[libvirt] [PATCH 0/1] bhyve: Make LPC slot number configurable

[Ivan Mishonov]

On 08/13/2018 11:00 AM, Daniel P. Berrangé wrote:

> On Sun, Aug 12, 2018 at 08:22:08PM +0400, Roman Bogorodskiy wrote:
>>    Ivan Mishonov wrote:
>>
>>> Yes, that makes sense. I'll try to find some time next week to redo my
>>> code and send another patch. Since my time for working on libvirt is
>>> very limited can you confirm that the LPC configuration should look like
>>> this:
>>>
>>>      <controller type="isa-bridge" index="0">
>>>          <address type="pci" domain="0" bus="0" slot="NNN" function="0"/>
>>>      </controller>
>> This looks reasonable to me. However, it adds some corner cases we need to
>> handle:
>>
>> 1. I'm wondering if we should still default to 31 if this entry is not specified?
>> We can generate this entry when post-processing XML, but I'm not sure
>> what's the best way to handle upgrades for the existing domains...
> It depends if the BHyve driver is at a point where you consider stable
> upgrades important or not. It could be valid for you to just change the
> default to 31 if you think its better and upgrade stability is not
> required yet.
I decided to check what vm-bhyve does. 
https://github.com/churchers/vm-bhyve/blob/master/lib/vm-run#L367. They 
seem to always place LPC at slot 31 so I guess it's safe to move it
>
>> 2. According to bhyve(8) manual page, lpc is only supported on bus 0, so
>> need to add 'isa-bridge' specific validation to check that.
> If its only supported in 1 address, then arguably you don't need to add
> this at all - just fix the historically mistaken use of 31 in the code
> and leave it out of XML.
Yes, we might not need that option at all
>
> Regards,
> Daniel