Date: Thu, 7 Sep 2017 08:59:33 +0900
From: Byungchul Park <byungchul.park@lge.com>
To: Boqun Feng <boqun.feng@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>,
        Byungchul Park <max.byungchul.park@gmail.com>,
        Ingo Molnar <mingo@kernel.org>, Tejun Heo <tj@kernel.org>,
        david@fromorbit.com, Johannes Berg <johannes@sipsolutions.net>,
        oleg@redhat.com,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        kernel-team@lge.com
Subject: Re: [PATCH 4/4] lockdep: Fix workqueue crossrelease annotation
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On Wed, Sep 06, 2017 at 10:32:54AM +0900, Byungchul Park wrote:
> Moreover, it's also possible to generate more false ones between the
> pseudo acquisitions, if real acquisitions are used for that speculative
> purpose e.i. recursive-read here, which are anyway real ones.

Of course, this problem can be ignored if we *only* use recursive-read
acquisitions for the speculative purpose, though current workqueue
code uses both recursive-read and normal(write) for that.

IOW, as long as we leave the write acquisions for that purpose, this
would still be a problem.