Bug 1331572

Summary:	After a live merge failure, a VM with volumes in an illegal state can be restarted
Product:	Red Hat Enterprise Virtualization Manager	Reporter:	Gordon Watson <gwatson>
Component:	vdsm	Assignee:	Ala Hino <ahino>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Natalie Gavrielov <ngavrilo>
Severity:	urgent	Docs Contact:
Priority:	urgent
Version:	3.6.4	CC:	acanan, amureini, bazulay, ebenahar, gklein, lsurette, michal.skrivanek, mkalinin, ngavrilo, ratamir, srevivo, tnisan, ycui, ykaul, ylavi
Target Milestone:	ovirt-4.0.0-alpha	Keywords:	ZStream
Target Release:	---
Hardware:	Unspecified
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	1332038 (view as bug list)		Environment:
Last Closed:	2016-05-17 12:13:11 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	Storage	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Bug Depends On:
Bug Blocks:	1332038

Description Gordon Watson 2016-04-28 20:36:08 UTC

Description of problem:

A specific live merge can leave volumes in an illegal state, e.g. as a result of BZ 1314082.

In this case the merge actually completes on the host, but the merged volumes are not removed from with the storage domain or the database.

If the VM were to be restarted in this state, it would restart successfully with the active volume of each disk now being the original leaf volume, i.e. the one merged from and the one that should have been previously removed.

This can result in out-of-date data blocks being accessed, if the parent volume had been written to after the merge had completed.

If a subsequent merge is performed, again potentially out-of-date blocks might be merged back.


Version-Release number of selected component (if applicable):

RHEV 3.6.4
RHEL 7.2 host;
   vdsm-4.17.23-0.el7ev


How reproducible:

Every time.


Steps to Reproduce:
1. Encounter BZ 1314082.
2. Restart the VM.

OR:

1. Create a VM with one disk.
2. Create a snapshot.
3. Modify the database to set the base image's imagestatus = 4 (illegal).
4. On the SPM host, change the 'LEGALITY' field in the volume metadata for the leaf volume to "ILLEGAL".
5. Start the VM.


Actual results:

VM starts up with an 'out-of-date' active volume.


Expected results:

VM not allowed to start.


Additional info:

Comment 4 Ala Hino 2016-05-01 14:24:42 UTC

This bug is was fixed, verified and closed as part of BZ 1206722.

Up to qa contact to decide how to proceed.

Comment 5 Elad 2016-05-09 11:06:50 UTC

Changing the need-info to Natalie as she is the QA contact for this bug

Comment 6 Natalie Gavrielov 2016-05-17 12:13:11 UTC

(In reply to Ala Hino from comment #4)
> This bug is was fixed, verified and closed as part of BZ 1206722.
> 
> Up to qa contact to decide how to proceed.

Following above comment, closing.