From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dor Laor Subject: Re: 2.6.23.1-rt4 and kvm 48 Date: Tue, 06 Nov 2007 10:12:56 +0200 Message-ID: <47302208.2090301@qumranet.com> References: <9c21eeae0710290709x527cf4fcq52bb410907ff496@mail.gmail.com> <47299C43.1070703@qumranet.com> <472F7CA7.8060707@osadl.org> <9c21eeae0711052122y483b06d8ycbcfbfb95fb36663@mail.gmail.com> Reply-To: dor.laor-atKUWr5tajBWk0Htik3J/w@public.gmane.org Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============2056092582==" Cc: kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org, Carsten Emde To: David Brown Return-path: In-Reply-To: <9c21eeae0711052122y483b06d8ycbcfbfb95fb36663-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: kvm-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: kvm.vger.kernel.org This is a multi-part message in MIME format. --===============2056092582== Content-Type: multipart/alternative; boundary="------------040103040700060202030308" This is a multi-part message in MIME format. --------------040103040700060202030308 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit David Brown wrote: >>> I tried to recreate your problem using 2.6.23-1 and latest rt patch (rt5). >>> The problem is that the kernel is not stable at all, I can't even >>> compile the code over vnc - >>> my connection is constantly lost. So it might not be kvm problem? >>> Can you try is with -no-kvm and see if it's working - then its just a >>> regular userspace process. >>> Anyway if all other things are stable on your end, can you send us >>> dmesg/strace outputs? >>> >> Thanks, Dor, for offering help. >> >> The most recent RT-Preempt patch (2.6.23.1-rt5) still has an SMP issue >> which need to be sorted out first. >> >> When a working RT-Preempt patch is available, I will be glad to send >> dmesg outputs. We may then share our activities to create the next >> "Latest stable" RT-Preempt kernel that includes kvm support. >> > > Wow, that smp issue may be a problem I've got a Intel Core 2 cpu with > just 2 cores. > > but I've not seen a dump like this in a while (lustre?). > > I've updated to 2.6.23-rt5 and kvm-50 and I got this dump.... > > [ 254.639143] audit(1194322621.379:3): dev=tap0 prom=256 old_prom=0 auid=429496 > 7295 > [ 254.647231] br0: port 2(tap0) entering learning state > [ 255.988741] IRQ-23[942]: segfault at 0000000000000000 rip 00002ac.994386] Cal > l Trace: > <4>[ 255.994387] <3>[ 255.998090] BUG: scheduling while atomic: swapper/0x0 2 > 56.002986] Call Trace: > [ 256.002986] > [ 256.00ad! > <4>[ 256.007635] > <4>[ 256.007635] Call Trace:G: scheduling while atomic: swapper/0x00000003/0, C > PU#all Trace: > [ 256.016955] > [ 256.016956] bad: sched1615] > <4>[ 256.021615] Call Trace: > [ 256.021616]e atomic: swapper/0x00000003/0, CPU#1 > [ 256.026276] .030935] > [ 256.030936] bad: scheduling from the idl35595] Call Trace: > [ 256.035595] > [ 256.035596] B0000003/0, CPU#1 > <4>[ 256.040256] > > This loops forever basically... > I'm really confused about this one. I've got the full minicom.cap file > from the session that produced this its attached zipped up. > > If you'd like any other information I'd be glad to post it. > > - David Brown > If the rt patch is not smp stable you can boot with single cpu and run kvm there. Maybe just pinning the guest to specific cpu will help although I had troubles with X too. Dor. --------------040103040700060202030308 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit David Brown wrote: 
I tried to recreate your problem using 2.6.23-1 and latest rt patch (rt5).
The problem is that the kernel is not stable at all, I can't even
compile the code over vnc -
my connection is constantly lost. So it might not be kvm problem?
Can you try is with -no-kvm and see if it's working - then its just a
regular userspace process.
Anyway if all other things are stable on your end, can you send us
dmesg/strace outputs?
      
Thanks, Dor, for offering help.

The most recent RT-Preempt patch (2.6.23.1-rt5) still has an SMP issue
which need to be sorted out first.

When a working RT-Preempt patch is available, I will be glad to send
dmesg outputs. We may then share our activities to create the next
"Latest stable" RT-Preempt kernel that includes kvm support.
    

Wow, that smp issue may be a problem I've got a Intel Core 2 cpu with
just 2 cores.

but I've not seen a dump like this in a while (lustre?).

I've updated to 2.6.23-rt5 and kvm-50 and I got this dump....

[  254.639143] audit(1194322621.379:3): dev=tap0 prom=256 old_prom=0 auid=429496
7295
[  254.647231] br0: port 2(tap0) entering learning state
[  255.988741] IRQ-23[942]: segfault at 0000000000000000 rip 00002ac.994386] Cal
l Trace:
<4>[  255.994387] <3>[  255.998090] BUG: scheduling while atomic: swapper/0x0  2
56.002986] Call Trace:
[  256.002986]
[  256.00ad!
<4>[  256.007635]
<4>[  256.007635] Call Trace:G: scheduling while atomic: swapper/0x00000003/0, C
PU#all Trace:
[  256.016955]
[  256.016956] bad: sched1615]
<4>[  256.021615] Call Trace:
[  256.021616]e atomic: swapper/0x00000003/0, CPU#1
[  256.026276] .030935]
[  256.030936] bad: scheduling from the idl35595] Call Trace:
[  256.035595]
[  256.035596] B0000003/0, CPU#1
<4>[  256.040256]

This loops forever basically...
I'm really confused about this one. I've got the full minicom.cap file
from the session that produced this its attached zipped up.

If you'd like any other information I'd be glad to post it.

- David Brown
If the rt patch is not smp stable you can boot with single cpu and run kvm there.
Maybe just pinning the guest to specific cpu will help although I had troubles with X too.
Dor.
--------------040103040700060202030308-- --===============2056092582== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ --===============2056092582== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ kvm-devel mailing list kvm-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org https://lists.sourceforge.net/lists/listinfo/kvm-devel --===============2056092582==--