On Mon, 7 Jun 2010 15:27:56 +0100, Michael Brown wrote > On Monday 07 Jun 2010 15:19:16 Guo-Fu Tseng wrote: > > > 3. By increasing the total memory footprint beyond 1MB, you lose the > > > guarantee of residing entirely within a region with A20=0. iPXE will > > > work in a region with A20=1, but gPXE may fail. > > > > By placing the heap to the highest memory address, we can ensure that > > all addresses other than heap would still be at region with A20=0. > > Since gPXE have not apply your A20 patchset right now. > > > > This is the part that I'm not sure, have not traced all your code yet. > > But I'm guessing that the A20=0 limitation is for 16-bit code only. > > And the parts that uses heap which written in C are running on 32-bit > > protected-mode(for arch i386 with librm). So I'm hoping that it can > > make gPXE safer this way. > > No; the A20=0 limitation in gPXE applies to 32-bit code as well as 16- > bit code. > > Michael Ahh.. I should do more deep reading than...
Guo-Fu Tseng _______________________________________________ gPXE-devel mailing list [email protected] http://etherboot.org/mailman/listinfo/gpxe-devel
