• Jan Beulich's avatar
    agp: two-stage page destruction issue · da503fa6
    Jan Beulich authored
    besides it apparently being useful only in 2.6.24 (the changes in 2.6.25
    really mean that it could be converted back to a single-stage mechanism),
    I'm seeing an issue in Xen Dom0 kernels, which is caused by the calling
    of gart_to_virt() in the second stage invocations of the destroy function.
    I think that besides this being a real issue with Xen (where
    unmap_page_from_agp() is not just a page table attribute change), this
    also is invalid from a theoretical perspective: One should not assume that
    gart_to_virt() is still valid after unmapping a page. So minimally (keeping
    the 2-stage mechanism) a patch like the one below would be needed.
    Signed-off-by: default avatarDave Airlie <airlied@redhat.com>