Hi,
thank you for your report - and being upstream queued for qemu 2.9 already I 
think we can take that as backport into zesty without too much discussion.

But this "argument" is already a thin line and it will get thinner when it 
would come to SRUs.
By the Argument I mean "This behaviour change is not actually a bug since no 
assumptions should be
made on DT ordering. [...] It is expected to make things easier when porting 
existing applications to power.".

I read through the thread and I totally understand the need why this got 
"reverted" now.
But trivializing this - either it is:
- not an important behavior change (then this fix would not exist)
- an important behavior change (then it is not really SRUable)

The latter means that everybody on Xenial/Yakkety where the current reversed 
order is released have already adapted their setups, guests, device names, ...
If they went with device labels and such due to the initial error they won't 
see a change, but e.g. naming of network devices might change if they are not 
running with persistent device naming (Note Ubuntu does so for net it would be 
e.g. enp0s1 no matter what, but I think e.g. disk device names would change 
order).

That said SRUing this would break all those then right?

TL;DR: "either it is not important to SRU or it is, but then it would be a non 
SRUable behavior change".
Open for discussion, but these are the thoughts going through my mind at the 
moment.

For Zesty I think we are fine, the next Qemu release would change it just the 
same.
But please discuss with me what and why we should exactly do with 
Xenial/Yakkety.

A zesty fix is currently building for testing and verification in 
https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/2543
It would be great if you could confirm that achieves what you want with a test 
from your side.

** Also affects: qemu (Ubuntu Zesty)
   Importance: Undecided
     Assignee: Taco Screen team (taco-screen-team)
       Status: Triaged

** Also affects: qemu (Ubuntu Yakkety)
   Importance: Undecided
       Status: New

** Also affects: qemu (Ubuntu Xenial)
   Importance: Undecided
       Status: New

** Changed in: qemu (Ubuntu Xenial)
       Status: New => Incomplete

** Changed in: qemu (Ubuntu Yakkety)
       Status: New => Incomplete

** Changed in: qemu (Ubuntu Zesty)
       Status: Triaged => In Progress

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https://bugs.launchpad.net/bugs/1670481

Title:
  Backport "populate PCI DT in reverse order" patch

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