Re: Xen 4 rc2: pv domU memory corruption

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Fri, Feb 05, 2010 at 04:42:16PM +1100, Yasir Assam wrote:
> I think I've narrowed down my random crashes to Xen 4.0.0 rc2 causing  
> memory corruption in domUs.
>
> Xen 3.4.2 is ok, and it doesn't seem to matter which domU or dom0 kernel  
> I'm using.
>
> I have two domUs, both PV
>
> * 2.6.32.7 from kernel.org
> * 2.6.18-xen
>
> Everything is 64-bit.
>
> The random segfaults I was getting looked like bad RAM, but memtest86  

These segfaults - were they in dom0 or domU? What CPU do you have?
AMD/Intel?

Did you try to swap the memory modules when you were trying to narrow
this down?

> didn't report any problems. So I ran memtester  
> (http://pyropus.ca/software/memtester/), a userspace mem test app.
>
> When I ran memtester on the dom0 (assigning all available RAM to the  
> dom0) there was no problem. However, when I ran it against either of the  
> domUs, it reported problems with RAM. See memtester output below. The  
> corruption starts at around address 0x02404900.
>
> Uninstalling 4.0 rc2 and installing 3.4.2 got rid of the problem, so it  
> looks like 4.0.0 rc2 could be the problem, rather than any of the  
> kernels or the hardware.

Did you compile 4.0.0-rc2 with debug=y?