Bug 524609

Summary: kdump kernel hangs at udev
Product: Red Hat Enterprise Linux 5 Reporter: Jon Thomas <jthomas>
Component: udevAssignee: Harald Hoyer <harald>
Status: CLOSED CURRENTRELEASE QA Contact: BaseOS QE <qe-baseos-auto>
Severity: high Docs Contact:
Priority: high    
Version: 5.2CC: pknirsch, tao
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2009-10-13 14:12:07 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On:    
Bug Blocks: 499522    
Attachments:
Description Flags
log of udev hang
none
log of udev hang none

Description Jon Thomas 2009-09-21 13:19:17 UTC 
This specific system hangs at udev during a boot to kdump kernel.

* ProLiant DL585 G5 (4 CPUs x Quad = 16 CPUs booted)
 - Quad-Core AMD Opteron(tm) Processor 8354
 - system name: paumaccg101a, RHEL5.2 with 2.6.18-92.el5 (x86_64)

This only happens when the qla driver is loaded. 

The test is symply sysrq to force crash. The kdump kernel will load, but then hangs later during udev. It should write out the core and then reboot.

Everything works when udev is disabled.

We thought we might be hitting https://bugzilla.redhat.com/show_bug.cgi?id=460301, but we have eliminated that.
Comment 1 Jon Thomas 2009-09-21 13:23:58 UTC 
Additional info:

We have tested this on our hardware, but could not reproduce this..but we don't have the same storage config. The customer has had a couple different machines (same model) with the issue.
Comment 2 Phil Knirsch 2009-10-12 12:37:58 UTC 
Have you run udev in debug mode and logged it via a serial console? That would provide a lot more valuable info on what happens.

Thanks & regards, Phil
Comment 3 Jon Thomas 2009-10-12 13:52:24 UTC 
We collected udev debug from serial, but I didn't see anything that stood out and the "hang" didn't appear to happen at a consistent location. I'm been informed of the following tests.



1./ Install From Scratch of RH5.4 (with the customer's Configuration)
   ==>  Crash tests: OK

2./ Update from RH5.2 (customer Configuration)

a)  Kernel update  (2.6.18-164)       ==> Crash tests : Not OK (same problem)
  
   Updating also the following RPMs :
   - RPM "trouser" (not installed in  RH5.2 or RH5.4 From Scratch : needed
     to  update the kernel ? )
   - RPM  "keyutils (update)
   - RPM  " ecryptfs" (update)
   - RPM "KERNEL"

b) Update of Package KEXEC (RHEL 5.4)  ==>  Crash tests  : OK
Comment 4 Jon Thomas 2009-10-12 13:53:26 UTC 
Created attachment 364460 [details]
log of udev hang
Comment 5 Jon Thomas 2009-10-12 13:54:19 UTC 
Created attachment 364462 [details]
log of udev hang

Attached a couple logs of udev debug output