Re: [PATCH 2/2] selftests: KVM: Add page splitting test

From: Ricardo Koller
Date: Tue Jan 24 2023 - 10:41:14 EST


On Fri, Jan 20, 2023 at 12:04:04PM -0800, Ben Gardon wrote:
> On Fri, Jan 20, 2023 at 6:34 AM Ricardo Koller <ricarkol@xxxxxxxxxx> wrote:
> >
> ...
> > > > > > +
> > > > > > + run_test(&p);
> > > > >
> > > > > Use for_each_guest_mode() to run against all supported guest modes.
> > > >
> > > > I'm not sure that would actually improve coverage. None of the page
> > > > splitting behavior depends on the mode AFAICT.
> > >
> > > You need to use for_each_guest_mode() for the ARM case. The issue is
> > > that whatever mode (guest page size and VA size) you pick might not be
> > > supported by the host. So, you first to explore what's available (via
> > > for_each_guest_mode()).
> >
> > Actually, that's fixed by using the default mode, which picks the
> > first available
> > mode. I would prefer to use for_each_guest_mode() though, who knows and
> > something fails with some specific guest page size for some reason.
>
> Okay, will do. I wasn't sure if we did eager page splitting on ARM, so
> I was only planning on making this test for x86_64 initially, hence it

Thanks Ben, just saw that V2 has the for_each_guest_mode() change.
> being in that directory. If ARM rolls with the same behavior, then
> I'll add the for_each_mode bit and move the test up a directory.

No wories, I can take care of that as part of my ARM changes, maybe even
as part of the eager splitting series.

> >
> > >
> > > Thanks,
> > > Ricardo
> > >
> > > >
> > > > >
> > > > > > +
> > > > > > + return 0;
> > > > > > +}
> > > > > > --
> > > > > > 2.39.1.405.gd4c25cc71f-goog
> > > > > >