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[209.132.180.67]) by mx.google.com with ESMTP id i61-v6si9368818plb.209.2018.08.31.02.57.36; Fri, 31 Aug 2018 02:57:51 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727874AbeHaOAU (ORCPT + 99 others); Fri, 31 Aug 2018 10:00:20 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:55438 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726493AbeHaOAU (ORCPT ); Fri, 31 Aug 2018 10:00:20 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1285918A; Fri, 31 Aug 2018 02:53:39 -0700 (PDT) Received: from edgewater-inn.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id D75673F721; Fri, 31 Aug 2018 02:53:38 -0700 (PDT) Received: by edgewater-inn.cambridge.arm.com (Postfix, from userid 1000) id 7288B1AE3614; Fri, 31 Aug 2018 10:53:51 +0100 (BST) Date: Fri, 31 Aug 2018 10:53:51 +0100 From: Will Deacon To: Vineet Gupta Cc: Peter Zijlstra , Eugeniy Paltsev , "mingo@kernel.org" , "linux-kernel@vger.kernel.org" , "Alexey.Brodkin@synopsys.com" , "tglx@linutronix.de" , "linux-snps-arc@lists.infradead.org" , "yamada.masahiro@socionext.com" , "linux-arm-kernel@lists.infradead.org" , "linux-arch@vger.kernel.org" Subject: Re: Patch "asm-generic/bitops/lock.h: Rewrite using atomic_fetch_" causes kernel crash Message-ID: <20180831095351.GD13166@arm.com> References: <20180830094411.GX24124@hirez.programming.kicks-ass.net> <20180830095148.GB5942@arm.com> <1535629996.4465.44.camel@synopsys.com> <20180830141713.GN24082@hirez.programming.kicks-ass.net> <20180830142354.GB13005@arm.com> <20180830142920.GO24082@hirez.programming.kicks-ass.net> <20180830204515.GC24124@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Aug 31, 2018 at 12:30:50AM +0000, Vineet Gupta wrote: > On 08/30/2018 01:45 PM, Peter Zijlstra wrote: > >> > >> Indeed this is the mother of all issues, I tried and system is clearly hosed with > >> and works after. > >> What's amazing is the commit 4aef66c8ae9 which introduced it is from 2016 ;-) > >> Back then we had a retry branch with backoff stuff which I'd reverted for new > >> cores and the merge conflict somehow missed it. > >> > >> @PeterZ I'll create a patch with you as author ? do I need any formal sign offs, > >> acks etc ? > > Well, Will spotted it, give authorship to him, you have my ack per the > > above. > > Oops, sorry for the mixup. I have him as author now and pushed to ARC for-curr > (will trickle into linux-next eventually). Okey doke: you can have my Signed-off-by for all the diffs I sent. Just stick something like [vineet: wrote commit message] in there so I don't read it in the future and confuse myself. Will