On Mon, Jun 10, 2013 at 07:14:45PM +1000, Peter Crosthwaite wrote: > Hi, > > On Mon, Jun 10, 2013 at 3:27 PM, Gerd Hoffmann <kra...@redhat.com> wrote: > > Hi, > > > >> Maybe instead (or in addition to), we should provide a dummy > >> read or write functions -- instead of fixing each such occurence > >> to use its own dummy function > > > > Makes sense, especially for write where we can just ignore what the > > guest attempts to write. Not sure we can have a generic handler for > > reads. Maybe two, one which returns 0xff and one which returns 0x00. > > > > FWIW, I have one in my tree that qemu_log(LOG_GUEST_ERROR's such > accesses that I use for unimplemented devices. It's worthwhile to trap > such accesses and speaking for the Xilinx LQSPI case, my preference is > for some form of failure rather than silent write-ignore. And can we > have an option where a invalid writes have consistent behavior with > unassigned accesses? > > Regards, > Peter
Probably not a good idea. Ignoring unassigned addresses is very handy for compatibility: we can run new guests on old qemu and They don't crash or log errors. > > cheers, > > Gerd > > > >
