Bug 121805

Summary:	athlon-smp kernel does not support >4GB of RAM
Product:	Red Hat Enterprise Linux 3	Reporter:	Duncan Laurie <duncan>
Component:	kernel	Assignee:	Arjan van de Ven <arjanv>
Status:	CLOSED DUPLICATE	QA Contact:	Brian Brock <bbrock>
Severity:	low	Docs Contact:
Priority:	medium
Version:	3.0	CC:	petrides, riel
Target Milestone:	---
Target Release:	---
Hardware:	athlon
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2006-02-21 19:02:48 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 Duncan Laurie 2004-04-27 23:19:37 UTC

In order to support between 4GB and 16GB of RAM in 32-bit mode
on an opteron system the kernel needs to be compiled with
the CONFIG_HIGHMEM64G option enabled.

From what I can gather, the -smp kernels should be compiled with
PAE + highpte support by enabling the CONFIG_HIGHMEM64G option,
which will also enable CONFIG_X86_PAE.  Then the -hugemem kernel
should support PAE + highpte + 4/4 split by enabling the
CONFIG_HIGHMEM64G and the CONFIG_X86_4G options.
(see the posting by Rik van Riel about this: http://www.redhat.
com/archives/taroon-beta-list/2003-August/msg00270.html)

Currently the i686-smp kernel has the HIGHMEM64G option enabled
while the athlon-smp kernel only has HIGHMEM4G enabled.  This means
it is possible to use the i686-smp kernel to run opteron system with
between 4GB and 16GB in 32-bit mode and use the hugemem kernel
on systems with >16GB.

However it seems that the athlon-smp kernel should also be compiled
with the CONFIG_HIGHMEM64G option so it looks and acts the same as
the i686-smp variant.

Steps to Reproduce:
1. Install >4GB RAM in an opteron system
2. Install and boot kernel-smp-2.4.21-9.0.3.EL.athlon.rpm

Actual Results:  recognized RAM is limited to 4GB
Expected Results:  all available RAM is recognized (up to 16GB)

Comment 1 Duncan Laurie 2004-04-27 23:35:31 UTC

I must have hit reload in the submit window for this to come
through twice.  Closing the dup...

*** This bug has been marked as a duplicate of 12801 ***

Comment 2 Red Hat Bugzilla 2006-02-21 19:02:48 UTC

Changed to 'CLOSED' state since 'RESOLVED' has been deprecated.