On Thu, 2024-04-04 at 14:23 -0700, Andrew Morton wrote: > On Tue, 02 Apr 2024 00:24:28 -0600 Vishal Verma <vishal.l.verma@xxxxxxxxx> wrote: > > > In [1], Dan points out that all of the WARN_ON_ONCE() usage in the > > referenced patch should be replaced with lockdep_assert_held(_write)(). > > > > Replace those, and additionally, replace a couple of other > > WARN_ON_ONCE() introduced in the same patch for actual failure > > cases (i.e. when acquiring a semaphore fails in a remove / unregister > > path) with dev_WARN_ONCE() as is the precedent here. > > > > Recall that previously, unregistration paths was implicitly protected by > > overloading the device lock, which the patch in [1] sought to remove. > > This meant adding a semaphore acquisition in these unregistration paths. > > Since that can fail, and it doesn't make sense to return errors from > > these paths, retain the two instances of (now) dev_WARN_ONCE(). > > > > ... > > > > @@ -471,6 +471,7 @@ static void __unregister_dev_dax(void *dev) > > > > dev_dbg(dev, "%s\n", __func__); > > > > + lockdep_assert_held_write(&dax_region_rwsem); > > kill_dev_dax(dev_dax); > > device_del(dev); > > free_dev_dax_ranges(dev_dax); > > This is new and unchangelogged? > > I'm taking Dan's reply to your patch as Not-A-Nack ;) > True, but with Dan's new feedback, that results in a bit more rework, this will likely turn into 2-3 patches. Working on it now, will be out shortly!
