Subject: Re: [PATCH 2/2] sysctl: lockdep support for sysctl reference counting.

From: Andrew Morton <[email-masked]>
Date: Fri, 10 Apr 2009 02:18:54 -0700

On Sat, 21 Mar 2009 00:42:19 -0700 [email-masked] (Eric W. Biederman) wrote:

> It is possible for get lock ordering deadlocks between locks
> and waiting for the sysctl used count to drop to zero.  We have
> recently observed one of these in the networking code.
> 
> So teach the sysctl code how to speak lockdep so the kernel
> can warn about these kinds of rare issues proactively.

`make headers_check':

/usr/src/25/usr/include/linux/sysctl.h:31: included file 'linux/lockdep.h' is not exported
make[2]: *** [/usr/src/25/usr/include/linux/.check] Error 1

It looks like we'll need version 2 on these patches..