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Date: Wed, 3 Jan 2018 02:05:56 -0500
From: Theodore Ts'o <tytso@mit.edu>
To: Byungchul Park <byungchul.park@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>,
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Subject: Re: About the try to remove cross-release feature entirely by Ingo
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On Wed, Jan 03, 2018 at 11:10:37AM +0900, Byungchul Park wrote:
> > The point I was trying to drive home is that "all we have to do is
> > just classify everything well or just invalidate the right lock
> 
> Just to be sure, we don't have to invalidate lock objects at all but
> a problematic waiter only.

So essentially you are proposing that we have to play "whack-a-mole"
as we find false positives, and where we may have to put in ad-hoc
plumbing to only invalidate "a problematic waiter" when it's
problematic --- or to entirely suppress the problematic waiter
altogether.  And in that case, a file system developer might be forced
to invalidate a lock/"waiter"/"completion" in another subsystem.

I will also remind you that doing this will trigger a checkpatch.pl
*error*:

ERROR("LOCKDEP", "lockdep_no_validate class is reserved for device->mutex.\n" . $herecurr);

	 		      	       		- Ted