Re: [Xen-devel] dom0 boot failure with 256G

[Keir Fraser <keir.fraser@xxxxxxxxxxxxx>]

On 5/6/08 05:00, "Ian Pratt" <Ian.Pratt@xxxxxxxxxxxxx> wrote:

>>     I've been intensely debugging a dom0 crash right at boot in
>>     pagetable_init() with 256G. We are running 64bit hyp with 32bit
>> dom0.
>>     This on xen 3.1.3, which seems to have fixes from changeset 16548.
> 
> 256GB is more than a 32b dom0 can handle. Presumably it works if you set
> dom0_mem= to something smaller?
> 
> We should probably make the clipping of dom0 memory to something like
> 64GB automatic.

Xen ought to have crashed during dom0 build in that case, being unable to
allocate enough memory of the restricted address width supported by the 32b
dom0 guest. I agree that dom0_mem should be automatically intelligently
clamped. Currently nr_pages is clamped to UINT_MAX (!) for a 32b dom0, which
is still rather a big number.

I'll have to sketch out exactly what that physaddr_bitsize computation is
doing and see if I can make sense of it...

 -- Keir



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