On Fr, 2015-07-03 at 08:45 +0200, Paolo Bonzini wrote:
On 29/06/2015 10:53, Gerd Hoffmann wrote:
virtio version 1.0 registers can (and actually do in the qemu implementation) live in mmio space. So we must run the blk and scsi virtio drivers in 32bit mode, otherwise we can't access them.
This also allows to drop a bunch of GET_LOWFLAT calls from the virtio code in the following patches.
This isn't really necessary though. The config access capability exists for this reason. At least as a follow up it would be nice to add a switch.
Just saw mst's patch implementing it in qemu. I'll have a look.
I think I want keep the virtio drivers as 32bit drivers. The modern virtio bar is a 64bit though, so accessing via config access capability might be needed even for the 32bit drivers in case it is mapped above 4G ...