Re: [TECH TOPIC] Reaching consensus on CONFIG_HIGHMEM phaseout

On Wed, Sep 10, 2025 at 3:46 AM Matthew Wilcox [off-list ref] 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