On Thu, 5 Jun 2014 12:11:55 -0400
Don Slutz <address@hidden> wrote:
This is a pc & q35 only machine opt. One use is to allow for more
ram in a 32bit guest for example:
-machine pc,max-ram-below-4g=3.75G
If you add enough PCI devices then all mmio for them will not fit
below 4G which may not be the layout the user wanted. This allows
you to increase the below 4G address space that PCI devices can use
(aka decrease ram below 4G) and therefore in more cases not have any
mmio that is above 4G.
For example using "-machine pc,max-ram-below-4g=2G" on the command
line will limit the amount of ram that is below 4G to 2G.
Signed-off-by: Don Slutz <address@hidden>
this patch would look better if rebased on top of
http://lists.gnu.org/archive/html/qemu-devel/2014-06/msg00133.html
and would use PCMachine type to add PC specific "max-ram-below-4g" property.