Re: [GIT PULL] Native Linux KVM tool for 3.1

[Ingo Molnar <mingo@elte.hu>]

* Avi Kivity <avi@redhat.com> wrote:

> On 07/25/2011 01:03 PM, Ingo Molnar wrote:
> >>  >  Then look at the actual drivers and interfaces within tools/kvm/.
> >>  >  It's using the same symbols and conventions for 'guest' and
> >>  >  'host' side.
> >>  >
> >>  >  Check out tools/kvm/hw/i8042.c and match it up with
> >>  >  include/linux/serio.h and drivers/input/serio/i8042.c - you can
> >>  >  literally walk from one side to the other and understand how
> >>  >  guest and host are tightly related not just functionality but
> >>  >  also implementation wise.
> >>  >
> >>  >  This is how Qemu should be doing it as well btw., to ease the
> >>  >  debugging of host/guest interaction bugs and to ease development.
> >>
> >>  No. That ties the guest and host interfaces together. [...]
> >
> > Why would it tie the interfaces together? For a guest and host 
> > driver to be written in the same familiar conventions is useful 
> > for debugging and development easier but does not prevent both of 
> > those pieces to implement a precise interface. (Especially since 
> > in the i8042 case the host driver is used with real hardware as 
> > well.)
> 
> The driver is under no requirement to use all of the functionality 
> of the device.  On the other hand, the device emulation has to be 
> complete, or it risks not working with some past or future version 
> of the driver, or with another OS (if you support that).

Sure, and nothing in tools/kvm/hw/i8042.c contradicts that and my 
points still remain.

You can have clean, harmonic code *and* have it work to spec, agreed?

Thanks,

	Ingo