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Shutemov" Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000009, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Apr 8, 2020 at 11:01 AM Matthew Wilcox wrote: > > From: "Matthew Wilcox (Oracle)" > > I really don't like that this feature is called page poisoning. > We already had something called page poisoning and it's when you detect > a memory error in a page. This is just uninitialised pages. I don't Hi Matthew, Thank you for working on this. Uninitialized struct pages are often zeroed by firmware, and there were a number of implicit assumptions about that memory when I worked on deferred page initializations, this is why it is important to also test when struct pages are specifically set to a pattern that is not all zeroes, something that can happen during kexec, or when memory allocated and freed by kernel during boot. We have caught a good number of bugs using this mechanism. So, this is poisoning, but I agree "page poisoning" name is misleading, as we have this term used in another place. So, lets agree on a better term: how about memmap poisoning (s/page_poisoning/memmap_poisoning/)? Pasha