[virtio-dev] RE: [virtio-comment] Re: [PATCH 10/11] transport-pci: Use driver notification PCI capability

Parav Pandit
2023-04-12T05:25:03Z

> From: virtio-comment@lists.oasis-open.org <virtio-comment@lists.oasis-
> open.org> On Behalf Of Michael S. Tsirkin

> > Such registers do not start the VQ data path engines.
> > 1.x spec has done the right thing to have dedicated notification region which
> something an actual pci hw can implement.
>
> okay so.. in fact it turns out existing hardware is not really happy to emulate
> legacy. it does not really fit that well.
> so maybe we should stop propagating the legacy interface to modern hardware
> then.
It is not about current hw, utilize what hw has to offer and utilize what sw has to offer.
The key efficiency is coming by reusing what 1.x has already to offer.

> Add the legacy net header size feature and be done with it.
Hypervisor need to mediate and participate in all life cycle of the device.

One wants to run the block device too. Current proposal with other changes we discussed cover wider case.