On Thu, Nov 18, 2010 at 09:22:02AM +0100, Gerd Hoffmann wrote: > On 11/18/10 09:09, Gleb Natapov wrote: > >On Wed, Nov 17, 2010 at 08:00:08PM +0200, Michael S. Tsirkin wrote: > >>>>> If so: does qemu > >>>>>emulate this correctly? > >>>> > >>>>It mostly does. > >>> > >>>I doubt it actually enables/disables the legacy vga ports. > >> > >>I'll check when I have the time. We can fix it if it doesn't, > >> > >So many guests (all of them?) just assume that vga ports and > >framebuffer is there. So what "fixing" this will buy us? > > Nothing? > > Certainly not for the qemu standard vga. The only way for guests is > to drive that one is via legacy vga ports and vesa vga bios. > Hotplug is never ever going to work here. > Also the vga memory window @ 0xa0000 with the piix chipset > interactions is good for some extra fun ... > > cirrus might be fixable to be hotpluggable. It also can be > programmed via mmio bar instead of legacy vga ports, so having two > cirrus cards in one system might be possible to get work. I doubt > it is worth the trouble though.
We will need to fix this for proper pci memory management, anyway. > I still think that vga cards should simply be flagged to be not > hot-pluggable. > > cheers, > Gerd Send a patch. -- MST