ocfs2 readlink hangs on

[rot]

On ubuntu 13.04 try to read symlink on ocfs2 hangs on. This is known bug in newer kernel (newer than 3.5) reported on:

https://bugzilla.kernel.org/show_bug.cgi?id=49561

Link to patch:

https://lkml.org/lkml/2013/3/2/40

[Rafael David Tinoco (rafaeldtinoco)]

inaddy@workstation:~/work/sources/kernel/linux$ git log -1 -p 30b9c9e6ba289ba3bb67cc292efcc4122ea37ae5
commit 30b9c9e6ba289ba3bb67cc292efcc4122ea37ae5
Author: Sunil Mushran <email address hidden>
Date: Fri Aug 3 13:36:17 2012

    ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path

    Commit ea022dfb3c2a4680483b00eb2fecc9fc4f6091d1 was missing a var init.

    Reported-and-Tested-by: Vincent Etienne <email address hidden>
    Signed-off-by: Sunil Mushran <email address hidden>
    Signed-off-by: Joel Becker <email address hidden>
    Signed-off-by: Al Viro <email address hidden>

diff --git a/fs/ocfs2/symlink.c b/fs/ocfs2/symlink.c
index f1fbb4b552ad..66edce7ecfd7 100644
--- a/fs/ocfs2/symlink.c
+++ b/fs/ocfs2/symlink.c
@@ -57,7 +57,7 @@
 static int ocfs2_fast_symlink_readpage(struct file *unused, struct page *page)
 {
        struct inode *inode = page->mapping->host;
- struct buffer_head *bh;
+ struct buffer_head *bh = NULL;
        int status = ocfs2_read_inode_block(inode, &bh);
        struct ocfs2_dinode *fe;
        const char *link;

AND

inaddy@workstation:~/work/sources/kernel/linux$ git log -1 -p ea022dfb3c2a4680483b00eb2fecc9fc4f6091d1
commit ea022dfb3c2a4680483b00eb2fecc9fc4f6091d1
Author: Al Viro <email address hidden>
Date: Thu May 3 11:14:29 2012

    ocfs: simplify symlink handling

    seeing that "fast" symlinks still get allocation + copy, we might as
    well simply switch them to pagecache-based variant of ->follow_link();
    just need an appropriate ->readpage() for them...

    Signed-off-by: Al Viro <email address hidden>