On 10.01.2012, at 22:04, Benjamin Herrenschmidt wrote: > On Tue, 2012-01-10 at 21:46 +0100, Alexander Graf wrote: >> On 10.01.2012, at 21:35, Andreas Färber wrote: >> >>> Am 10.01.2012 21:30, schrieb Alexander Graf: >>>> Maybe the RTAS callbacks really want you to return stuff in little >> endian? >>> >>> IIRC all RTAS callbacks need to be in the same bitness and >> endianness >>> (MSR LE+SB) as when instantiating RTAS from OF. >> >> Sure, the question is how the PCI controller is wired up usually. Just >> because RTAS works in native endianness doesn't mean that endianness >> of the actual device access isn't defined differently. > > Eugh... you guys don't get it :-) This is -not- about the PCI > configuration space, but the virtio configuration space which is a > slightly different thing (PCI config space works with what's there at > the moment). > > So this has nothing to do with e1000 or any other emulated device like > that, but it does have to do with virtio-blk for example. Ah, yeah, sorry, didn't get that part :). > The way virtio works is that the PIO BAR is split into two parts. The > first part (header) is a set of what's basically pseudo MMIO registers > that are little endian. The second part is device-specific an is ... > guest native endian. (Yeah it's horrible, I know). > > This is how it's specified in the virtio spec and how Linux expects it, > with this patch, I can boot an existing fedora 16 with virtio-blk for > example. Here's the thing that I don't understand. What exactly is breaking for you? I tried -M pseries on a ppc box and on an x86 box and both times was able to see /dev/vda. Alex -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
