Re: Dom0 PAE panic when starting xend

[Christoph Egger <Christoph_Egger%gmx.de@localhost>]

On Tuesday 10 March 2009 18:42:21 Manuel Bouyer wrote:
> On Tue, Mar 10, 2009 at 05:59:47PM +0100, Christoph Egger wrote:
> > > [1] http://www.netbsd.org/~jym/xenevt.c.diff
> >
> > The output with this patch is:
> >
> > store_mfn: MFN 1050807 PFN 1431654400
> > store_mfn: MFN 1050807 PFN 1431654400
> > (XEN) mm.c:1784:d0 Error pfn 55555: rd=ff2b4100, od=00000000,
> > caf=00000000, taf=00000000
> > (XEN) mm.c:712:d0 Error getting mfn 55555 (pfn 55555555) from L1 entry
> > 0000000055555067 for dom0
> > xpq_flush_queue: 1 entries
> > 0x000000010211d608: 0x0000000055555067
> > panic: HYPERVISOR_mmu_update failed
>
> Is it really called twice ? If so why is it working the first time and
> not the second ?
> I also notice 1431654400 is 0x55555000. Is it really what
> xenbus_probe_init() did allocate ?

Just checked with a debug printf. The answer is yes.

> This one will overflow a << PAGE_SHIFT. Also xen_start_info.store_mfn is
> 32bit on i386 (even PAE) so we have to cast it before << PAGE_SHIFT.
> Does the attached patch (in place or jym's one) help ?

Christoph