Re: [PATCH] irqchip/gic-v3-its: Add early memory allocation errata

From: Richter, Robert
Date: Fri Oct 05 2018 - 11:15:20 EST


On 05.10.18 16:13:48, Matthias Brugger wrote:
> On 05/10/2018 15:42, Marc Zyngier wrote:
> > On 05/10/18 13:33, Matthias Brugger wrote:

> >> With my distribution head on, I would prefer a solution that does not change
> >> FORCE_MAX_ZONEORDER. That's how I came to the idea providing a third solution to
> >> the same problem :)
> >
> > Why is that a problem? What impact does this have on your favourite distro?
> >
>
> The impact is on changing FORCE_MAX_ZONEORDER on an already released kernel will
> break Kernel ABI and with that all external modules. I know that's nothing
> upstream cares too much about, but the distros do :)

Wrt upstream, there is no way to do this change without patching the
kernel. Thus, it is impossible to run an unpatched 4k page size kernel
on ThunderX.

-Robert