Bug 753704

Summary: Memory information is incorrect under RHEL6.1 32bit OS
Product: Red Hat Enterprise Linux 6 Reporter: zou.chris
Component: kernelAssignee: Neil Horman <nhorman>
Status: CLOSED NOTABUG QA Contact: Desktop QE <desktop-qa-list>
Severity: urgent Docs Contact:
Priority: unspecified    
Version: 6.1CC: nhorman, syeghiay, tpelka
Target Milestone: rc   
Target Release: 6.1   
Hardware: i386   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Intel Romely Platform
Last Closed: 2011-12-19 18:37:07 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 767187    

Description zou.chris 2011-11-14 08:36:39 UTC 
Description of problem:
Memory information is incorrect under RHEL6.1 32bit OS

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


How reproducible:


Steps to Reproduce:
1. Configure the system.
2. Install RHEL6.1 32bit OS.
3. Type "cat /proc/meminfo", MemTotal is only showed 14GB when 48GB DIMMs populated on board==>Fail
  
Actual results:


Expected results:


Additional info:
1.We try another thurley platform, the memory size is also fail.
2.It seems OS issue.
Comment 1 zou.chris 2011-11-14 08:46:45 UTC 
1.RHEL5.7 32bit -->Memory size is OK, 48G when the same Server-->PASS
Comment 3 Neil Horman 2011-12-16 21:14:26 UTC 
Need to find a system with enough ram to try reproduce this
Comment 4 Neil Horman 2011-12-19 18:37:07 UTC 
Ah, I see, this is actually consistent and working as designed.  We used to allow an almost unlimited amount of ram on 32 bit systems, which led to resource exhaustion problems (tracking all that ram), and so we limited how much ram 32 bit systems could sanely support.  Its restricted based on the level of extra PAE bits that are available but caps out at 16Gb, which is what you're seeing.  the problem was fixed upstream and backported to rhel5 as commit 014a0bd0e0f429f01494b3a0a117961120023ad1, against bz 465373.

This is working as designed.