On Mon, Oct 24, 2011 at 11:24:51AM +0200, Thomas Gleixner wrote:

On Mon, 24 Oct 2011, Yong Zhang wrote:

quoted

On Wed, Oct 19, 2011 at 11:12:20AM +0200, Thomas Gleixner wrote:

quoted

On Sun, 16 Oct 2011, Yong Zhang wrote:

quoted

Fix below false positive (seems this is not a real deadlock scenario)
lockdep warning:

This looks like you caused it with patch 1.

Hmmm, yup.
CPU_DOWN_PREPARE will be under cpu_hotplug.lock.

quoted

Both need a bit more
thought, but thanks for catching that.

No sure whether it's big issue or not.
Mind showing more about your concern?

This is probably not the only place which will run into that issue and
I have not much interest to patch all those sites.

If so, I think that kind of violation has been caught in mainline,
because mainline has had CPU_DOWN_PREPARE called under
cpu_hotplug.lock, right?

Or am I missing something?

Thanks,
Yong