Re: [Qemu-devel] [PATCH] virtio-pci: Fix endianness of virtio config

[Alexander Graf]

On 10.01.2012, at 23:52, Alexander Graf wrote:

> 
> On 10.01.2012, at 23:49, Benjamin Herrenschmidt wrote:
> 
>> On Tue, 2012-01-10 at 23:41 +0100, Alexander Graf wrote:
>>> 
>>> No. Libhw shouldn't be able to know anything about target endianness.
>>> If a device is as brokenly spec'ed as virtio and is coupled to the
>>> "main CPU endianness", it clearly belongs with the CPU, not into
>>> libhw.
>> 
>> Ok, can you guys solve this and tell me what I should do ? :-)
> 
> Your patch is fine. I also wrote up another patch that fixes the memcpy() in 
> virtio.c so you patch actually works on x86 too. I sent it to you, so please 
> include it in your next submission.
> 
> I would heavily veto against keeping virtio-pci in libhw though if it depends 
> on the target endianness. PCI devices don't know about CPUs. Period.

The only thing I could imagine doable would be basically 2 different variants 
of virtio-pci that happen to expose the same PCI ID, but are initialized 
differently by a qdev property. We could then have the alias to normal 
virtio-pci device names in target specific code, but the actual device code in 
libhw.


Alex