From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8FCAFC8300B for ; Thu, 30 Apr 2020 10:56:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6934720838 for ; Thu, 30 Apr 2020 10:56:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726884AbgD3K4V (ORCPT ); Thu, 30 Apr 2020 06:56:21 -0400 Received: from kernel.crashing.org ([76.164.61.194]:50512 "EHLO kernel.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725280AbgD3K4V (ORCPT ); Thu, 30 Apr 2020 06:56:21 -0400 Received: from localhost (gate.crashing.org [63.228.1.57]) (authenticated bits=0) by kernel.crashing.org (8.14.7/8.14.7) with ESMTP id 03UAtojD025184 (version=TLSv1/SSLv3 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 30 Apr 2020 05:55:54 -0500 Message-ID: <232b9fac588beb4d024ab496b118c51af2b0ecba.camel@kernel.crashing.org> Subject: Re: [PATCH v0 linux master] i2c/busses: Avoid i2c interrupt status clear race condition. From: Benjamin Herrenschmidt To: Wolfram Sang , Ryan Chen Cc: Brendan Higgins , Joel Stanley , Andrew Jeffery , "linux-i2c@vger.kernel.org" , "openbmc@lists.ozlabs.org" , "linux-arm-kernel@lists.infradead.org" , "linux-aspeed@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" Date: Thu, 30 Apr 2020 20:55:48 +1000 In-Reply-To: <20200429090355.GA2891@kunai> References: <20200429033737.2781-1-ryan_chen@aspeedtech.com> <20200429075357.GA1957@kunai> <56add9c6e6b5410986325a1360466e4b@TWMBX02.aspeed.com> <20200429090355.GA2891@kunai> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.28.5-0ubuntu0.18.04.2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2020-04-29 at 11:03 +0200, Wolfram Sang wrote: > > And is there maybe a Fixes: tag for it? > > [Ryan Chen] Yes it is a fix patch. > > I meant this (from submitting-patches.rst): It fixes the original implementation of the driver basically. It's just a classic posted-write fix. The write to clear the pending interrupt is asynchronous, so you can get spurrious ones if you return from the handler before it has percolated to the HW. I assume it's just more visible on the 2600 because of the cores are significantly faster but the IO bus is still as dumb. Ryan: You could always add a Fixed-by: tag that specifies the commit that added the initial driver... Cheers, Ben.