Re: [External] Re: [PATCH] mm: hugetlb: fix a race between memory-failure/soft_offline and gather_surplus_pages
From: Muchun Song
Date: Wed Apr 21 2021 - 04:58:45 EST
On Wed, Apr 21, 2021 at 4:49 PM Oscar Salvador <osalvador@xxxxxxx> wrote:
> On Wed, Apr 21, 2021 at 04:41:10PM +0800, Muchun Song wrote:
> > But softoffline does not set page hwpoison before
> > __get_hwpoison_page(). So the page still can be
> > allocated. Right?
> Yep, soft_offline() only marks the page as hwpoison once the page has been
> fully contended and no other use is possible.
> But yeah, hugetlb is a bit trickier in that regard.
> This needs fixing in there.
It is OK to fix it in softoffline/memory-failure.
I just want to expose the race. Thanks.
> Oscar Salvador
> SUSE L3