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
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat Enterprise Linux 5
Classification: Red Hat
Component: kernel
Version: 5.0
Hardware: ppc64
OS: Linux
medium
medium
Target Milestone: ---
: ---
Assignee: Doug Ledford
QA Contact: Brian Brock
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2006-10-10 16:33 UTC by Paul Clements
Modified: 2008-05-21 14:39 UTC (History)
1 user (show)

Fixed In Version: RHBA-2008-0314
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2008-05-21 14:39:53 UTC
Target Upstream Version:
Embargoed:

Attachments (Terms of Use)
patch (1.10 KB, patch)
2006-10-10 16:33 UTC, Paul Clements 		no flags Details | Diff
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Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2008:0314 0 normal SHIPPED_LIVE Updated kernel packages for Red Hat Enterprise Linux 5.2 2008-05-20 18:43:34 UTC

Description Paul Clements 2006-10-10 16:33:19 UTC 
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 16:33:19 UTC 
Created attachment 138158 [details]
patch
Comment 2 Linda Wang 2008-01-02 20:30:34 UTC 
patch posted 12/04/07.
Comment 4 Don Zickus 2008-01-08 20:45:49 UTC 
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 21:29:06 UTC 
Confirmed the fix is in the -87.el5 kernel.
Comment 8 errata-xmlrpc 2008-05-21 14:39:53 UTC 
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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