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    SubjectRe: [PATCH] [BUGFIX] rmap: remove anon_vma check in page_address_in_vma()
    On 04/22/2010 10:08 PM, Naoya Horiguchi wrote:
    > Currently page_address_in_vma() compares vma->anon_vma and page_anon_vma(page)
    > for parameter check, but in 2.6.34 a vma can have multiple anon_vmas with
    > anon_vma_chain, so current check does not work. (For anonymous page shared by
    > multiple processes, some verified (page,vma) pairs return -EFAULT wrongly.)
    >
    > We can go to checking all anon_vmas in the "same_vma" chain, but it needs
    > to meet lock requirement. Instead, we can remove anon_vma check safely
    > because page_address_in_vma() assumes that page and vma are already checked
    > to belong to the identical process.
    >
    > Signed-off-by: Naoya Horiguchi<n-horiguchi@ah.jp.nec.com>
    > Cc: Andrew Morton<akpm@linux-foundation.org>
    > Cc: Rik van Riel<riel@redhat.com>
    > Cc: Andi Kleen<andi@firstfloor.org>

    Reviewed-by: Rik van Riel <riel@redhat.com>


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