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I have a brand new CentOS 6.5 install with two (mounted to /mnt/data) 1tb Western Digital Black drives in raid 1 with mdadm, configured via the installer. Unfortunately every now and again the entire system kernel panics with a trace similar to below:

Kernel Panic

Any tips on diagnosing or fixing this? Much appreciated!

EDIT: It appears this happened around the same time as a raid data check occured: EDIT 2: The last two crashes have happened at just past 1am Sunday, same time data check occurs.

Mar 23 01:00:02 beta kernel: md: data-check of RAID array md0
Mar 23 01:00:02 beta kernel: md: minimum _guaranteed_  speed: 1000 KB/sec/disk.
Mar 23 01:00:02 beta kernel: md: using maximum available idle IO bandwidth (but not more than 200000 KB/sec) for data-check.
Mar 23 01:00:02 beta kernel: md: using 128k window, over a total of 976629568k.


    Personalities : [raid1] 
md0 : active raid1 sdc1[1] sdb1[0]
      976629568 blocks super 1.1 [2/2] [UU]
      bitmap: 0/8 pages [0KB], 65536KB chunk

unused devices: <none>

mdadm -D

        Version : 1.1
  Creation Time : Fri Mar  7 16:07:17 2014
     Raid Level : raid1
     Array Size : 976629568 (931.39 GiB 1000.07 GB)
  Used Dev Size : 976629568 (931.39 GiB 1000.07 GB)
   Raid Devices : 2
  Total Devices : 2
    Persistence : Superblock is persistent

  Intent Bitmap : Internal

    Update Time : Sun Mar 23 03:36:59 2014
          State : active 
 Active Devices : 2
Working Devices : 2
 Failed Devices : 0
  Spare Devices : 0

           Name :  (local to host
           UUID : 89a86538:f6162473:d5e0524c:b80566d6
         Events : 1728

    Number   Major   Minor   RaidDevice State
       0       8       17        0      active sync   /dev/sdb1
       1       8       33        1      active sync   /dev/sdc1

EDIT 3: Different crash, occurred during a forced resync / check, also memtest passed 4 passes just fine:

EDIT 4: Even dd is causing crashes:

EDIT 5: The SSD survives the dd torture test, guess that means I'm gonna try the drives without raid.

share|improve this question
I'm just trying to get my head around how the SSD relates, could you cut-and-paste the output of cat /proc/mdstat into your question? – MadHatter Mar 23 '14 at 9:42
The SSD doesn't relate. I have amended the question with the mdstat output as well as some info regarding the potential cause – md_5 Mar 23 '14 at 10:44
Yup, the last two crashes have been at just past 1am Sunday, the same time the data check is running. – md_5 Mar 23 '14 at 10:48
Try to get the first crash after a system boot. These are not the first crash and may not be indicative of the actual problem. You ought to find it in the system log /var/log/messages. Try searching the log for Not tainted. – Michael Hampton Mar 23 '14 at 14:17
The only other stuff is this: /var/log/messages-20140323:Mar 23 03:37:07 beta kernel: WARNING: at drivers/pci/dmar.c:588 warn_invalid_dmar+0x7a/0x90() (Tainted: G I--------------- ) /var/log/messages-20140323:Mar 23 03:37:07 beta kernel: Pid: 1, comm: swapper Tainted: G I--------------- 2.6.32-431.5.1.el6.x86_64 #1 Which happens right at the start of system boot indicating the bios reported DMAR at address 0. This is fine and a normal bug with Linux on all Gigabyte mobos, hasn't affected stability on any other of my systems. – md_5 Mar 23 '14 at 20:12

This might give an indication of the disk hardware state:

[root@ninja ~]$ /etc/rc.d/init.d/smartd start

[root@ninja ~]$ smartctl --all /dev/sdc | grep 'health'
SMART overall-health self-assessment test result: PASSED

[root@ninja ~]$ smartctl --all /dev/sdb | grep 'health'
SMART overall-health self-assessment test result: PASSED
share|improve this answer
Both drives pass, they are fine. – md_5 Mar 27 '14 at 9:24
Or, indeed, smartctl -H /dev/sda. – MadHatter Mar 27 '14 at 9:31
Have you tried other kernels, for e.g. kernel-2.6.32-358.18.1/2.6.32-431.11.2.el6? – ALex_hha Mar 27 '14 at 11:35

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