Re: [PATCH 2/2] xen: don't use page->lru for ZONE_DEVICE memory

[Jürgen Groß]

On 07.12.20 21:48, Jason Andryuk wrote:
> On Mon, Dec 7, 2020 at 8:30 AM Juergen Gross <jgross@xxxxxxxx> wrote:
> > Commit 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated
> > memory") introduced usage of ZONE_DEVICE memory for foreign memory
> > mappings.
> >
> > Unfortunately this collides with using page->lru for Xen backend
> > private page caches.
> >
> > Fix that by using page->zone_device_data instead.
> >
> > Fixes: 9e2369c06c8a18 ("xen: add helpers to allocate unpopulated memory")
> > Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
>
> Would it make sense to add BUG_ON(is_zone_device_page(page)) and the
> opposite as appropriate to cache_enq?

No, I don't think so. At least in the CONFIG_ZONE_DEVICE case the
initial list in a PV dom0 is populated from extra memory (basically
the same, but not marked as zone device memory explicitly).

Juergen

Attachment: OpenPGP_0xB0DE9DD628BF132F.asc
Description: application/pgp-keys

Attachment: OpenPGP_signature
Description: OpenPGP digital signature