Messages in this thread | | | Date | Thu, 2 Apr 2015 18:04:00 -0700 (PDT) | From | David Rientjes <> | Subject | Re: [patch v2 4/4] mm, mempool: poison elements backed by page allocator |
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On Tue, 31 Mar 2015, Andrey Ryabinin wrote:
> > We don't have a need to set PAGE_EXT_DEBUG_POISON on these pages sitting > > in the reserved pool, nor do we have a need to do kmap_atomic() since it's > > already mapped and must be mapped to be on the reserved pool, which is > > handled by mempool_free(). > > > > Hmm.. I just realized that this statement might be wrong. > Why pages has to be mapped to be on reserved pool? > mempool could be used for highmem pages and there is no need to kmap() > until these pages will be used. > > drbd (drivers/block/drbd) already uses mempool for highmem pages: >
Yes, you're exactly right, I didn't see this because the mempool is created in one file and then solely used in another file, but regardless we still need protection from this usecase.
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