Bug 773376

Summary:	Only one CPU core in Core 2 Duo working in F16
Product:	[Fedora] Fedora	Reporter:	Chris Marcantonio <cmarcant>
Component:	kernel	Assignee:	Kernel Maintainer List <kernel-maint>
Status:	CLOSED ERRATA	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	high	Docs Contact:
Priority:	unspecified
Version:	16	CC:	gansalmon, itamar, jonathan, kernel-maint, madhu.chinakonda
Target Milestone:	---
Target Release:	---
Hardware:	i686
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-04-04 00:33:48 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description Chris Marcantonio 2012-01-11 17:15:35 UTC

Description of problem:
Fresh install of F16 on Macbook Pro (dual boot) only uses on CPU core in a dual core system.



Version-Release number of selected component (if applicable):
32 bit Fedora 16
kernel version 3.1.7-1.fc16.i686.PAE
Intel(R) Core(TM)2 Duo CPU     P8700  @ 2.53GHz




How reproducible:
Every time.



Steps to Reproduce:
1. add unpartitioned space at end of OS X disk
2. install rEFIt in OS X to manage dual-boot
3. install F16 to unpartitioned space
4. allow rEFIt to fix partition tables after install
5. boot system into Fedora



Actual results:
/proc/cpuinfo only shows a single core available

During boot and in dmesg, I can see:
[    0.019998] CPU 1 irqstacks, hard=f1cde000 soft=f1ce8000
[    0.019998] Booting Node   0, Processors  #1 Ok.
[    0.019998] smpboot cpu 1: start_ip = 9b000
[    5.094766] CPU1: Not responding.
[    5.094877] Brought up 1 CPUs
[    5.094879] Total of 1 processors activated (5041.85 BogoMIPS).

which seems to indicate there is a problem with CPU 1.



Expected results:
Both cores to be functional.



Additional info:
This worked just fine in F15, and both cores were fully operational.

Comment 1 Dave Jones 2012-03-22 16:40:10 UTC

[mass update]
kernel-3.3.0-4.fc16 has been pushed to the Fedora 16 stable repository.
Please retest with this update.

Comment 2 Dave Jones 2012-03-22 16:45:14 UTC

[mass update]
kernel-3.3.0-4.fc16 has been pushed to the Fedora 16 stable repository.
Please retest with this update.

Comment 3 Dave Jones 2012-03-22 16:54:04 UTC

[mass update]
kernel-3.3.0-4.fc16 has been pushed to the Fedora 16 stable repository.
Please retest with this update.

Comment 4 Chris Marcantonio 2012-04-03 21:54:44 UTC

Circling back around to this...sorry for the delay.

Newer kernels appear to be working better, and I can see both cores again.

Comment 5 Josh Boyer 2012-04-04 00:33:48 UTC

Thanks for letting us know.