Re: [PATCH] igvm: add command line parameter support

["Daniel P. Berrangé" <berrange@redhat.com>]

On Thu, Oct 01, 2026 at 10:08:34AM +0200, Markus Armbruster wrote:
> Luigi Leonardi <leonardi@redhat.com> writes:
> 
> > Add a "cmdline" property to the igvm-cfg object and a handler for the
> > IGVM_VHT_COMMAND_LINE directive, which copies the string into the
> > parameter area the directive points at.
> >
> > This command line is intended for the component running at VMPL0, such
> > as SVSM, rather than for the guest OS, whose own command line still
> > comes from -append. SVSM can use it to select the serial port it logs
> > to, for example.
> >
> > Signed-off-by: Luigi Leonardi <leonardi@redhat.com>
> 
> [...]
> 
> > diff --git a/qapi/qom.json b/qapi/qom.json
> > index 5895c97750..d56bdef561 100644
> > --- a/qapi/qom.json
> > +++ b/qapi/qom.json
> > @@ -1004,11 +1004,15 @@
> >  #
> >  # @file: IGVM file to use to configure guest
> >  #
> > +# @cmdline: command line for the software loaded from the IGVM file,
> > +#     rather than for the guest OS.  Ignored if the IGVM file does
> > +#     not ask for one.  (since 11.2)
> > +#
> >  # Since: 10.1
> >  ##
> >  { 'struct': 'IgvmCfgProperties',
> >    'if': 'CONFIG_IGVM',
> > -  'data': { 'file': 'str' } }
> > +  'data': { 'file': 'str', '*cmdline': 'str' } }
> >  
> >  ##
> >  # @SevCommonProperties:
> 
> How is @cmdline going to be parsed?  By a shell?

This is something passed to the guest workflow. ie a kernel command
line string.

> For what it's worth, MigrationExecCommand uses ['str'].  Such values can
> be passed to exec()-like functions without parsing.

In this case we should treat 'cmdline' as an opaque strnig and not
try to place any semantics on its expected syntax.

With regards,
Daniel
-- 
|: https://berrange.com       ~~        https://hachyderm.io/@berrange :|
|: https://libvirt.org          ~~          https://entangle-photo.org :|
|: https://pixelfed.art/berrange   ~~    https://fstop138.berrange.com :|