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From: Pete French <petefrench@ticketswitch.com>
Date: Sun, 11 Jan 2009 17:16:05 +0000
Subject: Lock order reversals using bce in 7.1
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Here is a better set of images. This machine was compiled
with the following config file:

include         GENERIC
ident           DEBUG

options         KDB
options         DDB
options         SW_WATCHDOG
options         DEBUG_VFS_LOCKS
options         MUTEX_DEBUG
options         WITNESS
options         WITNESS_KDB
options         LOCK_PROFILING
options         INVARIANTS
options         INVARIANT_SUPPORT
options         DIAGNOSTIC

On booting it almost immediately does this:

        http://www.twisted.org.uk/~pete/71_lor.png

The output of trace, show pcpu, show locks, show allpcpu and show alllocks
are shown in the following images:

        http://www.twisted.org.uk/~pete/71_locks_trace.png
        http://www.twisted.org.uk/~pete/71_pcpu_alllocks.png
        http://www.twisted.org.uk/~pete/71_allpcpu1.png
        http://www.twisted.org.uk/~pete/71_allpcpu2.png

I am going to revent the machine back to a normal kernel now - is there
anything I might be able to do to stop this, or do I need to roll everything
back to 7.0 ?

cheers,

-pete.