu, 18 May 2023, Arnd Bergmann wrote:

> We have had long discussions about supporting ilp32 userspace on
> arm64, and I think almost everyone is glad we never merged it into
> the mainline kernel, so we don't have to worry about supporting it
> in the future. The cost of supporting an extra user space ABI
> is huge, and I'm sure you don't want to go there. The other two
> cited examples (mips-n32 and x86-x32) are pretty much unused now
> as well, but still have a maintenance burden until they can finally
> get removed.

There probably hasn't been much pressure to support Aarch64 ILP32 since 
ARM still has hardware support for Aarch32.  Will be interesting to see if 
that's still the case after ARM drops Aarch32 support for future designs.


- Paul