Created attachment 437652 [details]
vt-devfs - patch based on upstream code

thanks to ofourdan for tracing this.

Created attachment 437653 [details]
vt-ioctl-race-fix - patch based on upstream code

thanks to ofourdan for tracing this.

How did you made the tests to track the bug? Is there any script available for it?

How did you make the tests to track the bug? Is there any script available for it?

Oi Mauro,

We tested this way:
1) Install [the brewed kernel] on a test system (a kvm machine is fine, I have been able to reproduce on a virtual machine in kvm here)
2) test with the script:

   # cat testx.sh 

   #!/bin/bash
   DATE=`date +%j%H%M`
   mkdir -p /root/xorglogs_restartx
   cp /var/log/Xorg.0.log /root/xorglogs_restartx/Xorg.0.log.$DATE
   cp /var/log/Xorg.0.log.old /root/xorglogs_restartx/Xorg.0.log.old.$DATE
   /sbin/init 3
   /sbin/init 5
   exit 0

Run from within a loop, something like:

   # while $(/bin/true); do sh testx.sh; sleep 30; done

3) And check for the error:

xf86OpenConsole: Cannot open virtual console ? (Input/output error) 

   # grep console /root/xorglogs_restartx/*

Created attachment 465076 [details]
Script to start Xorg on every 12s

This is a script based on Rodrigo's script. I opted to just re-start Xorg, instead of doing init 3/init 5 to speedup the X restarts.

Created attachment 465078 [details]
Script to check the logs, in order to check if something is wrong

This script does the other part of the test: prints the number of found errors versus the amount of time Xorg were called.

I left it ran the entire day on my test machines. The result, with the fixed kernel, is:

Errors: 0/1110

(script stopped on an arbitrary number).

So, it seems that the errors don't occur with the patched kernel.

This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.

Quality Engineering Management has reviewed and declined this request.  You may
appeal this decision by reopening this request.

Reopening and flagging for 5.8

Patches have been posted for some time, moving BZ to POST. We'll be getting this into 5.7 in just a moment.

Patch(es) available in kernel-2.6.18-261.el5
You can download this test kernel (or newer) from http://people.redhat.com/jwilson/el5
Detailed testing feedback is always welcomed.

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2011-1065.html