On Thu, Jun 12, 2025 at 05:36:35PM +0200, David Hildenbrand wrote:
> On 12.06.25 17:28, Lorenzo Stoakes wrote:
> > On Wed, Jun 11, 2025 at 02:06:52PM +0200, David Hildenbrand wrote:
> > > We setup the cache mode but ... don't forward the updated pgprot to
> > > insert_pfn_pud().
> > >
> > > Only a problem on x86-64 PAT when mapping PFNs using PUDs that
> > > require a special cachemode.
> > >
> > > Fix it by using the proper pgprot where the cachemode was setup.
> > >
> > > Identified by code inspection.
> > >
> > > Fixes: 7b806d229ef1 ("mm: remove vmf_insert_pfn_xxx_prot() for huge
> > > page-table entries")
Ha! I don't even remember doing that patch... hm did I introduce this -ignoring
cache- thing? Sorry! :P
> > > Cc: <sta...@vger.kernel.org>
> > > Signed-off-by: David Hildenbrand <da...@redhat.com>
> >
> > Nice catch!
> >
> > Reviewed-by: Lorenzo Stoakes <lorenzo.stoa...@oracle.com>
>
> Thanks! What's your opinion on stable? Really hard to judge the impact ...
I think it makes sense? This is currently incorrect so let's do the right thing
and backport.
I think as per Dan it's probably difficult to picture this causing a problem,
but on principle I think this is correct, and I don't see any harm in
backporting?
>
> --
> Cheers,
>
> David / dhildenb
>
