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    SubjectRe: [PATCH] eCryptfs - use page_alloc not kmalloc to get a page of memory
    On Mon, 28 Jul 2008 11:13:03 -0500
    Eric Sandeen <> wrote:

    > With SLUB debugging turned on in 2.6.26, I was getting memory corruption
    > when testing eCryptfs. The root cause turned out to be that eCryptfs
    > was doing kmalloc(PAGE_CACHE_SIZE); virt_to_page() and treating that
    > as a nice page-aligned chunk of memory. But at least with SLUB debugging
    > on, this is not always true, and the page we get from virt_to_page does
    > not necessarily match the PAGE_CACHE_SIZE worth of memory we got from
    > kmalloc.
    > My simple testcase was 2 loops doing "rm -f fileX; cp /tmp/fileX ." for
    > 2 different multi-megabyte files. With this change I no longer see
    > the corruption.

    The fix applies to both 2.6.25 and to 2.6.26 and appears to be needed
    in both kernel versions, so I have tagged it for backporting into both.

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      Last update: 2008-07-28 22:39    [W:0.042 / U:8.368 seconds]
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