Re: [Xen-devel] Hypervisor error messages after xl block-detach with linux 3.18-rc5

[Juergen Gross <jgross@xxxxxxxx>]

On 11/24/2014 04:09 PM, Juergen Gross wrote:
> On 11/24/2014 11:59 AM, Juergen Gross wrote:
> > On 11/24/2014 11:20 AM, Jan Beulich wrote:
> > > > > > On 24.11.14 at 10:55, <JGross@xxxxxxxx> wrote:
> > > > - Sometimes I see only NMI watchdog messages, looking into hanging cpu
> > > >     state via xen debug keys I can see the cpu(s) in question are
> > > > spinning
> > > >     in _raw_spin_lock():
> > > >     __handle_mm_fault()->__pte_alloc()->pmd_lock()->_raw_spin_lock()
> > > >     The hanging cpus were executing some random user processes (cron,
> > > >     bash, xargs), cr2 contained user addresses.
> > > Is this perhaps what
> > > http://lists.xenproject.org/archives/html/xen-devel/2014-11/msg02135.html
> > >
> > > appears to be about?
> > Hmm, I'm not sure.
> >
> > I'll try a 3.17 kernel to verify.
> Still seeing the issue, but less frequent. OTOH I just found in above
> thread in lkml that 3.17 is showing that issue, too. :-(
>
> I'll try to setup a pv-variant of Linus' patch and test it...
First test seems to be okay, no immediate NMI message...

Any idea why the block-attach/detach would trigger this problem so
easily? I can see the dependency on the high cpu count, but fail to do
so for the xl actions.


Juergen


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel