Re: [Xen-users] baremetal to PV troubles (32/64 bit PV hybrid)

[Dylan Martin <dmartin@xxxxxxxxxxxx>]

Thanks!  That answers all my questions!

> On Thu, 12 Jul 2007, Dylan Martin wrote:
> 
> >Thanks for answering!  I have loads more questions...
> >
> >Okay, I think I understand.  I'd use the 64 bit kernel & modules but
> >the 32 bit libs, right?
> >
> >How does the 64 bit kernel know the userland is 32 bit?  Won't it try
> >and find the 64 bit libs and freak out?
> 
> AFAIK, kernels don't find libraries... userspace programs do. The 64 bit 
> kernels provide all the 32 bit system calls (as long as the default option 
> to do that wasn't turned off when the kernel was built).
> 
> >Does it use memory like a 64 bit machine?
> 
> yes, raw memory allocation is a kernel thing.
> 
> >Is there any reason to run a 32 bit domU in a 64 bit dom0?
> 
> yes/no. 32 bit code is generally in more common use and better tested. If 
> you're using precompiled binaries you might not even have an option of 
> running 64 bit code. Or you might simply have a 32 bit install on a 
> physical machine that you want to move to a paravirt on a big machine 
> without rebuilding from scratch and consequently breaking things.
> 
> The one gotcha you will run into with the 32/64 bit hybrid is that some 
> kernel related tools can get upset (iptables being an example, the 
> simplest solution is to build a statically linked binary on a 64 bit 
> machine and copy that across to your 32 bit userspace domU)
> 
> -Tom
> 
> 
> 

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users