Re: [PATCH 2/2] workqueue: create lockdep dependency in flush_work()

On Tue, Aug 21, 2018 at 02:03:17PM +0200, Johannes Berg wrote:

From: Johannes Berg <redacted>

In flush_work(), we need to create a lockdep dependency so that
the following scenario is appropriately tagged as a problem:

  work_function()
  {
    mutex_lock(&mutex);
    ...
  }

  other_function()
  {
    mutex_lock(&mutex);
    flush_work(&work); // or cancel_work_sync(&work);
  }

This is a problem since the work might be running and be blocked
on trying to acquire the mutex.

Signed-off-by: Johannes Berg <redacted>

This makes sense to me.  Did you notice any extra lockdep warnings
with this?

Thanks.

-- 
tejun