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    Subjectget_user_pages question
    Hi,
    I have been tryin to use get_user_pages() on malloced memory and get the
    list of pages but it does not work as
    I expected:
    1. malloc a buffer in user space
    2. issue ioctl, invoke get_user_pages() and save the page descriptors I
    obtained.
    3. at a later time, issue another ioctl, invoke get_user_pages() again
    and save another copy of the page descriptors.
    4. Compare the two lists of page descriptors. They're not all the same.

    Apparently some pages were discarded and the subsequent page fault
    brought a new page. I expected the original page to be in the swap cache
    and get the old page again. I repeated the experiment but before the
    first ioctl I wrote something to all the pages but got the same results.
    I used 2.4.21-4 (RH AS 3.0).

    Can anyone clarify?
    thanks
    Eli
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