Re: Command line QAPIfication and -readconfig

[Andrea Bolognani <abologna@redhat.com>]

On Wed, 2020-11-11 at 11:35 +0100, Kevin Wolf wrote:
> Am 11.11.2020 um 11:14 hat Daniel P. Berrangé geschrieben:
> > Normally we would not mark something as deprecated unless its replacement
> > is ready, because telling people "stop using this but the replacement
> > doesn't exist yet" is not a nice message as there is no action users can
> > take to deal with the deprecation.
> 
> But there is a replacement: Put everything back into the command line
> and keep it in a shell script. Config files with -readconfig were never
> complete enough to fully describe a VM, so it's not too unlikely that
> you'll already have that script anyway.

This is correct: in fact...

> > We might question whether -readconfig has any users but I would note
> > that our own documentation illustrates its usage, and provides several
> > example configs
> > 
[...]
> > config/mach-virt-graphical.cfg:#     -readconfig mach-virt-graphical.cfg \
> > config/mach-virt-serial.cfg:#     -readconfig mach-virt-serial.cfg \
> > config/q35-emulated.cfg:#     -readconfig q35-emulated.cfg
> > config/q35-virtio-graphical.cfg:#     -readconfig q35-virtio-graphical.cfg
> > config/q35-virtio-serial.cfg:#     -readconfig q35-virtio-serial.cfg \
[...]

... these configuration files, which I contributed some time ago, all
start with something along the lines of

  # Usage:
  #
  #   $ qemu-system-aarch64 \
  #     -nodefaults \
  #     -readconfig mach-virt-serial.cfg \
  #     -display none -serial mon:stdio \
  #     -cpu host

because it was simply impossible to provide QEMU with all the
settings necessary to obtain the desired virtual hardware using the
configuration file only.

-- 
Andrea Bolognani / Red Hat / Virtualization