Re: Xen 4.1 regression - can't boot on 1TB anymore (Xen 4.0 could).

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

On Wed, Mar 28, 2012 at 01:59:07PM +0100, Jan Beulich wrote:
> >>> On 27.03.12 at 20:13, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> wrote:
> > With Xen 4.0 we could boot up dom0 with 1TB of memory. But with
> > Xen 4.1 that is no longer the case. Any ideas of what might be the culprit?
> > 
> > Please see attached logs.
> 
> Is this with the same kernel? I suspect not, in particular because of

No, it is a pvops kernel (the older was a 2.6.32 classic one).
> 
> (XEN)  Phys-Mach map: ffffea0000000000->ffffea007e5acc80
> 
> vs
> 
> (XEN) Dom0 memory clipped to 130846720 pages
> 
> (the former suggesting a kernel making use of XEN_ELFNOTE_INIT_P2M,
> i.e. a forward ported one based on ours, the latter suggesting one
> that doesn't, e.g. pv-ops). If booting fails completely, I'd suppose
> the clipping calculation might be off by a few pages. Does output look
> the same with "sync_console"? If so, does "watchdog" allow you to
> get a stack trace and register dump of where execution hangs?

Ok, will try those out.
> 
> I also suppose that the second kernel boots fine when you pass
> dom0_mem= with a value below 400G.

It does indeed. Thought the value that was used was a more conservative
of 4G.
> 
> Jan