Re: [PATCH] Fix save/restore for HVM domains with viridian=1

[Keir Fraser <keir.xen@gmail.com>]

On 25/11/2011 14:58, "Jan Beulich" <JBeulich@suse.com> wrote:

>> xc_domain_save/restore currently pay no attention to HVM_PARAM_VIRIDIAN
>> which
>> results in an HVM domain running a recent version on Windows (post-Vista)
>> locking up on a domain restore due to EOIs (done via a viridian MSR write)
>> being silently dropped.
>> This patch adds an extra save entry for the viridian parameter and also
>> adds code in the viridian kernel module to catch attempted use of viridian
>> functionality when the HVM parameter has not been set.
> 
> Assuming this means the changes to {rd,wr}msr_viridian_regs(), isn't
> this going to needlessly spam the log? I.e. printing this just once (per
> VM) would seem to suffice. Or alternatively I would think that
> HVM_DBG_LOG() would be a better choice here.

It's unlikely to print more than once before the VM wedges. We could go
further and inject #GP, which we ought to be doing anyway.

 -- Keir