GFS2: filesystem hang caused by incorrect lock order
This patch fixes a deadlock in GFS2 where two processes are trying
to reclaim an unlinked dinode:
One holds the inode glock and calls gfs2_lookup_by_inum trying to look
up the inode, which it can't, due to I_FREEING. The other has set
I_FREEING from vfs and is at the beginning of gfs2_delete_inode
waiting for the glock, which is held by the first. The solution is to
add a new non_block parameter to the gfs2_iget function that causes it
to return -ENOENT if the inode is being freed.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/dir.c b/fs/gfs2/dir.c
index 5c356d0..f789c57 100644
--- a/fs/gfs2/dir.c
+++ b/fs/gfs2/dir.c
@@ -1506,7 +1506,7 @@
inode = gfs2_inode_lookup(dir->i_sb,
be16_to_cpu(dent->de_type),
be64_to_cpu(dent->de_inum.no_addr),
- be64_to_cpu(dent->de_inum.no_formal_ino));
+ be64_to_cpu(dent->de_inum.no_formal_ino), 0);
brelse(bh);
return inode;
}