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Date: Wed, 4 Apr 2018 23:14:20 -0400
From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: Waiman Long <longman@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Davidlohr Bueso <dave@stgolabs.net>,
        Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH] locking/rwsem: Add up_write_non_owner() for
 percpu_up_write()
Message-ID: <20180405031420.GB22358@thunk.org>
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On Wed, Apr 04, 2018 at 10:37:26AM -0400, Waiman Long wrote:
> The commit 8c5db92a705d ("locking/rwsem: Add DEBUG_RWSEMS to look for
> lock/unlock mismatches") causes a warning in ext4 fstests due to the
> fact that the freeze and thaw ioctls, by design, are run in different
> processes.

While true, it's not just ext4 fstests --- it's any file system which
supports freeze/thaw, since it's happening in the vfs layer.  I have
just as easily replicated the problem using "kvm-xfstests -c xfs
generic/068".  Or "kvm-xfstests -c btrfs generic/068".

Cheers,

						- Ted