[libvirt] [PATCH 6/4] qemu: address: Remove QEMU_CAPS_DEVICE usage

[Laine Stump]

On 05/18/2016 07:53 AM, Cole Robinson wrote:
> Kind of. Prior to patch #2, the test suite output was correct (no addresses),
> it's what we were returning via domxml-from-native. After patch #2, the test
> suite output was wrong for all real world usage; it didn't change because it
> was only hitting a !QEMU_CAPS_DEVICE code path
>
> So the potentially contentious bit is that patch #2 changes domxml-from-native
> output to contain addresses, however that's exactly the same result that will
> happen when the XML would eventually be defined anyways, so it's effectively
> the same result as pre-patch #2 anyways. If we think of domxml-from-native as
> telling the user 'this is exactly what libvirt thinks that command line is'
> then we are now giving more accurate results
>
> Let me know if that still warrants the ACK

My opinion is that this is a change for the better. While it is true 
that this could lead to XML that potentially shows different PCI 
addresses than what would have been auto-assigned by qemu when presented 
with the original commandline, it *is* showing the addresses that would 
be auto-allocated by libvirt if you had fed the "un-addressified" XML to 
libvirt - so at least the user will get a warning rather than being 
surprised at runtime. And it's not as if the output of 
domxml-from-native has ever produced anything even close to the correct 
XML in any real world situation. (dreadkopp in public #virt pastebin'ed 
an example last night - 90% of it was translated directly into 
<qemu:arg> elements).