From mboxrd@z Thu Jan  1 00:00:00 1970
From: Steven Whitehouse <swhiteho@redhat.com>
Date: Tue, 12 Aug 2008 09:53:20 +0100
Subject: [Cluster-devel] [GFS2 Patch] bz458289: rm on multiple nodes
	causes panic
In-Reply-To: <1218512508.9521.117.camel@technetium.msp.redhat.com>
References: <1218512508.9521.117.camel@technetium.msp.redhat.com>
Message-ID: <1218531200.3426.1.camel@localhost.localdomain>
List-Id: <cluster-devel.redhat.com>
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Hi,

This looks like the correct lock order to me. I guess it must be the
"other" process thats violating the correct order?

Steve.

On Mon, 2008-08-11 at 22:41 -0500, Bob Peterson wrote:
> This patch fixes a problem whereby simultaneous delete operations
> (e.g. rm -fR *) from multiple nodes on the same GFS2 file system
> can cause kernel panics, hangs, and/or memory corruption.
> 
> Regards,
> 
> Bob Peterson
> 
> Signed-off-by: Bob Peterson <rpeterso@redhat.com>
> --
>  fs/gfs2/ops_inode.c |   24 ++++++------------------
>  1 files changed, 6 insertions(+), 18 deletions(-)
> 
> diff --git a/fs/gfs2/ops_inode.c b/fs/gfs2/ops_inode.c
> index e2c62f7..a072c9a 100644
> --- a/fs/gfs2/ops_inode.c
> +++ b/fs/gfs2/ops_inode.c
> @@ -288,25 +288,17 @@ static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
>  	gfs2_holder_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, ghs + 2);
>  
> 
> -	error = gfs2_glock_nq(ghs); /* parent */
> -	if (error)
> -		goto out_parent;
> -
> -	error = gfs2_glock_nq(ghs + 1); /* child */
> -	if (error)
> -		goto out_child;
> -
> -	error = gfs2_glock_nq(ghs + 2); /* rgrp */
> +	error = gfs2_glock_nq_m(3, ghs);
>  	if (error)
> -		goto out_rgrp;
> +		goto out;
>  
>  	error = gfs2_unlink_ok(dip, &dentry->d_name, ip);
>  	if (error)
> -		goto out_rgrp;
> +		goto out;
>  
>  	error = gfs2_trans_begin(sdp, 2*RES_DINODE + RES_LEAF + RES_RG_BIT, 0);
>  	if (error)
> -		goto out_rgrp;
> +		goto out;
>  
>  	error = gfs2_dir_del(dip, &dentry->d_name);
>          if (error)
> @@ -316,14 +308,10 @@ static int gfs2_unlink(struct inode *dir, struct dentry *dentry)
>  
>  out_end_trans:
>  	gfs2_trans_end(sdp);
> -	gfs2_glock_dq(ghs + 2);
> -out_rgrp:
> +out:
> +	gfs2_glock_dq_m(3, ghs);
>  	gfs2_holder_uninit(ghs + 2);
> -	gfs2_glock_dq(ghs + 1);
> -out_child:
>  	gfs2_holder_uninit(ghs + 1);
> -	gfs2_glock_dq(ghs);
> -out_parent:
>  	gfs2_holder_uninit(ghs);
>  	gfs2_glock_dq_uninit(&ri_gh);
>  	return error;
> 
>