[PATCH RFC v8 01/24] mm: Introduce kpkeys

[Linus Walleij]

On Tue, Jun 16, 2026 at 5:19 PM David Hildenbrand (Arm)
<david at kernel.org> wrote:

> Looking at this, and wondering about "why do we get registers involved in this
> API" I would probably have an interface like:
>
>         arch_kpkeys_enter_context()
>         arch_kpkeys_leave_context()
>
> Whereby you return a "struct kpkeys_state" or sth like that.

This is close to what I was looking for as well.

enter/leave makes the code look more like generic entry.

Passing some kind of state cookie around is inevitable in
this design and IIUC Kevin argued that it would be inefficient
(another level of abstraction) as opposed to just hammering
in the context we want, where we want it.

But I think the compiler will optimize that out by constant
propagation if the backing architecture implementation is
simple.

Yours,
Linus Walleij