[libvirt] [PATCH v2 1/3] storage: Fix existing parent check for vHBA creation

[John Ferlan]

[...]
>>
>> Because it hasn't really been characterized as a misconfiguration
>> previously. I doubt anyone outside of QE has ever done something like
>> this as there's no reason to do so. If they want to use the HBA they'd
>> use the 'scsi_host' format.
>>
>> IMO: something with 'fc_host' what uses the HBA wwnn/wwpn is
>> misconfigured because it's not a vHBA then, but there's been no attempt
>> to prohibit that configuration, hence the current mess.
>>
>> I'd be perfectly fine with turning this particular bz/check into - don't
>> configure things this way because it's not how it's supposed to work. If
>> you want a storage pool backed to an HBA, then use the scsi_host syntax.
>> If you want a vHBA/NPIV then use the fc_host syntax.
> 
> After re-reading the docs, I'm quite convinced we should enforce the
> configuration, hopefully it would clean up the code significantly.
> 
> Erik
> 

Not sure how much gets "cleaned up" as only the Create/Destroy storage
pool code paths need to know.

While I agree in principle that it's incorrect configuration, it has
been allowed and removing something that was allowed at one time gets
into a gray area.

For the destroy path, we'd still have to be able to handle both since a
storage pool could exist prior to disallowing the create path to work
and we'd have no way to destroy the pool.

For the create path, it's an adjustment "post" in patch3 to add checks
for whether the parent or the parent found by wwnn/wwpn is an HBA, then
disallow the startup.

In any case, I'll post a new series with patch1 adjust as requested and
patch 3 split to handle the two things - the first being checking the
parent_name validity and the second to ensure the @name is not an HBA

John