• G
    pc: allow raising low memory via max-ram-below-4g option · 8156d480
    Gerd Hoffmann 提交于
    This patch extends the functionality of the max-ram-below-4g option
    to also allow increasing lowmem.  Use case: Give as much memory as
    possible to legacy non-PAE guests.
    
    While being at it also rework the lowmem calculation logic and add a
    longish comment describing how it works and what the compatibility
    constrains are.
    
    Note:  This is a incompatible change.  When setting max-ram-below-4g to
    a value larger than 3.5G (or 3G with gigabyte alignment) it has no
    effect on older qemu versions: qemu silently ignores it.  With the patch
    applied it actually has an effect and changes the ram layout.  Highly
    unlikely to hit in practive though as there is no reason start old qemu
    versions that way.
    Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
    Reviewed-by: NEduardo Habkost <ehabkost@redhat.com>
    Message-Id: <1464857305-26675-1-git-send-email-kraxel@redhat.com>
    Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
    8156d480
pc.c 60.1 KB