Bug 1993290

Summary:	thin_repair should clear the needs_check flag in the repaired metadata
Product:	Red Hat Enterprise Linux 8	Reporter:	Ming-Hung Tsai <mtsai>
Component:	device-mapper-persistent-data	Assignee:	Ming-Hung Tsai <mtsai>
Status:	CLOSED ERRATA	QA Contact:	Filip Suba <fsuba>
Severity:	low	Docs Contact:
Priority:	low
Version:	8.5	CC:	agk, fsuba, heinzm, lvm-team, mcsontos, msnitzer, thornber
Target Milestone:	beta	Keywords:	Triaged
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	device-mapper-persistent-data-0.9.0-4.el8	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-09 19:51:17 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description Ming-Hung Tsai 2021-08-12 17:27:56 UTC

Description of problem:

From the user perspective, a repaired metadata built by thin_repair should be clean and without the needs_check flag that imposes further examination. Therefore, thin_repair should remove the needs_check flag if it is present in the source metadata.

thin_restore should follow the same rule.

Users can barely find this issue since RHEL is shipped with thin_check-enabled by default, the flag therefore is automatically removed during volume activation.


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

0.9.0-3.el8


Steps to Reproduce:

1. Create a flagged metadata using thin_restore (requires dmpd 0.9.0-3.el8 or older versions):

# dd if=/dev/zero of=src.bin bs=1M count=4
# thin_restore -i input.xml -o src.bin

in which input.xml 

2. Repair the flagged source metadata

# dd if=/dev/zero of=dest.bin bs=1M count=4
# thin_repair -i src.bin -o dest.bin

3. Check presence of the needs_check flag in the dest metadata

# thin_dump dest.bin


Actual results:
<superblock uuid="" time="1" transaction="1" flags="1"

Expected results:
The superblock flag should be zeroed
<superblock uuid="" time="1" transaction="1" flags="0" ... >

Comment 1 Ming-Hung Tsai 2021-08-12 17:48:21 UTC

The patch has been upstreamed
https://github.com/jthornber/thin-provisioning-tools/commit/c32517f827f04f4f079a0913fa25b57b8b4c2960

And here's the backport for dmpd v0.9.0, as well as the test cases
https://github.com/mingnus/thin-provisioning-tools/commit/6b698fb7a4205d629dfcfdbbb158ec176ee05f40

Two new test cases are introduced for testing the reproduce steps above.

# ./configure --enable-testing ...
# make functional-test

...
thin-repair
  clear-needs-check-flag ................................... pass
  ...
thin-restore
  clear-needs-check-flag ................................... pass

Comment 3 Ming-Hung Tsai 2021-08-16 15:30:36 UTC

Updated patch
https://github.com/mingnus/thin-provisioning-tools/commit/62536defc86f12363e4178ee5a2cefc40fa416d9

Comment 6 Filip Suba 2021-08-27 11:05:16 UTC

Verified with device-mapper-persistent-data-0.9.0-4.el8.

Comment 10 errata-xmlrpc 2021-11-09 19:51:17 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 (device-mapper-persistent-data bug fix and enhancement update), and where to find the updated
files, follow the link below.

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

https://access.redhat.com/errata/RHBA-2021:4457