Bug 210178 – md: write behind feature does not work on big endian machines

Bug 210178 - md: write behind feature does not work on big endian machines

Summary:	md: write behind feature does not work on big endian machines

Status:	CLOSED ERRATA

Aliases:	None

Product:	Red Hat Enterprise Linux 5
Classification:	Red Hat
Component:	kernel (Show other bugs)
Sub Component:
Version:	5.0
Hardware:	ppc64 Linux

Priority	medium Severity medium
Target Milestone:	---
Target Release:	---
Assigned To:	Doug Ledford
QA Contact:	Brian Brock
Docs Contact:

URL:
Whiteboard:
Keywords:

Depends On:
Blocks:
	Show dependency tree / graph

Reported:	2006-10-10 12:33 EDT by Paul Clements
Modified:	2008-05-21 10:39 EDT (History)
CC List:	1 user (show)

See Also:
Fixed In Version:	RHBA-2008-0314
Doc Type:	Bug Fix
Doc Text:
Story Points:	---
Clone Of:
Environment:
Last Closed:	2008-05-21 10:39:53 EDT
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

Attachments	(Terms of Use)
patch (1.10 KB, patch) 2006-10-10 12:33 EDT, Paul Clements	no flags	Details \| Diff
Add an attachment (proposed patch, testcase, etc.)

Groups: None (edit)

Description Paul Clements 2006-10-10 12:33:19 EDT

Description of problem:

There is a bug in the md driver. find_first_set_bit doesn't find the
least-significant bit on bigendian machines, so it is really wrong to use it.

ffs is closer, but takes an 'int' and we have a 'unsigned long'.  So use
ffz(~X) to convert a chunksize into a chunkshift.

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

kernel 2.6.17-1.2519.4.21.el5

Patch attached (patch is now in mainline).

Comment 1 Paul Clements 2006-10-10 12:33:19 EDT

Created attachment 138158 [details]
patch

Comment 2 Linda Wang 2008-01-02 15:30:34 EST

patch posted 12/04/07.

Comment 4 Don Zickus 2008-01-08 15:45:49 EST

in 2.6.18-64.el5
You can download this test kernel from http://people.redhat.com/dzickus/el5

Comment 6 Mike Gahagan 2008-04-02 17:29:06 EDT

Confirmed the fix is in the -87.el5 kernel.

Comment 8 errata-xmlrpc 2008-05-21 10:39:53 EDT

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on the solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2008-0314.html

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