Red Hat Bugzilla – Full Text Bug Listing
|Summary:||Change network with netconsole loaded cause kernel panic|
|Product:||Red Hat Enterprise Linux 6||Reporter:||Guohua Ouyang <gouyang>|
|Component:||ovirt-node||Assignee:||Mike Burns <mburns>|
|Status:||CLOSED ERRATA||QA Contact:||Virtualization Bugs <virt-bugs>|
|Version:||6.3||CC:||acathrow, bsarathy, chchen, cshao, fdeutsch, gouyang, hadong, hambrose, huiwa, jboggs, leiwang, mburns, moli, ovirt-maint, sgordon, ycui, yuachen|
|Target Milestone:||rc||Keywords:||TestOnly, ZStream|
|Fixed In Version:||ovirt-node-2.5.0-3.el6||Doc Type:||Bug Fix|
Previously, changing the network configuration of the Red Hat Enterprise Virtualization Hypervisor while netconsole was enabled resulted in a kernel panic ("Kernel panic - not syncing: Watchdog detected hard LOCKUP"). This kernel bug has now been fixed. The hypervisor has been updated to include a later kernel release that does not have this bug. Changing the network configuration of the Hypervisor with netconsole enabled will not result in a kernel panic.
|:||839266 (view as bug list)||Environment:|
|Last Closed:||2013-02-28 11:34:30 EST||Type:||Bug|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
|Bug Depends On:||839266|
Description Guohua Ouyang 2012-05-25 05:25:59 EDT
Description of problem: After the network is up and netconsole is loaded, try change the network, such change network from dhcp to static or configure another nic, kernel panic will happen. on screen can see "Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 6". Version-Release number of selected component (if applicable): rhev-hypervisor6-6.3-20120523.1.el6 How reproducible: 100% Steps to Reproduce: 1. Configure network up. 2. Configure netconsole. 3. Try change network, such change network from dhcp to static or configure another nic. Actual results: Kernel panic happen "Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 1". Expected results: No kernel panic happen. Additional info:
Comment 2 Mike Burns 2012-05-25 07:05:35 EDT
Is this reproducible on RHEL?
Comment 3 Guohua Ouyang 2012-05-25 07:37:44 EDT
Created attachment 586835 [details] kernel_panic screenshot (In reply to comment #2) > Is this reproducible on RHEL? attach the screenshot firstly. test on RHEL63 2.6.32-272.el6: 1. configure network with dhcp 2. loaded netconsole. 3. change network from dhcp to static. 4. service network restart no kernel panic happened.
Comment 4 Mike Burns 2012-05-29 08:22:56 EDT
Any additional info on the panic? Stack trace? core dump? anything?
Comment 5 Fabian Deutsch 2012-05-29 12:06:14 EDT
I could not reproduce this problem with snap 5 using the followign steps: 1. Fresh install 2. Configure network up (dhcp) 3. Configure netconsole (server set to 127.0.0.1) 4. Reconfigure network to static No kernel oops appeared (nothing on the console or dmesg) Can you give any more details, Ouyangguohua?
Comment 8 Guohua Ouyang 2012-05-29 22:11:45 EDT
(In reply to comment #5) > I could not reproduce this problem with snap 5 using the followign steps: > > 1. Fresh install > 2. Configure network up (dhcp) > 3. Configure netconsole (server set to 127.0.0.1) > 4. Reconfigure network to static > > No kernel oops appeared (nothing on the console or dmesg) > > Can you give any more details, Ouyangguohua? if you specify the 127.0.0.1 as the netconsole server, does the service netconsole is loaded? I tried it here the service is not loaded. I think you should specify another valid server to reproduce this bug.
Comment 9 Guohua Ouyang 2012-05-29 22:17:49 EDT
(In reply to comment #4) > Any additional info on the panic? Stack trace? core dump? anything? The only thing can get is on the screen can read "Kernel panic - not syncing: Watchdog detected hard LOCKUP on cpu 6". the screenshot is attaching in comment #3. The screen is hang when pop-up this message, send "CAD" does not work.
Comment 10 Fabian Deutsch 2012-05-30 03:31:16 EDT
(In reply to comment #8) > (In reply to comment #5) > > I could not reproduce this problem with snap 5 using the followign steps: > > > > 1. Fresh install > > 2. Configure network up (dhcp) > > 3. Configure netconsole (server set to 127.0.0.1) > > 4. Reconfigure network to static > > > > No kernel oops appeared (nothing on the console or dmesg) > > > > Can you give any more details, Ouyangguohua? > > if you specify the 127.0.0.1 as the netconsole server, does the service > netconsole is loaded? I tried it here the service is not loaded. Now I was able to reproduce this bug: 1. Fresh install 2. Configure network (dhcp) 3. Configure netconsole (server 10.0.0.1) 4. Reconfigure network to static You should open a second console before running the test so you can look at the trace using dmesg (run dmesg once before you raise the bug to get it into memory) A second thing I noted was that the netconsole service seems not to be active on default: chkconfig --list netconsole only shows off
Comment 13 shaochen 2012-06-07 23:07:06 EDT
Created attachment 590329 [details] netconsole kernel panic
Comment 14 Guohua Ouyang 2012-06-07 23:13:54 EDT
Hi mburns, According to comment #12, restart network service will kernel panic after configure netconsole. This blocks registering to rhevm also if the netconsole is configured. should we bring the bug back to 6.3 or need a technical note? Thanks,
Comment 15 shaochen 2012-06-08 01:09:05 EDT
Test in RHEL6.3-20120606.3 kernel-22.214.171.1248.el6.x86_64 Test result: Restart network service will hung on "Shutting down interface eth0" after configure netconsole. ========================== # cat /etc/issue Red Hat Enterprise Linux Server release 6.3 (Santiago) Kernel \r on an \m # uname -a Linux hp-slot6-eth0.qe.lab.eng.nay.redhat.com 2.6.32-278.el6.x86_64 #1 SMP Fri Jun 1 14:17:12 EDT 2012 x86_64 x86_64 x86_64 GNU/Linux # /etc/init.d/netconsole status netconsole module loaded # /etc/init.d/network restart Shutting down interface br0: [ok] Shutting down interface eth0:
Comment 18 Fabian Deutsch 2012-07-11 08:13:06 EDT
I can also reproduce this on RHEL 6.3 with kernel 2.6.32-279 : 1. Install rhel 2. Configure netconsole to point to 10.42.0.1 3. service netconsole start 4. service network restart And fails to stop the network interfaces (like in bug #816034)
Comment 26 errata-xmlrpc 2013-02-28 11:34:30 EST
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. http://rhn.redhat.com/errata/RHBA-2013-0556.html