[libvirt] [PATCH] qemu: Ignore missing query-migrate-parameters

[Erik Skultety]

On Thu, Apr 27, 2017 at 09:22:14AM +0200, Jiri Denemark wrote:
> On Thu, Apr 27, 2017 at 08:49:30 +0200, Erik Skultety wrote:
> > On Wed, Apr 26, 2017 at 11:25:46PM +0200, Jiri Denemark wrote:
> > > Trivially no migration parameters are supported when
> > > query-migrate-parameters QMP command is missing. There's no need to
> > > report an error in such case especially when doing so breaks
> > > compatibility with old QEMU.
> >
> > I'd suggest adjusting the commit message a bit, since the important part is
> > that there's a regression, the migration should work regardless of the presence
> > of the QMP command, and without your patch, it doesn't.
>
> Migration with old QEMU which does not support query-migrate-parameters
> would fail because the QMP command is called unconditionally since the
> introduction of TLS migration. Previously it was only called if the user
> explicitly requested a feature which uses QEMU migration parameters. And
> even then the situation was not ideal, instead of reporting an
> unsupported feature we'd just complain about missing QMP command.
>
> Trivially no migration parameters are supported when
> query-migrate-parameters QMP command is missing. There's no need to
> report an error if it is missing, the callers will report better error
> if needed.
>
> Is this better?

Very much, yep.

Erik

>
> Jirka
>
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