Re: [PATCH v1 3/7] mm: rename and move page_is_poisoned()

On Wed, 5 May 2021 15:45:47 +0200
Michal Hocko [off-list ref] wrote:

On Wed 05-05-21 15:39:08, David Hildenbrand wrote:

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Long story short, this should be good enough for the cases we actually can
handle? What am I missing?  

I am not sure I follow. My point is that I fail to see any added value
of the check as it doesn't prevent the race (it fundamentally cannot as
the page can be poisoned at any time) but the failure path doesn't
put_page which is incorrect even for hwpoison pages.  

Oh, I think you are right. If we have a page and return NULL we would leak a
reference.

Actually, we discussed in that thread handling this entirely differently,
which resulted in a v7 [1]; however Andrew moved forward with this
(outdated?) patch, maybe that was just a mistake?

Yes, I agree we should revert that patch for now.  

OK, Let me send the revert to Andrew.

Got this!
Anyway, I will try to post a new patch for this issue based on the previous patch v7.

Thanks!
Aili Yao