Re: [PATCH v10 08/10] admin: command list discovery

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Mar 02, 2023 at 04:09:29PM -0500, Stefan Hajnoczi wrote:
> Is the purpose of VIRTIO_ADMIN_CMD_LIST_USE so that new commands can be
> added that are mandatory for device operation. Failure to include them
> in the VIRTIO_ADMIN_CMD_LIST_USE command terminates device
> initialization with an error?

Or, switches the device to some legacy mode.

> Are commands evolved by defining flag/version bits in the command
> specific data struct? For example, if a new field needs to be added to a
> command and a 0 value carries a meaning (so it cannot simply be added to
> the end of the existing struct with backwards compatibility).
> 

commands expect to be evolved by extending the command specific
structure at the tail. this is why I spent so much time
on that in the text. if that does not work a new command will
work.

-- 
MST