Bug 200444

Summary:	echo c > /proc/sysrq-trigger does not cause a crash
Product:	[Fedora] Fedora	Reporter:	Barry Donahue <bdonahue>
Component:	kernel	Assignee:	Kernel Maintainer List <kernel-maint>
Status:	CLOSED DUPLICATE	QA Contact:	Brian Brock <bbrock>
Severity:	medium	Docs Contact:
Priority:	high
Version:	6	CC:	jlayton, wtogami
Target Milestone:	---
Target Release:	---
Hardware:	i386
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2006-08-18 14:34:29 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 Barry Donahue 2006-07-27 18:17:50 UTC

Description of problem:


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

kernel 2.6.17-1.2358.fc6

How reproducible: always


Steps to Reproduce:
1.echo "1" > /proc/sys/kernel/sysrq
2.echo c > /proc/sysrq-trigger
3.You will get the message- SysRq : Trigger a crash dump -but the system doesn't
crash.
  
Actual results: no crash


Expected results:crash


Additional info: echo b and echo t do work.

Comment 1 Jeff Layton 2006-08-18 02:18:25 UTC

I've done a little poking around with systemtap and have determined that
crash_kexec() is getting called, but machine_crash_shutdown() is never called.
So either this is evaluating true:

xchg(&kexec_lock, 1);

...or this is evaluating false:

xchg(&kexec_crash_image, NULL);

Working on a debug patch to determine which it is...

Comment 2 Jeff Layton 2006-08-18 13:14:41 UTC

The problem seems to be that kexec_crash_image is NULL. Looking at how and when
that gets initialized.

Comment 3 Jarod Wilson 2006-08-18 14:34:29 UTC

Check out the latest patch attached to bug 201618. :)

*** This bug has been marked as a duplicate of 201618 ***

Comment 4 Jarod Wilson 2006-08-18 14:36:56 UTC

Actually, this might be closer to a dupe of bug 198578...

kexec_crash_image gets set by starting the kdump service, which loads your kdump
kernel via kexec.