On Mon, Jun 02, 2014 at 02:00:14PM +0100, David Woodhouse wrote:
Unless CONFIG_MALLOC_UPPERMEMORY is turned off, we expect to use the space between the top of option ROMs and the bottom of our own BIOS code as a stack. OVMF was previously marking the whole region from 0xC0000 to 0xFFFFF read-only before invoking our Legacy16Boot method. Read-only stack considered harmful.
Version 0.98 of the CSM spec adds the UmaAddress and UmaSize fields which allow the CSM to specify a memory region that needs to be writeable, so provide that information.
Thanks. I committed this patch.