Re: arm64: MPAM2_EL2 and MPAMHCR_EL2 are left UNKNOWN under arm64.nompam

[Fuad Tabba]

On Wed, 2 Sept 2026 at 16:29, Bradley Morgan <brads@xxxxxxxxxxxxxx> wrote:
>
> On 2 September 2026 16:26:55 BST, Xi Ruoyao <xry111@xxxxxxxxxxx> wrote:
> >On Thu, 2026-08-27 at 09:41 +0100, Ben Horgan wrote:
> >> > not, could the caveat go the other way round: arm64.nompam is for
> >> > systems where firmware ignores MPAM, and should only be set on a
> >> > machine that does not boot without it?
> >>
> >> Yes, seems fine.
> >
> >Sorry for the late reply.  This is indeed the original purpose for
> >arm64.nompam, a dirty hack when we have no other ways to make the system
> >boot.  If you think it causes an inconsistent state I'd not complain
> >against adding a loud warning or something.
>
> Sorry to impede in the discussion, would you like me to submit a patch for
> that?

No, thanks. It's written already in the form Ben suggested. Will send it soon.

/fuad

>
> >
> >
>
> --- Thanks!
> https://lore.kernel.org/all/EE579805-42F2-4C58-B752-F28779EEB717@xxxxxxxxx/