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Bug 455504

Summary: Backport of don't use large pages to map the first 2/4MB of memory form 2.6.26 to RHEL5-U3
Product: Red Hat Enterprise Linux 5 Reporter: Larry Woodman <lwoodman>
Component: kernelAssignee: Larry Woodman <lwoodman>
Status: CLOSED ERRATA QA Contact: Martin Jenner <mjenner>
Severity: medium Docs Contact:
Priority: medium    
Version: 5.3CC: dzickus, mgahagan, prarit
Target Milestone: rc   
Target Release: ---   
Hardware: i386   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2009-01-20 20:15:53 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:
Bug Depends On:    
Bug Blocks: 455409    
Attachments:
Description Flags
Patch to use 4KB pages for first 2MB of kernel space. none

Description Larry Woodman 2008-07-15 19:26:47 UTC 
Description of problem:

Intel recommends to not use large pages for the first 1MB
of the physical memory because there are fixed size MTRRs there
which cause splitups in the TLBs.

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

RHEL5-U3

How reproducible:

N/A

Steps to Reproduce:
1.
2.
3.
  
Actual results:

Using 2MB pages for first 2MB of kernel memory

Expected results:

Use 4KB pages for first 2MB of kernel memory.

Additional info:
Comment 1 Larry Woodman 2008-07-15 19:26:47 UTC 
Created attachment 311875 [details]
Patch to use 4KB pages for first 2MB of kernel space.
Comment 3 RHEL Program Management 2008-07-31 19:02:21 UTC 
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.
Comment 4 Don Zickus 2008-09-09 21:16:38 UTC 
in kernel-2.6.18-109.el5
You can download this test kernel from http://people.redhat.com/dzickus/el5
Comment 8 errata-xmlrpc 2009-01-20 20:15:53 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 therefore 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/RHSA-2009-0225.html