Bug 746254

Summary: Kernel: dm-log-userspace not properly registering log devices
Product: Red Hat Enterprise Linux 6 Reporter: Jonathan Earl Brassow <jbrassow>
Component: kernelAssignee: Jonathan Earl Brassow <jbrassow>
Status: CLOSED ERRATA QA Contact: Chao Yang <chyang>
Severity: medium Docs Contact:
Priority: medium    
Version: 6.2CC: agk, arozansk, cmarthal, czhang, mbroz, prajnoha, qcai, syeghiay
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: All   
Whiteboard:
Fixed In Version: kernel-2.6.32-215.el6 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-12-06 14:17:39 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 743112    

Description Jonathan Earl Brassow 2011-10-14 14:44:23 UTC
dm-log-userspace is a module that allows device-mapper mirror logs to be processed in userspace.  It acts as a communication bridge between the log API and userspace servers.

Since all log processing belongs to the userspace server, there was no way for the kernel module to call 'dm_get_device' on the log device.  This call is essential for properly creating dependency chains that are later queried by applications like LVM.  Without this correct information, LVM does not function properly.

The solution is to allow return data from the userspace log server during the instantiation of the log.  The return data contains the name of the log device (if there is one) that the kernel can then use to call 'dm_get_device'.  This solves the problem of the unlinked log.

Comment 1 RHEL Program Management 2011-10-14 14:51:01 UTC
This request was evaluated by Red Hat Product Management for inclusion
in a Red Hat Enterprise Linux maintenance release. Product Management has 
requested further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed 
products. This request is not yet committed for inclusion in an Update release.

Comment 3 Aristeu Rozanski 2011-10-31 18:03:52 UTC
Patch(es) available on kernel-2.6.32-215.el6

Comment 6 Corey Marthaler 2011-11-03 22:00:52 UTC
This now fixes the issue in bug 743112.

Comment 9 errata-xmlrpc 2011-12-06 14:17:39 UTC
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHSA-2011-1530.html