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Date:   Fri, 30 Oct 2020 10:55:54 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Boqun Feng <boqun.feng@gmail.com>
Cc:     Chris Wilson <chris@chris-wilson.co.uk>,
        linux-kernel@vger.kernel.org, linux-tip-commits@vger.kernel.org,
        tip-bot2 for Peter Zijlstra <tip-bot2@linutronix.de>,
        Qian Cai <cai@redhat.com>, x86 <x86@kernel.org>
Subject: Re: [tip: locking/core] lockdep: Fix usage_traceoverflow
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On Fri, Oct 30, 2020 at 10:38:06AM +0100, Peter Zijlstra wrote:
> >  		if (!chain_head && ret != 2) {
> >  			if (!check_prevs_add(curr, hlock))
> 
> I'm not entirely sure that doesn't still trigger the problem. Consider
> @chain_head := true.

Urgh, clearly my brain really isn't working well. Ignore that.