Re: Vanilla Linux 64-bit paravirt guest support

[Jeremy Fitzhardinge <jeremy@goop.org>]

Michael Abd-El-Malek wrote:
> Is 64-bit domU support available anywhere at the moment?  For example, 
> what is the status of the git://git.et.redhat.com/xen-pvops-64.git 
> tree?  I pulled that tree and tried building 64-bit Xen domU support 
> (since this tree allows you to configure the kernel with that 
> capability, unlike the vanilla Linux tree).  But compilation failed in 
> enlighten.c because xen_smp_ops isn't defined in x86_64.

Redhat have some patches which they're shipping in Fedora 9.  Once F9 is 
out the door, I'm hoping they'll polish them into an upstreamable form.  
I don't know whether that git tree represents what's in F9, or if that's 
somewhere else; at the very least I'd expect you'd be able to pull the 
patches out of the srpm.

>>> On a related note: is it possible to compile the PV network/block 
>>> drivers for a HVM Linux guest with the newest kernels?  Compilation 
>>> failed and a previous message on the list says that you can't do 
>>> that.  The reason I'd want to do this is to let me run a 64-bit 
>>> recent Linux kernel with PV drivers. 
>>
>> No, we don't support that for the moment, though it would be a useful 
>> thing to have.
>
> Is there a reason this wouldn't work, or is it just "scripting 
> changes" that need to be done? 

In order to simplify the initial upstreaming work, I removed the support 
for pv-in-hvm, since it adds a moderate amount of extra complexity.  
We'd need to put that back in - it shouldn't be too hard, but it hasn't 
been a priority so far.

    J