=Comment: #0=================================================
Emily J. Ratliff <ratliff.com> - 
1. Feature Overview:
Feature Id:	[201996]
a. Name of Feature:	CPU_DYING notifiers
b. Feature Description
When kvm-intel.ko is loaded, regardless of whether any virtual machines 
 are running, offlining/onlining of physical CPUs on the host results in 
 failure.  This can lead to confusion from a user because it is not 
 obvious that CPU hotplug failed due to the kvm module being loaded.  
 Hotplug fails because 2.6.18 lacked sufficient infrastructure to notify 
 KVM so that it could disable/enable virtualization support on the 
 removed/added physical CPUs.  This infrastructure has subsequently been 
 added to Linux by:
 
 commit db912f963909b3cbc3a059b7528f6a1a1eb6ffae
 Author: Avi Kivity <avi>
 Date:   Thu May 24 12:23:10 2007 +0300
 
     HOTPLUG: Add CPU_DYING notifier
    
     KVM wants a notification when a cpu is about to die, so it can disable
     hardware extensions, but at a time when user processes cannot be 
 scheduled
     on the cpu, so it doesn't try to use virtualization extensions after 
 they
     have been disabled.
    
     This adds a CPU_DYING notification.  The notification is called in 
 atomic
     context on the doomed cpu.
    
     Signed-off-by: Avi Kivity <avi>
 
 See http://lkml.org/lkml/2007/5/24/108 for the full series.
 
 
 See Bug 54637 <https://bugzilla.linux.ibm.com/show_bug.cgi?id=54637>  -  
 RIT320894- CPU onlining fails with I/O error when kvm_intel is loaded

2. Feature Details:
Sponsor:	LTC
Architectures:
x86_64

Arch Specificity: Purely Common Code
Affects Core Kernel: Yes
Delivery Mechanism: Backport
Category:	xSeries
Request Type:	Kernel - Enhancement from Upstream
d. Upstream Acceptance:	Accepted
Sponsor Priority	1
f. Severity: High
IBM Confidential:	no
Code Contribution:	3rd party code
g. Component Version Target:	

3. Business Case
Make Virtualization more robust..

4. Primary contact at Red Hat: 
John Jarvis
jjarvis

5. Primary contacts at Partner:
Project Management Contact:
Stephanie Glass, sglass.com

Technical contact(s):
Frank Novak, fnovak.com
Anthony Liguori,  aliguori.com

IBM Manager:
Warren Grunbok II, grunbok.com