Re: [PATCH v5 0/8] Configurable policy for handling deprecated interfaces

[Richard W.M. Jones]

On Mon, Sep 21, 2020 at 02:54:15PM +0200, Peter Krempa wrote:
> On Mon, Sep 21, 2020 at 13:45:14 +0100, Richard W.M. Jones wrote:
> > Some general comments on using the patch:
> > 
> > * For libguestfs I chose to add
> > 
> >   -compat deprecated-input=reject,deprecated-output=hide
> > 
> >   This is only enabled in developer builds of libguestfs when we
> >   are running qemu directly (not via libvirt).  The patch for
> >   this is attached.
> > 
> > * What's the point/difference in having reject vs crash?
> 
> I'll be adding the following documentation for the qemu.conf entry in
> libvirt controling the feature:
> 
> +# The "reject" option is less harsh towards the VMs but some code paths 
> ignore
> +# errors reported by qemu and thus it may not be obvious that a deprecated
> +# command/field was used, thus it's suggested to use the "crash" option 
> instead.

I'm not sure if libguestfs should use reject or crash.  But since most
of the benefit of this is going to be in detecting deprecated CLI
parameters in future, reject should be sufficient for us.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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