Question about x86_compat

Question about x86_compat

[beth kon]

arch_setup_meminit ignores the return code from x86_compat. Is this 
intentional? I see that the message printed in x86_compat is a warning 
if the do_domctl fails, so assume ignoring the return code in 
arch_setup_meminit may be intentional. If so, what does this imply when 
a 32 bit guest attempts to start on a 64 bit machine?

I followed up the call chain from x86_compat (trying to understand its 
intent) and it appears to be a pretty integral part of creating any 
domain, so I assume that XEN_DOMCTL_set_address_size is the call that 
actually specifies to Xen whether a domain is 32 or 64? So if that call 
fails, is the domain just set to be the machine's native size by 
default? But what would that mean for a 32 on 64 guest?

I hope my questions are clear. This area is a little muddy for me. Thanks!

-- 
Elizabeth Kon (Beth)
IBM Linux Technology Center
Open Hypervisor Team
email: eak@us.ibm.com

Re: Question about x86_compat

[Keir Fraser]

It should probably be propagating the error, yes.

 -- Keir

On 4/12/07 02:56, "beth kon" <eak@us.ibm.com> wrote:

> arch_setup_meminit ignores the return code from x86_compat. Is this
> intentional? I see that the message printed in x86_compat is a warning
> if the do_domctl fails, so assume ignoring the return code in
> arch_setup_meminit may be intentional. If so, what does this imply when
> a 32 bit guest attempts to start on a 64 bit machine?
> 
> I followed up the call chain from x86_compat (trying to understand its
> intent) and it appears to be a pretty integral part of creating any
> domain, so I assume that XEN_DOMCTL_set_address_size is the call that
> actually specifies to Xen whether a domain is 32 or 64? So if that call
> fails, is the domain just set to be the machine's native size by
> default? But what would that mean for a 32 on 64 guest?
> 
> I hope my questions are clear. This area is a little muddy for me. Thanks!