[TECH TOPIC] Reaching consensus on CONFIG_HIGHMEM phaseout

[Linus Walleij]

On Wed, Sep 10, 2025 at 3:46 AM Matthew Wilcox <willy at infradead.org> wrote:

> I don't mind that the feature remains ... unless it causes us trouble.
> Which it currently does.  Perhaps we could start by removing HIGHPTE?
> There was a certain amount of complexity introduced into the page fault
> path when support for that was introduced.  x86 removed support for it,
> so it's just ARM left before we can remove the complexity again.

I sent an RFC patch so we can see what Russell has to say about this,
it is currently only enabled by default on the VT8500 machine.

Yours,
Linus Walleij