Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 766702

Summary: file could not determine XZ archive
Product: Red Hat Enterprise Linux 6 Reporter: Miroslav Suchý <msuchy>
Component: fileAssignee: Jan Kaluža <jkaluza>
Status: CLOSED DUPLICATE QA Contact: BaseOS QE Security Team <qe-baseos-security>
Severity: low Docs Contact:
Priority: low    
Version: 6.2CC: ovasik
Target Milestone: rc   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2011-12-13 07:47:20 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:

Description Miroslav Suchý 2011-12-12 15:19:59 UTC 
Take initramdisk of rhel 6.2, which is cpio archive packed by XZ.
And run it through file:

$ file /tmp/initrd.img
/tmp/initrd.img: data

It happens on RHEL6 and even on Fedora 16.

And despite the fact that 
/usr/share/misc/magic
contains:
# http://tukaani.org/xz/xz-file-format.txt
0       ustring         \xFD7zXZ\x00            XZ compressed data
!:mime  application/x-xz

Additional info:
$ hexdump /tmp/initrd.img|head -n5
0000000 005d 0000 ff04 ffff ffff ffff 00ff 0d18
0000010 04dd 8363 7421 c707 f6d2 d69f 1091 7626
0000020 0ade 0f1f 48db 24ef 121f a4ba 5962 b486
0000030 2e9d 164c 96ae 9776 d317 8071 1d28 5c89
0000040 43d7 26d6 370f 1349 3018 8c78 a86b 874d
Comment 1 Jan Kaluža 2011-12-13 07:47:20 UTC 
This is LZMA compression. There's already bug for RHEL6 mentioning initrd.img. Closing as DUPLICATE.

*** This bug has been marked as a duplicate of bug 747999 ***