[libvirt] libvirt default machine-type guarantees? (was Re: [Qemu-devel] [PATCH RFC] hw/pc: set q35 as the default x86 machine)

On Tue, Jun 05, 2018 at 09:27:46AM +0200, Gerd Hoffmann wrote: > Hi, > > > > Add to that shortcuts like -cdrom > > > stop working, > > > > Maybe is fixable. > > Already fixed for ages. > > > I see marking Q35 as the default machine a first step. > > Maybe the better option is to go the arm route: Just don't define a > default, so users have to specify pc or q35. That will make them notice > there is a world beside 'pc', and we also avoid breaking things > silently. If QEMU removes the default, then libvirt will have to hardcode 'pc' as the default to maintain back compatibility, so I don't think that ends up as a net win