From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: lockdep: strange %s#5 lock name Date: Thu, 13 Feb 2014 17:15:15 -0500 Message-ID: <20140213221515.GL17608@htj.dyndns.org> References: <20140210192846.GF27965@twins.programming.kicks-ass.net> <20140210215224.GB25350@mtj.dyndns.org> <20140211110036.GT9987@twins.programming.kicks-ass.net> <20140211152741.GA24490@htj.dyndns.org> <1392266124.4974.35.camel@ThinkPad-T5421.cn.ibm.com> <20140213212645.GG17608@htj.dyndns.org> <20140213213253.GF27965@twins.programming.kicks-ass.net> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; bh=5kDLDzrWssgAyN81j8fYWlSvXHk7SEbDQ+NFIWf4IB8=; b=q546iKpPw7qP2lXWl0YyU2Tr9vZ1MgZmGCOGj+uAXYYyWa5wo0mUxZo15H80xmCcu6 EKvA/GV4iJJFNMO9nOfd75PuwHuBxTty1tCSGsfvP0m6fFAQgRvUhGNN21jedhEpQiFA YV9t7xxjxEWZH/1MY+85wNGCY9o9Zd+BNLu0JvRTO+M0o+p1E5zTxTT1Xb/sRrqH8h0W l+xAxojJKJ+xoRZ3yD3bBy8oO50oUi/NHc5nAs9waN7Uvt4mV9owPCW33JVCnZerwuCa Fwffxbza56f02Z7y4f5OCdghAx8mx76V1YhhCxHdEQ3zW2txuXi6orhJlgo/J/9oGqsh Ud4A== Content-Disposition: inline In-Reply-To: <20140213213253.GF27965@twins.programming.kicks-ass.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Peter Zijlstra Cc: Li Zhong , Tommi Rantala , Ingo Molnar , LKML , Dave Jones , trinity@vger.kernel.org On Thu, Feb 13, 2014 at 10:32:53PM +0100, Peter Zijlstra wrote: > On Thu, Feb 13, 2014 at 04:26:45PM -0500, Tejun Heo wrote: > > > It seems to me that when the second time alloc_workqueue() is called > > > from the same code path, it would have two locks with the same key, but > > > not the same &wq->name, which doesn't meet lockdep's assumption. > > > > Dang... I reverted the previous patch for now. Peter, does this > > approach sound good to you? > > Whatever works I suppose; like Li said; a little ugly but not sure we > can do better. Cool, Li, can you please spin it on top of v3.14-rc1 w/ SOB and description. Thanks. -- tejun