Re: [External] Re: [PATCH v2] mm/page_isolation: do not isolate the max order page

[Muchun Song]

On Fri, Dec 4, 2020 at 12:28 AM David Hildenbrand <david@xxxxxxxxxx> wrote:
>
> On 03.12.20 17:22, Muchun Song wrote:
> > The max order page has no buddy page and never merge to other order.
> > So isolating and then freeing it is pointless. And if order == MAX_ORDER
> > - 1, then the buddy can actually be a !pfn_valid() in some corner case?
> > pfn_valid_within(buddy_pfn) that follows would only catch it on archs
> > with holes in zone. Then is_migrate_isolate_page(buddy) might access an
> > invalid buddy. So this is also a bug fix.
> >
> > Fixes: 3c605096d315 ("mm/page_alloc: restrict max order of merging on isolated pageblock")
>
> As just replied to v1, I don't think this is required and the patch

You mean we should remove the Fixes tag? Thanks.

> description can be simplified - e.g., stating that we have/had not such
> users.
>
>
> --
> Thanks,
>
> David / dhildenb
>


-- 
Yours,
Muchun