Re: Xen dom0 linux kernel 3.1 boot failure ptwr_emulate: could not get_page_from_l1e

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

On Mon, Oct 31, 2011 at 01:17:09PM +0000, Tobias Heinlein wrote:
> Hi,
> 
> 2013pfoley <2013pfoley <at> tjhsst.edu> writes:
> > [..]
> >
> >  [    0.000000] last_pfn = 0x63b5ef max_arch_pfn = 0x400000000
> >  [    0.000000] last_pfn = 0xdf62d max_arch_pfn = 0x400000000
> >  [    0.000000] found SMP MP-table at [ffff8800000f4f80] f4f80
> >  (XEN) mm.c:945:d0 Error getting mfn 100 (pfn 5555555555555555) from L1 
> >  entry 8000000000100461 for l1e_owner=0, pg_owner=0
> >  (XEN) mm.c:5046:d0 ptwr_emulate: could not get_page_from_l1e()
> >  [    0.000000] BUG: unable to handle kernel NULL pointer dereference at 
> >           (null)
> >  [    0.000000] IP: [<ffffffff81008a5a>] xen_set_pte+0x3a/0x1f0
> >  [    0.000000] PGD 0
> >  [    0.000000] Oops: 0003 [#1] SMP
> >  [    0.000000] CPU 0
> >  [    0.000000] Modules linked in:
> >  [    0.000000]
> >  [    0.000000] Pid: 0, comm: swapper Not tainted 3.1.0 #4 HP ProLiant 
> >  DL380 G6
> 
> I get the exact same error here. Reading from your output, it seems we have the
> same hardware; I have this problem on a HP ProLiant DL380 G6, too. 
> 
> After a wild hint from a guy on ##xen to play around with the BIOS settings, I
> was able to narrow down the problem to a setting called "MPS Table Mode". It is
> set to "Full Table APIC" by default (with which the crash occurs), but when it's
> set to "Disabled" Xen boots the kernel just fine.
> 
> FWIW, the help text of the setting is: "Multi Processor Specification (MPS)
> Table / APIC Setting is used for interrupt routing. Certain unsupported
> operating systems may require setting the MPS Table Mode to APIC Disabled."

Oh nice. What does you /proc/interrupts look like compared to baremetal?

> 
> (BTW, the kernel itself boots fine without Xen. So I'm not sure if this belongs
> to the LKML at all.)

It does not. But CC-ing xen-devel here for further tracking.