[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xen-devel] Xen 3.2.1-rc1: FATAL PAGE FAULT


  • To: "Christopher S. Aker" <caker@xxxxxxxxxxxx>, xen devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
  • From: Keir Fraser <keir.fraser@xxxxxxxxxxxxx>
  • Date: Thu, 03 Apr 2008 16:55:29 +0100
  • Delivery-date: Thu, 03 Apr 2008 08:57:54 -0700
  • List-id: Xen developer discussion <xen-devel.lists.xensource.com>
  • Thread-index: AciVoyOgYfnoIwGWEd2UmgAX8io7RQ==
  • Thread-topic: [Xen-devel] Xen 3.2.1-rc1: FATAL PAGE FAULT

On 3/4/08 15:04, "Christopher S. Aker" <caker@xxxxxxxxxxxx> wrote:

>>> Maybe the symbols would help just a little bit?  In any case, here are
>>> the files:
>>> 
>>> http://theshore.net/~caker/xen/BUGfatal_page_fault/
>> 
>> I will take a look. It might help narrow down the possibilities a bit.
>> 

My analysis is that the hypervisor crashed because one of the entries in a
dying guest's third-level page directory has the present bit (bit 0) set,
yet the physical address mapped by that entry is 0xb72dedde51000. That is a
rather large and obviously bogus number! It causes us to access way off the
end of an array indexed by physical address, resulting in a fatal page
fault.

Obviously the question is: Where did the bogus address come from?

That's going to be rather hard to answer without finding a more reliable
repro of the bug, and then adding some hypervisor tracing.

 -- Keir



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


 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.