Re: [kvm-unit-tests PATCH] arm64: Default to 4K translation granule

[Alexandru Elisei <alexandru.elisei@arm.com>]

Hi,

On Thu, May 02, 2024 at 09:58:39AM +0200, Thomas Huth wrote:
> On 02/05/2024 09.41, Oliver Upton wrote:
> > Some arm64 implementations in the wild, like the Apple parts, do not
> > support the 64K translation granule. This can be a bit annoying when
> > running with the defaults on such hardware, as every test fails
> > before getting the MMU turned on.
> > 
> > Switch the default page size to 4K with the intention of having the
> > default setting be the most widely applicable one.
> 
> What about using "getconf PAGESIZE" to get the page size of the host
> environment? Would that work, too?

That would definitely make the tests run,  but I'm worried about
reproducibility. If you want to re-run a failed test on a different
machine, this introduces a new variable, the host's page size, which might
be different between the machines. Or, if you want to look it another way,
another configuration knob that the user has to be aware of and control.

Unless there's a system out there that doesn't support 4K pages, I'm in
favour of having 4K the default.

Thanks,
Alex

> 
>  Thomas
> 
>