• Russell King's avatar
    ARM: Fix broken highmem support · dde5828f
    Russell King authored
    Currently, highmem is selectable, and you can request an increased
    vmalloc area.  However, none of this has any effect on the memory
    layout since a patch in the highmem series was accidentally dropped.
    Moreover, even if you did want highmem, all memory would still be
    registered as lowmem, possibly resulting in overflow of the available
    virtual mapping space.
    The highmem boundary is determined by the highest allowed beginning
    of the vmalloc area, which depends on its configurable minimum size
    (see commit 60296c71 for details on
    We should create mappings and initialize bootmem only for low memory,
    while the zone allocator must still be told about highmem.
    Currently, memory nodes which are completely located in high memory
    are not supported.  This is not a huge limitation since systems
    relying on highmem support are unlikely to have discontiguous memory
    with large holes.
    [ A similar patch was meant to be merged before commit 5f0fbf9e
      and be available  in Linux v2.6.30, however some git rebase screw-up
      of mine dropped the first commit of the series, and that goofage
      escaped testing somehow as well. -- Nico ]
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    Reviewed-by: default avatarNicolas Pitre <nico@marvell.com>
setup.h 5.07 KB