Norbert Zeh [2011.04.11 2102 -0300]:
Divan Santana [2011.04.11 2132 +0200]:
On Monday 11 April 2011 20:58:40 Norbert Zeh wrote:
I just upgraded to the latest kernel. The /etc/rc.d/mdadm script, which starts mdadm in monitor mode, reports a segmentation fault in mdadm --monitor --oneshot --scan.
I also tried to manually start, e.g., mdadm --monitor /dev/md0, and get a segmentation fault there, too.
Since this did not happen before the kernel upgrade and mdadm interacts rather closely with the kernel, I suspect that some change in the latest kernel is to blame for this.
Did anybody else run into the same problem?
Where would I start debugging it?
Downgrade to 2.6.37.5/6 and confirm it's the kernel. Then search for a bug, join the bug report, or file one.
I had this on my to-do list already, but I appreciate the suggestion. Now, the good news is: it's not the kernel, as the same thing happens with the kernel I was running previously: 2.6.37.5.
The bad news: it still happens, and I think I know the culprit. mdadm was upgraded along with my kernel upgrade. So occam's razor suggests the new version of mdadm itself is to blame for the segfault. Unfortunately, while I diligently keep old versions of my kernel package, I don't have the previous version of mdadm lying around to investigate this further. Any suggestions?
And things got even stranger just now, with a silver lining. The version of mdadm found in [core] is 3.2.1. ABS, on the other hand, still has the old version (3.1.5). Isn't ABS supposed to be the official source tree for the official repos? Maybe I misunderstand the relationship between ABS and the repos. In any case, given that ABS still had the old version, I was able to rebuild the old version of mdadm and downgrade. Voila, it works, with the newest kernel. So the culprit is the new mdadm version. I guess it's time to report the bug upstream and, for now, stick to the old version of mdadm. Cheers, Norbert