From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752371AbcJDGuV (ORCPT ); Tue, 4 Oct 2016 02:50:21 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:47862 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751469AbcJDGuU (ORCPT ); Tue, 4 Oct 2016 02:50:20 -0400 Date: Tue, 4 Oct 2016 08:50:15 +0200 From: Peter Zijlstra To: bdegraaf@codeaurora.org Cc: Mark Rutland , Ingo Molnar , Catalin Marinas , Will Deacon , Timur Tabi , Nathan Lynch , linux-kernel@vger.kernel.org, Christopher Covington , linux-arm-kernel@lists.infradead.org Subject: Re: [RFC] arm64: Enforce observed order for spinlock and data Message-ID: <20161004065015.GK3318@worktop.controleur.wifipass.org> References: <1475257257-23072-1-git-send-email-bdegraaf@codeaurora.org> <20160930193231.GA2521@remoulade> <66a031ac2405e352ab0d5f19d7ddb8e9@codeaurora.org> <20161001181101.GA17554@remoulade> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 03, 2016 at 03:20:57PM -0400, bdegraaf@codeaurora.org wrote: > Thinking about this, as the reader/writer code has no known "abuse" > case, I'll remove it from the patchset, then provide a v2 patchset > with a detailed explanation for the lockref problem using the commits > you provided as an example, as well as performance consideration. Please, fix lockref in those patches. Touching the spinlock because lockref does something dubious really is the wrong thing.