Hi,

On Thu, 2009-11-05 at 14:36 -0500, Allen Belletti wrote:
> Saw an interesting and different GFS2 death this morning that I wanted
> to pass along in case anyone has insights. We have not seen any of the
> "hanging in dlm_posix_lock" since fsck'ing early Sunday morning. In any
> case I'm pretty confident that's being triggered by the creation &
> deletion of ".lock" files within Dovecot. This was something completely
> different and it left some potentially useful debug info in the logs.
>
I've made an educated guess as to what this might be. The attached patch
should fix it, if my hunch is correct. If you have the back trace I
mentioned in my previous email, we can confirm that this really is the
cause,

Steve.


>From 89fc5489d25fc0a34a367b119448a037ed162c00 Mon Sep 17 00:00:00 2001
From: Steven Whitehouse <swhiteho@redhat.com>
Date: Fri, 6 Nov 2009 11:10:51 +0000
Subject: [PATCH 27/27] GFS2: Locking order fix in gfs2_check_blk_state

In some cases we already have the rindex lock when
we enter this function.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
---
fs/gfs2/rgrp.c | 14 ++++++++++----
1 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/fs/gfs2/rgrp.c b/fs/gfs2/rgrp.c
index 8f1cfb0..0608f49 100644
--- a/fs/gfs2/rgrp.c
+++ b/fs/gfs2/rgrp.c
@@ -1710,11 +1710,16 @@ int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)
{
struct gfs2_rgrpd *rgd;
struct gfs2_holder ri_gh, rgd_gh;
+ struct gfs2_inode *ip = GFS2_I(sdp->sd_rindex);
+ int ri_locked = 0;
int error;

- error = gfs2_rindex_hold(sdp, &ri_gh);
- if (error)
- goto fail;
+ if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
+ error = gfs2_rindex_hold(sdp, &ri_gh);
+ if (error)
+ goto fail;
+ ri_locked = 1;
+ }

error = -EINVAL;
rgd = gfs2_blk2rgrpd(sdp, no_addr);
@@ -1730,7 +1735,8 @@ int gfs2_check_blk_type(struct gfs2_sbd *sdp, u64 no_addr, unsigned int type)

gfs2_glock_dq_uninit(&rgd_gh);
fail_rindex:
- gfs2_glock_dq_uninit(&ri_gh);
+ if (ri_locked)
+ gfs2_glock_dq_uninit(&ri_gh);
fail:
return error;
}
--
1.6.2.5