Bug 837963 - ext4 gets corrupted when hosting loopback filesystems due to discard
ext4 gets corrupted when hosting loopback filesystems due to discard
Status: CLOSED DUPLICATE of bug 799627
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: kernel (Show other bugs)
Unspecified Unspecified
unspecified Severity unspecified
: rc
: ---
Assigned To: Eric Sandeen
Red Hat Kernel QE team
Depends On:
  Show dependency treegraph
Reported: 2012-07-05 18:59 EDT by Eric Sandeen
Modified: 2012-07-05 19:06 EDT (History)
0 users

See Also:
Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of:
Last Closed: 2012-07-05 19:06:08 EDT
Type: Bug
Regression: ---
Mount Type: ---
Documentation: ---
Verified Versions:
Category: ---
oVirt Team: ---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---

Attachments (Terms of Use)

  None (edit)
Description Eric Sandeen 2012-07-05 18:59:19 EDT
When using ext4 as the backing device for a loopback xfs filesystem, it gets corrupted during an xfstests run.

A short reproducer is to configure the test device as xfs, and make the scratch device a 10G loopback filesystem, hosted on ext4.  Then run ./check 167 168

This is due the discards issued by mkfs.xfs during the test, which punches holes in the ext4 file, and ends up corrupting it.  It's fixed upstream by:

commit 5f95d21fb6f2aaa52830e5b7fb405f6c71d3ab85
Author: Lukas Czerner <lczerner@redhat.com>
Date:   Mon Mar 19 23:03:19 2012 -0400

    ext4: rewrite punch hole to use ext4_ext_remove_space()

Note You need to log in before you can comment on or make changes to this bug.