On Thu, Mar 21, 2013 at 07:26:18AM -0700, H. Peter Anvin wrote: > On 03/21/2013 03:28 AM, Michael S. Tsirkin wrote: > > On Thu, Mar 21, 2013 at 06:59:33PM +1030, Rusty Russell wrote: > >> Another HPA suggestion: that the device be allowed to offer duplicate > >> capabilities, particularly so it can offer a mem and an I/O bar and let > >> the guest decide (Linux guest probably doesn't care?). > >> > >> Cc: H. Peter Anvin <hpa@xxxxxxxxx> > >> Signed-off-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx> > > > > I think guests is exactly the wrong place to decide, > > it really does not know whether it's running on a > > hypervisor with fast IO or fast memory. > > Also, as long as we have an IO BAR, we have problems allocating it. > > So I think we don't need this, see my suggestion > > about fixed IO addresses instead. > > > > The reason to support this is that a guest written to only handle one or > the other doesn't prevent the hypervisor from offering the other to > guests. We probably want to specify that if the guest doesn't care, it > should use the first one offered by the host. > > -hpa What are the configurations where having many ways is helpful? Any examples? _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
