Re: [PATCH 4/5] hw/nvme: do not auto-generate uuid

[Christoph Hellwig]

On Wed, Apr 20, 2022 at 07:51:32AM +0200, Klaus Jensen wrote:
> > So unlike the EUI, UUIDs are designed to be autogenerated even if the
> > current algorithm is completely broken.  We'd just need to persist them.
> > Note that NVMe at least in theory requires providing at least on of
> > the unique identifiers, and the UUID is the only one designed to be
> > autogenerated in a distributed fashion.
> 
> I understand, but it boils down to the fact that we do not have a
> general method of storing "metadata" like this persistently.
> 
> But maybe it is time that we come up with something to do this.

If we can't make the persistent uniqueue identifiers persistent and
unique, we should not provide them.  While NVMe does require a
namespace to report at least one of the three identifies, the failure
mode for now having one is much more graceful than providing one that
is not unique or not persistent.