WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] "xm mem-max" problem on PAE xenlinux


On 12 Nov 2005, at 03:01, Nakajima, Jun wrote:

kernel BUG at arch/xen/i386/mm/hypervisor.c:381 (xen_create_con
tiguous_region)!'

This may possibly be fixed by changeset 7771 (in staging tree) Patch
attached.

Actually this causes a hang like:

I'd be pretty surprised if that patch caused the hang as it's a pretty
clear cut bug fix.
Are you sure?

Okay, I just remember this nasty issue with menuconfig. If you make SMP
dom0, and go back to UP using memuconfig, the config file gets broken
(CONFIG_APIC stuff). The UP dom0 does not boot anymore.

Sorry, it worked fine.

I'm surprised as the original bug you reported was actually a misuse of 'xm mem-max' (which almost certainly should not be exported to users in its raw form).

You set the Xen memory limit for that domain to less than its current allocation. Then, next time it tried to alloc a pgd, it tried to exchange the underlying mfn for one below 4GB. Xen took the old mfn away from the domain, but then failed the reallocation because the domain already had too much memory!

'xm mem-set' is all that should be exported to users, and the hard limit should be under the control of xend.

 -- Keir


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