[libvirt] [PATCH 1/2] conf: add debugcon-isa chardev guest interface

[Andrea Bolognani]

On Fri, 2019-01-25 at 14:06 +0000, Nikolay Shirokovskiy wrote:
> On 25.01.2019 16:37, Ján Tomko wrote:
> > On Thu, Jan 24, 2019 at 05:28:59PM +0300, Nikolay Shirokovskiy wrote:
> > > This interface can be used for example by firmware to print
> > > debug messages. Here is domain xml example:
> > > 
> > >    <channel type='file'>
> > >      <source path='/var/log/libvirt/qemu/VM.firmware.log'/>
> > >      <target type='debugcon-isa'/>
> > 
> > IMO 'debugcon' would be enough.
> 
> I followed serial chardev xml. It uses pci-serial, usb-serial etc
> for target type. I think idea is to make it possible to specify
> type when address is not specified (if it is then one can use 
> address type to distinguish). Of course we have only isa-debugcon
> device yet. However I agree that for channel configuration having
> enumeration like spicevm, guesfw, debugcon-isa looks like mixing
> types and subtypes.

Should this be a <channel> at all?

We generally use <serial> for native emulated devices such as
isa-serial, which isa-debugcon seems very closely related to...

Perhaps the best way to hook this up would be

  <serial type='pty'>
    <target type='isa-serial'>
      <model name='isa-debugcon'/>
    </target>
  </serial>

CC'ing Pavel as we looked into this mess together the last time
around, so he might have an opinion on the subject :)

-- 
Andrea Bolognani / Red Hat / Virtualization