Re: [PATCH v3] vm: optional 16K-page guest kernel builds

[Alyssa Ross <hi@alyssa.is>]

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On Sat, Aug 01, 2026 at 06:40:48PM +0000, colby@colbyt.com wrote:
> Seems fine, I don't have any special perspective on that.  Everything I have is 16k.

Alright, I'll throw that in next time we're doing a kernel rebuild. :)

> On Friday, July 31st, 2026 at 7:04 AM, Alyssa Ross <hi@alyssa.is> wrote:
>
> > colbyt <colby@colbyt.com> writes:
> >
>
> > > KVM hosts with a 16K stage-2 granule (Apple Silicon machines running
> > > upstream kernels, NVIDIA GB10) can only run guests whose kernel is built
> > > with ARM64_16K_PAGES. Add an optional kernelPageSize argument to the app
> > > and net VM kernel builds; the default is unchanged. A 16K-page guest
> > > Image built this way has booted to a full session under a 16K host here
> > > since June without issues on my side.
> > > ---
> > > v3/v2: no code change — drop a stray in-body From line that would have
> > > misattributed authorship when applied.
> > >
> > > Following up on the offer in my July 7 mail, as a standalone patch now
> > > that the nixpkgs update brings Linux 7.1. The config delta is five
> > > lines; the edit (an argument defaulting to today's behavior) is a
> > > proposal — happy to rework it if you'd rather structure it differently,
> > > e.g. hang it off a single shared helper instead of two arguments.
> >
>
> > My instinct is that we should just always use a 16K page kernel on
> > aarch64 hosts.  AIUI the main reason most Linux distributions don't is
> > to retain compatibility with binaries that may assume only 4K alignment
> > is needed, but on the Spectrum host we should never be running binaries
> > we didn't build ourselves.
> >


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