Re: [Xen-devel] Re: [Qemu-devel] [PATCH V10 02/15] xen: Make xen build only on x86 target.

[Stefano Stabellini]

On Fri, 11 Mar 2011, Alexander Graf wrote:
> 
> On 24.02.2011, at 18:59, Anthony Liguori wrote:
> 
> > On 02/24/2011 11:46 AM, Jan Kiszka wrote:
> >> On 2011-02-24 18:27, Anthony Liguori wrote:
> >>   
> >>> On 02/24/2011 10:25 AM, Anthony PERARD wrote:
> >>>     
> >>>> On Thu, Feb 24, 2011 at 16:11, Anthony Liguori<address@hidden>   wrote:
> >>>> 
> >>>>       
> >>>>> Is this really necessary?  The advantage to building globally is that it
> >>>>> keeps the code from getting unnecessary i386-isms.
> >>>>> 
> >>>>>         
> >>>> Nop, is not necessary, I add this patch after this mail:
> >>>> http://lists.nongnu.org/archive/html/qemu-devel/2010-12/msg00044.html
> >>>> 
> >>>>       
> >>> Alex, do you feel strongly here?
> >>>     
> >> I'm not Alex, but I brought this issue up:
> >> 
> >> Either build xen bits once for all archs or restrict it to the only
> >> foreseeable arch with support in qemu. But please don't built it for
> >> each and every target separately.
> >>   
> > 
> > Oh yes, I misunderstood.  I thought we had previously built it for all 
> > architectures.  Yes, we should only build it once.
> 
> There's really no point in building it for anything but x86. Xen has never 
> had been broadly used in PV mode on non-x86. Not sure ports even exist.
> 

There is an ia64 port available, but restricting xen to x86 makes sense
at least for the moment.


BTW qemu is mainly used in HVM mode on xen, but considering that cpu
emulation is not needed, qemu x86 would probably work for the ia64 case
too: this is how qemu-xen is used on ia64 at the moment, even though in
the qemu-xen case xen is not an accelerator but a new target with a set
of hardware devices very similar to x86.