[GFS2] Red Hat bz 228540: owner references
commit04b933f27bc8e7f3f6423020cec58a4eab3bb7a7
authorRobert Peterson <rpeterso@redhat.com>
Fri, 23 Mar 2007 22:05:15 +0000 (23 17:05 -0500)
committerSteven Whitehouse <swhiteho@redhat.com>
Tue, 1 May 2007 08:10:55 +0000 (1 09:10 +0100)
tree992d9dd401b81ccb0b1f166fabd3ca315806361e
parent172e045a7fcc3ee647fa70dbd585a3c247b49cb2
[GFS2] Red Hat bz 228540: owner references

In Testing the previously posted and accepted patch for
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=228540
I uncovered some gfs2 badness.  It turns out that the current
gfs2 code saves off a process pointer when glocks is taken
in both the glock and glock holder structures.  Those
structures will persist in memory long after the process has
ended; pointers to poisoned memory.

This problem isn't caused by the 228540 fix; the new capability
introduced by the fix just uncovered the problem.

I wrote this patch that avoids saving process pointers
and instead saves off the process pid.  Rather than
referencing the bad pointers, it now does process lookups.
There is special code that makes the output nicer for
printing holder information for processes that have ended.

This patch also adds a stub for the new "sprint_symbol"
function that exists in Andrew Morton's -mm patch set, but
won't go into the base kernel until 2.6.22, since it adds
functionality but doesn't fix a bug.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
fs/gfs2/glock.c
fs/gfs2/glock.h
fs/gfs2/incore.h