public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: Gleb Natapov <gleb@redhat.com>
To: Stefan Pietsch <stefan.pietsch@lsexperts.de>
Cc: kvm@vger.kernel.org
Subject: Re: kernel 3.10.1 - "NMI received for unknown reason"
Date: Sun, 25 Aug 2013 14:45:29 +0300	[thread overview]
Message-ID: <20130825114529.GO8218@redhat.com> (raw)
In-Reply-To: <52053F85.1070705@sp.consulting.lsexperts.de>

On Fri, Aug 09, 2013 at 09:14:13PM +0200, Stefan Pietsch wrote:
> On 04.08.2013 14:44, Gleb Natapov wrote:
> > On Fri, Aug 02, 2013 at 08:24:38AM +0200, Stefan Pietsch wrote:
> >> On 31.07.2013 11:20, Gleb Natapov wrote:
> >>> On Wed, Jul 31, 2013 at 11:10:01AM +0200, Stefan Pietsch wrote:
> >>>> On 30.07.2013 07:31, Gleb Natapov wrote:
> >>>>
> >>>>> What happen if you run perf on your host (perf record -a)?
> >>>>> Do you see same NMI messages?
> >>>>
> >>>> It seems that "perf record -a" triggers some delayed NMI messages.
> >>>> They appear about 20 or 30 minutes after the command. This seems strange.
> >>> Definitely strange. KVM guest is not running in parallel, correct? 20, 30
> >>> minutes after perf stopped running or it is running all of the time?
> >>
> >> No, the KVM guest ist not running in parallel. But I'm not able to
> >> clearly reproduce the NMI messages with "perf record".
> >> I start "perf record -a" and after some minutes I stop the recording.
> >>
> >> After that it seems NMI messages appear within a random period of time.
> >> So, I cannot tell what triggers the messages.
> > When you run KVM with coreduo cpu model it emulates PMU which basically
> > make is perf front end. If you can reproduce the messages with perf too
> > it probably means that the problem is not in the KVM itself. If you
> > disabled NMI watchdog in the guest the messages may go away.
> > Can you send your guest's dmesg when you boot it with coreduo mode?
> 
> 
> The NMI messages appear in the host only. The guest runs as usual.
> 
> 
I understand that. But enabling guest nmi watchdog is what makes KVM to
use perf subsystem and likely causes this host messages. Try do disable
nmi watchdog in a guest and see what happens.

--
			Gleb.

  reply	other threads:[~2013-08-25 11:45 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-26 18:25 kernel 3.10.1 - "NMI received for unknown reason" Stefan Pietsch
2013-07-26 18:39 ` Gleb Natapov
2013-07-29  9:09   ` Stefan Pietsch
2013-07-29  9:16     ` Gleb Natapov
2013-07-29 20:50       ` Stefan Pietsch
2013-07-30  5:31         ` Gleb Natapov
2013-07-31  9:10           ` Stefan Pietsch
2013-07-31  9:20             ` Gleb Natapov
2013-08-02  6:24               ` Stefan Pietsch
2013-08-04 12:44                 ` Gleb Natapov
2013-08-09 19:14                   ` Stefan Pietsch
2013-08-25 11:45                     ` Gleb Natapov [this message]
2013-08-26 21:48                       ` Stefan Pietsch

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20130825114529.GO8218@redhat.com \
    --to=gleb@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=stefan.pietsch@lsexperts.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox