Re: [PATCH 00/31 v2] PTI support for x86_32

[Linus Torvalds]

On Fri, Feb 9, 2018 at 1:09 PM, Pavel Machek <pavel@xxxxxx> wrote:
>
> Hardware supports PCID even on 32-bit kernels, no?

We're not adding support for it even if it were possible. No way.

Christ, even if you want to run 32-bit user code, you'd better run a
64-bit kernel. Backporting the PCID bits to something that no actual
real developer will ever use is crazy and unacceptable.

             Linus