Re: [RFC PATCH 1/8]: PVH: Basic and preparatory changes

[Mukesh Rathor <mukesh.rathor@oracle.com>]

On Thu, 13 Sep 2012 07:00:07 +0100
Ian Campbell <Ian.Campbell@citrix.com> wrote:

> On Wed, 2012-09-12 at 20:32 +0100, Mukesh Rathor wrote:
> > On Wed, 12 Sep 2012 19:26:20 +0100
> > Ian Campbell <Ian.Campbell@citrix.com> wrote:
> > 
> > > On Wed, 2012-09-12 at 19:02 +0100, Mukesh Rathor wrote:
> Callback vector is XENFEAT_hvm_callback_vector, I think.
> 
> A PV kernel is required to announce the features which it supports via
> the elf notes (defined in xen-head.S).
> 
> It would be a bug for the toolstack to enable PVH mode for a kernel
> which did not claim to support the required featureset.
> 
> The aim should be that the user should not normally need to specify
> pvh one way or the other, imagine a use case where pygrub is used to
> boot both old and new kernels using it.
> 
> The toolstack (or the dom0 builder) can make the determination whether
> to enable this mode itself itself based on the notes (although it is
> always handy to have an override to force things for debug).

Hmmm... So you are suggesting that if hardware and xen supports it, then
PV should just boot in PVH mode and user has no way to override it. I
don't know if that's a good idea in the short term, perhaps in the long
term. Let me discuss with folks here a bit.

thanks,
Mukesh