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    SubjectRe: [PATCH] mm: fix page_mkclean_one
    On Wed, Dec 27, 2006 at 10:20:20PM -0700, Gordon Farquharson wrote:
    > I have run the program a few times, and the output is pretty
    > consistent. However, when I increase the target size, the difference
    > between the expected and actual values is larger.
    > Written as (749)935(738)
    > Chunk 1113 corrupted (1-1455) (2965-323)
    > Expected 89, got 93

    This is not the corruption Linus is after. Note that the corruption starts
    at offset '1'. Also note that:

    89 = 1113 & 255
    93 = 1113 & 255 | (1113 >> 8)

    and if you look at glibc's memset() function, you'll notice that's exactly
    what you expect if you pass a non-8bit value to it. Ergo, what you're
    seeing is utterly expected given glibc's memset() implementation on ARM.

    Fixing Linus' test program to pass nr & 255 to memset results in clean
    passes on 2.6.9 on TheCus N2100 (IOP8032x) and StrongARM
    machines (as would be expected.)

    Russell King
    Linux kernel 2.6 ARM Linux -
    maintainer of:
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      Last update: 2006-12-28 11:17    [W:0.022 / U:3.048 seconds]
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