• Oliver O'Halloran's avatar
    powerpc/mm: Ensure "special" zones are empty · 3079abe5
    Oliver O'Halloran authored
    The mm zone mechanism was traditionally used by arch specific code to
    partition memory into allocation zones. However there are several zones
    that are managed by the mm subsystem rather than the architecture. Most
    architectures set the max PFN of these special zones to zero, however on
    powerpc we set them to ~0ul. This, in conjunction with a bug in
    free_area_init_nodes() results in all of system memory being placed in
    ZONE_DEVICE when enabled. Device memory cannot be used for regular kernel
    memory allocations so this will cause a kernel panic at boot. Given the
    planned addition of more mm managed zones (ZONE_CMA) we should aim to be
    consistent with every other architecture and set the max PFN for these
    zones to zero.
    Signed-off-by: default avatarOliver O'Halloran <oohall@gmail.com>
    Reviewed-by: default avatarBalbir Singh <bsingharora@gmail.com>
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    3079abe5
mem.c 14.9 KB