[DRBD-user] Kernel panic from drdbadm on CentOS 6

[Dominik Epple]

Hi list,

we are facing kernel panics with CentOS 6 (RHEL 6 compatible) with kernel version 2.6.32-71.29.1.el6.x86_64, drbd version 8.3.11 built from sources.

Some days ago David Coulson reported the same problem in a thread called "DRBD trace with RHEL6.1 upgrade". The last mail in the thread (Wed Aug 3 16:31:56 CEST 2011) has a screenshot with the call trace (http://i.imgur.com/cSOzV.png). Since I have no (easy) means of taking a screenshot of the call trace from my machine, I cannot give one here, but it is the very same problem with Process drbdadm and vfs_ioctl in the call trace, etc.

I cannot say, unfortunately, how to reproduce the panic. I was unable to found out a single event which triggers it reproducibly. But it seems that it is necessary that drbd runs under a cluster management system (pacemaker/corosync in my case).

Actions that can trigger those panics include:
   * Starting the pacemaker drbd resource via "crm resource start <resourcename>"
   * Restarting the cluster management system via "service corosync restart"
   * Doing a "ifdown eth0; ifup eth0" for the interface drbd is run over

Since the other thread has no answer to this problem, I ask here again: Where does this panic come from? Is there a solution, patch, or workaround known?

Thanks and regards
Dominik Epple