BUG: spinlock recursion (sys_chdir, user_path_at, do_path_lookup ...)

On Wed, 2011-01-12 at 23:52 +0100, Thomas Gleixner wrote:

On Wed, 12 Jan 2011, Uwe Kleine-K?nig wrote:

quoted

quoted

Reverting: fs: rcu-walk aware d_revalidate method
commit: 34286d6662308d82aed891852d04c7c3a2649b16

I found that one, too, in the meantime.  Currently debugging that with
tglx on irc.

The last finding is that parent and dentry in
nameidata_dentry_drop_rcu() are the same, which explains the lock
recursion nicely. 

@nick: Anything you want us to add to the debugging ?

@peterz: Why does lockdep ignore the lock recursion in that
         spin_lock_nested() call?

$ git show 34286d6662308d82aed891852d04c7c3a2649b16 | grep spin_lock_nested | wc -l
0

Uhm, whot?!