Re: [PATCH 1/2] mm: hwpoison: don't drop slab caches for offlining non-LRU page

[Yang Shi]

On Mon, Aug 16, 2021 at 12:38 PM Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
>
> On Mon, Aug 16, 2021 at 11:09:08AM -0700, Yang Shi wrote:
> > But the most disappointing thing is all the effort doesn't make the page
> > offline, it just returns:
> >
> > soft_offline: 0x1469f2: unknown non LRU page type 5ffff0000000000 ()
>
> It's a shame it doesn't call dump_page().  There might be more
> interesting information somewhere in struct page that would help us
> figure out what kind of page it was in your environment.  For example,
> it might be a page table page or a page allocated for vmalloc(), and
> in both those cases, there are things we might be able to do (we'd
> certainly be able to figure out that it isn't worth shrinking slab!)

Yes,  dump_page() could provide more information to us. I could add a
new patch or just update this patch to call dump_page() if offline is
failed if the hwpoison maintainer agrees to this as well.