Bug 1393206

Summary: Segmentation fault for RAID5 three volume array when third disk is missing
Product: Red Hat Enterprise Linux 6 Reporter: Zhang Xiaotian <xiaotzha>
Component: dmraidAssignee: Heinz Mauelshagen <heinzm>
Status: CLOSED WONTFIX QA Contact: Zhang Yi <yizhan>
Severity: high Docs Contact:
Priority: high    
Version: 6.8CC: agk, heinzm, jbrassow, msnitzer, prajnoha, yizhan, zkabelac
Target Milestone: rcFlags: heinzm: needinfo+
Target Release: ---   
Hardware: x86_64   
OS: Linux   
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Last Closed: 2017-12-06 10:43:03 UTC Type: Bug
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Zhang Xiaotian 2016-11-09 05:54:20 UTC
Description of problem:
Segmentation fault when starting rebuild on 3 volume RAID5.
After issuing command: dmraid -R, segmentation error shows up.

Version-Release number of selected component (if applicable):
RHEL6.8 with kernel-2.6.32-642.el6.x86_64

# rpm -qa dmraid*
dmraid-events-1.0.0.rc16-11.el6.x86_64
dmraid-1.0.0.rc16-11.el6.x86_64

How reproducible:
Always

Steps to Reproduce:
1.echo y |  dmraid  -f  isw -C Raid5 --type 5 --disk "/dev/sdb /dev/sdc /dev/sdd"
2.reboot PC - remove third disk from raid
3.dmraid -R isw_defiaifai_Raid5 /dev/sdd
ERROR: isw: wrong number of devices in RAID set "isw_defiaifai_Raid5" [2/3] on /dev/sdb
ERROR: isw: wrong number of devices in RAID set "isw_defiaifai_Raid5" [2/3] on /dev/sdc
Segmentation fault (core dumped)

Actual results:
Segmentation fault

Expected results:
Rebuilding starts and finishes positively.

Additional info:

Comment 1 Zhang Xiaotian 2016-11-09 06:38:03 UTC
I also encountered this problem on RAID1,  with the steps below:

# dmraid  -f  isw -C Raid1 --type 1 --disk "/dev/sdb /dev/sdc"

# dmraid -tay
isw_bijaajbejg_Raid1: 0 1953515520 mirror core 2 131072 nosync 2 /dev/sdb 0 /dev/sdc 0 1 handle_errors

# dmraid -r
/dev/sdb: isw, "isw_bijaajbejg", GROUP, ok, 1953525166 sectors, data@ 0
/dev/sdc: isw, "isw_bijaajbejg", GROUP, ok, 1953525166 sectors, data@ 0

# dmraid -s
*** Group superset isw_bijaajbejg
--> Subset
name   : isw_bijaajbejg_Raid1
size   : 1953515520
stride : 128
type   : mirror
status : ok
subsets: 0
devs   : 2
spares : 0
# dmraid -ay
RAID set "isw_bijaajbejg_Raid1" was activated
device "isw_bijaajbejg_Raid1" is now registered with dmeventd for monitoring
# dmraid -an
ERROR: device "isw_bijaajbejg_Raid1" is not currently being monitored
# dmraid -E -r /dev/sdc
Do you really want to erase "isw" ondisk metadata on /dev/sdc ? [y/n] :y

# dmraid -s
ERROR: isw: wrong number of devices in RAID set "isw_bijaajbejg_Raid1" [1/2] on /dev/sdb
*** Group superset isw_bijaajbejg
--> *Inconsistent* Subset
name   : isw_bijaajbejg_Raid1
size   : 1953515520
stride : 128
type   : mirror
status : inconsistent
subsets: 0
devs   : 1
spares : 0

# dmraid -R isw_bijaajbejg_Raid1 /dev/sdc
ERROR: isw: wrong number of devices in RAID set "isw_bijaajbejg_Raid1" [1/2] on /dev/sdb
Segmentation fault (core dumped)

Comment 2 Heinz Mauelshagen 2017-10-04 13:32:46 UTC
We recommend mdadm to run isw (Intel Matrix RAID) arrays from RHEL6 on instead of dmraid. Does mdadm work for you?

Comment 3 Zhang Yi 2017-10-09 02:51:42 UTC
Will try this issue with mdadm after I found HW which support ISW.

Comment 4 Jan Kurik 2017-12-06 10:43:03 UTC
Red Hat Enterprise Linux 6 is in the Production 3 Phase. During the Production 3 Phase, Critical impact Security Advisories (RHSAs) and selected Urgent Priority Bug Fix Advisories (RHBAs) may be released as they become available.

The official life cycle policy can be reviewed here:

http://redhat.com/rhel/lifecycle

This issue does not meet the inclusion criteria for the Production 3 Phase and will be marked as CLOSED/WONTFIX. If this remains a critical requirement, please contact Red Hat Customer Support to request a re-evaluation of the issue, citing a clear business justification. Note that a strong business justification will be required for re-evaluation. Red Hat Customer Support can be contacted via the Red Hat Customer Portal at the following URL:

https://access.redhat.com/