Bug 463734

Summary:	Page ffffe000-fffff000 has invalid permissions
Product:	Red Hat Enterprise Linux 4	Reporter:	john.haxby <john.haxby>
Component:	kernel	Assignee:	Larry Woodman <lwoodman>
Status:	CLOSED WONTFIX	QA Contact:	Martin Jenner <mjenner>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	4.7	CC:	lwoodman
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:	2012-06-20 16:09:13 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 john.haxby@oracle.com 2008-09-24 12:40:02 UTC

Description of problem:

In bug 210779, comment #5 says that this page is mapped read-only for the kernel and not the user process and, later, points out that this entry does not appear in /proc/<pid>/maps for later releases.   It would seem that the fix which crept into i386 when it shouldn't have.

Version-Release number of selected component (if applicable): 2.6.9-67.EL (for example)


How reproducible: always

Steps to Reproduce:
1. grep ^ffff /proc/self/maps
  
Actual results:

Observe that there is a map starting at ffffe000 and that it is, supposedly accessible.

Note that mprotect, for example, for an address in this range will return ENOMEN indicating that the page isn't accessible.  Note also that this region is conspicuous by its absence on an RHEL5 machine.


Expected results:

The region should be marked inaccessible or not there at all.


Additional info:

Comment 1 Jiri Pallich 2012-06-20 16:09:13 UTC

Thank you for submitting this issue for consideration in Red Hat Enterprise Linux. The release for which you requested us to review is now End of Life. 
Please See https://access.redhat.com/support/policy/updates/errata/

If you would like Red Hat to re-consider your feature request for an active release, please re-open the request via appropriate support channels and provide additional supporting details about the importance of this issue.