Re: [PATCH 08/12] tests/9pfs: refactor test names and test devices

[Christian Schoenebeck]

On Donnerstag, 1. Oktober 2020 16:04:39 CEST Paolo Bonzini wrote:
> >> You're right, this is in fact also a problem for virtio-blk and virtio-
net:
> >>     /* FIXME: every test using these two nodes needs to setup a
> >>     
> >>      * -drive,id=drive0 otherwise QEMU is not going to start.
> >>      * Therefore, we do not include "produces" edge for virtio
> >>      * and pci-device yet.
> >>     
> >>     */
> >>     
> >>     /* FIXME: every test using these nodes needs to setup a
> >>     
> >>      * -netdev socket,id=hs0 otherwise QEMU is not going to start.
> >>      * Therefore, we do not include "produces" edge for virtio
> >>      * and pci-device yet.
> >>      */
> >> 
> >> I still think we should do it like this, because it's closer to the way
> >> that libqos will work long term.
> > 
> > Could you please elaborate why that long term plan bites with the working
> > solution I provided? [patches 1 and 2]
> 
> Because the long term plan is to have a socket/plug mechanism for
> backends where the device can provide a default backend to plug.

Ok, obviously I don't know the details of that future socket/plug plan, but 
what I could also imagine for the long-term: allowing to optionally define 
'config' nodes as subnodes of devices. Maybe that's similar to what you had in 
mind with that socket/plug model.

> The suggested solution is all good for *a different use case*, namely to
> test the same device with different options.  It is just wrong for the
> purpose of selecting a frontend.
> 
> It occurred to me that you could also add a default backend to the
> command line with "-fsdev" (in the libqos driver), and use -set in the
> test to override it.  This is ugly (-set is ugly!) but it would let you
> keep the tests, so it would probably be the best solution.

Ok, I'll have a look at that '*-set' alternative tomorrow.

But on doubt: I will simply disable those the implied pci and virtio tests for 
the time being.

I need the 'local' backend tests and have to move on; they are of much more 
value than those 2 implied pci and virtio tests.

Best regards,
Christian Schoenebeck