Re: [libvirt] Availability of libvirt-4.6.0 Release Candidate 2

On 08/01/2018 04:44 PM, Laine Stump wrote:

> At any rate, there is no perfect solution in sight for the current > release, so the question is whether the new (bad) behavior is better or > worse than the old (also bad) behavior. My understanding is that the old > behavior could lead to a config that had two devices at the same PCI > address, which is definitely undesirable. The new behavior could lead to > the PCI address of a newly-added device being different the next time > the guest is shutdown and restarted. I would tend to prefer the latter, > with the caveat that this new behavior provides a config that works > (from libvirt's domain parsing POV), but might create a strange error in > the guest that would be extremely difficult to troubleshoot (especially > 6 months from now after we've all forgotten about this patch (and > forgotten about the idea that a more complete fix was needed). > > So I'm undecided about my opinion. And when undecided I tend toward > inaction. Now *that's* helpful, isn't it? > Laine is stumped ;-). I'm still stumped over what strange error could be created. How is the virtual {PCI|SCSI} address changing any different from "real hardware" if someone adds something new into their physical system? Or the other

fun adventure, a physical move from location A to location B where someone "forgot" to properly label what went where and upon reassembly things are ordered differently. Consider some (perhaps not so) long ago SCSI devices where you'd need to grab a small, sharp, pin like object to toggle switches to define the address for the device when it got plugged in.