Note: This bug is displayed in read-only format because
the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.
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.
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:
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.
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?
(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.
(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.
(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
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,
Test in RHEL6.3-20120606.3
kernel-2.6.32.278.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:
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)
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