Re: [RFC PATCH 1/3] x86/mm: fix LAM cr3 mask inconsistency during context switch

[Yosry Ahmed <yosryahmed@google.com>]

> > Or we can avoid returning a value from the helper and avoid passing an
> > mm. The callers would be more verbose, they'll have to call
> > mm_lam_cr3_mask() and mm_untag_mask() and pass the results into the
> > helper (set_tlbstate_lam_mode() or update_cpu_tlbstate_lam()). Another
> > advantage of this is that we can move the READ_ONCE to
> > switch_mm_irqs_off() and keep the comment here.
>
>
> One thing I don't like about set_tlbstate_lam_mode() is that it's not
> obvious that it's writing to "cpu_tlbstate" and its right smack in the
> middle of a bunch of other writers to the same thing.
>
> But I'm also not sure that open-coding it at its three call sites makes
> things better overall.
>
> I honestly don't have any brilliant suggestions.

Let me ponder this a little bit and try to come up with something, I
think a max of renaming and open-coding could make an improvement.

Thanks!