Re: [PATCH 5.4 063/355] powerpc/kvm: Fix kvm_use_magic_page
From: Greg Kroah-Hartman
Date: Tue Nov 16 2021 - 08:57:25 EST
On Tue, Nov 16, 2021 at 02:54:10PM +0100, Andreas Gruenbacher wrote:
> On Tue, Nov 16, 2021 at 1:54 AM Sasha Levin <sashal@xxxxxxxxxx> wrote:
> > On Mon, Nov 15, 2021 at 06:47:41PM +0100, Andreas Gruenbacher wrote:
> > >Greg,
> > >
> > >On Mon, Nov 15, 2021 at 6:10 PM Greg Kroah-Hartman
> > ><gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > >> From: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
> > >>
> > >> commit 0c8eb2884a42d992c7726539328b7d3568f22143 upstream.
> > >>
> > >> When switching from __get_user to fault_in_pages_readable, commit
> > >> 9f9eae5ce717 broke kvm_use_magic_page: like __get_user,
> > >> fault_in_pages_readable returns 0 on success.
> > >
> > >I've not heard back from the maintainers about this patch so far, so
> > >it would probably be safer to leave it out of stable for now.
> > What do you mean exactly? It's upstream.
> Mathieu Malaterre broke this test in 2018 (commit 9f9eae5ce717) but
> that wasn't noticed until now (commit 0c8eb2884a42). This means that
> this fix probably isn't critical, so I shouldn't be backported.
Then why did you tag it to be explicitly backported to all stable
kernels newer than 4.18?
We are just doing what you asked to be done here...