Bug 212826 - xen_net: Memory squeeze in netback driver.
Summary: xen_net: Memory squeeze in netback driver.
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Fedora
Classification: Fedora
Component: kernel-xen
Version: 6
Hardware: x86_64
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Herbert Xu
QA Contact: Virtualization Bugs
URL:
Whiteboard:
Depends On:
Blocks: 213430
TreeView+ depends on / blocked
 
Reported: 2006-10-29 12:53 UTC by Heiko Jakob
Modified: 2009-12-14 20:38 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2008-02-26 23:35:43 UTC
Type: ---
Embargoed:


Attachments (Terms of Use)

Description Heiko Jakob 2006-10-29 12:53:47 UTC
Description of problem:

Networking between all domains fails. The following message is flodding all
domains ( dmo0 + domU ) /var/log/messages : "xen_net: Memory squeeze in netback
driver."

Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1. make network traffic between domU and dom0. For example:
root@xendom0# ping xendomU1

  
Actual results:
/var/log/messages get's flooded on dom0 and on all domU ( even those not on the
same virtual-network (bridge) )


Expected results:
Should work :-)

Additional info:

Comment 1 Stephen Tweedie 2006-10-30 11:32:24 UTC
When do these occur?  On boot?  On domain creation?  Under load?  What
networking configuration are you using?


Comment 2 Heiko Jakob 2006-10-30 21:51:08 UTC
They occure when the first few bytes are going over any bridge.
It doesn't matter from which system the data is comming from or going to as long
at least one of them is on xenbr(0-2), which actually means any domain in my
configuration.

The System has 2 phys. networkinterfaces. Each of them is connected to a bridge.
One bridge for the LAN, another for the internet connection. There is also a
pure virtual bridge for the DMZ.

dom0         domU*(multiple internal systems)
 |             |
xenbr0-eth0 (LAN)
 |            
domU(router/fw)     
 |
xenbr1 (DMZ) - domU*(multiple DMZ systems) 
 |
domU(router/fw)
 |
xenbr2-eth1 (internet)
 |
internet

Comment 3 Heiko Jakob 2006-11-01 10:21:41 UTC
Problem solved.
domU running kernel-xenU-2.6.17-1.2174_FC5 breaks networking with dom0
2.6.18-1.2798.fc6xen. 

When all domUs are running 2.6.17-1.2187_FC5xenU everything works fine. Booting
one with kernel-xenU-2.6.17-1.2174_FC5 breaks everything on all xenbr*. After
stopping the "bad" domU everything resumed working.




Comment 4 Stephen Tweedie 2006-11-01 13:10:56 UTC
So when you have one 2174 kernel running, all other domains fail all the time? 
That one domain breaks all the others?  Or is only the 2174 domain itself broken?

Comment 5 Heiko Jakob 2006-11-01 14:00:37 UTC
Yes. All interfaces connected to a xenbridge become unavailable. Even those
which are not on the same xenbridge. The only devices that are still working are
the physical devices on dom0. 

I've removed all domains from autostart and started each domU manually.

First i've started my firewall/router domU which seperates the LAN from the DMZ
and pinged it from dom0 and it worked. Then started the outer firewall/router
domU and it was pingable too. After starting a domU connected to (xenbr0) with
the 2174 kernel the pings to my outer router stopped. After shutting it down the
pings made theire way again. Since it was the only domU still on 2174 i've
upgraded it and tried again and everything worked. Since i have the old kernel
still installed it's very easy form me to reproduce. If you want any traces
please let me know.

Regards Heiko





Comment 6 Herbert Xu 2006-11-06 18:48:27 UTC
What do you see if you run a tcpdump on the interface of the 2174 domU (both in
the domU and in dom0)?

Comment 7 Red Hat Bugzilla 2007-07-25 01:34:22 UTC
change QA contact

Comment 8 Chris Lalancette 2008-02-26 23:35:43 UTC
This report targets FC6, which is now end-of-life.

Please re-test against Fedora 7 or later, and if the issue persists, open a new bug.

Thanks



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