Messages in this thread | | | From | David Hildenbrand <> | Subject | Re: [PATCH v1 3/7] mm: rename and move page_is_poisoned() | Date | Wed, 5 May 2021 15:39:08 +0200 |
| |
>> 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in that thread handling this entirely differently, which resulted in a v7 [1]; however Andrew moved forward with this (outdated?)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.
Regarding the race comment: AFAIU e.g., [2], it's not really a problem with a race, but rather some corner case issue that can happen if we fail in memory_failure().
[1] https://lkml.kernel.org/r/20210406104123.451ee3c3@alex-virtual-machine [2] https://lkml.kernel.org/r/20210331015258.GB22060@hori.linux.bs1.fc.nec.co.jp
-- Thanks,
David / dhildenb
| |