Re: [libvirt] [PATCH 6/8] domain: Make <address type='pci'/> request address allocation
On 03/21/2016 02:59 PM, Cole Robinson wrote:
On 03/21/2016 02:44 PM, John Ferlan wrote:
> Would this be useful if "multifunction='on'" without specifying an
> address? e.g.:
>
> <address type='pci' multifunction='on'>
>
Maybe? Honestly I don't know much about when multifunction should be used.
I doubt that would ever be useful, since you need to match the multiple
devices that are plugged into the slot by specifying a matching
bus/slot, (the function# must always be 0 for the device that has
"multifunction" option specified - it is supposed to be turned on for
function 0 on any slot that has multiple functions in use. It seems to
me that multifunction could have been left out of libvirt's XML
completely, with 100% success of automatically turning it on at the
correct time (since you *always* know ahead of time whether or not there
will be multiple functions for a slot - hotplugging of multiple
functions into a slot isn't supported, and in the eventuality that we do
support it, it will only be supported by plugging in all the functions
at once.) Several years too late for that now though :-P )