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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS autolearn=ham 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 F1AB1C43441 for ; Wed, 14 Nov 2018 07:43:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BAD0221780 for ; Wed, 14 Nov 2018 07:43:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BAD0221780 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=dev.tdt.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730006AbeKNRpz (ORCPT ); Wed, 14 Nov 2018 12:45:55 -0500 Received: from ms.tdt.de ([195.243.126.94]:57849 "EHLO mail.dev.tdt.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725907AbeKNRpz (ORCPT ); Wed, 14 Nov 2018 12:45:55 -0500 Received: from mail.dev.tdt.de (localhost [IPv6:::1]) by mail.dev.tdt.de (Postfix) with ESMTP id C9083203C7; Wed, 14 Nov 2018 07:43:49 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 14 Nov 2018 08:43:49 +0100 From: Martin Schiller To: Andrew Lunn Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, f.fainelli@gmail.com, davem@davemloft.net Subject: Re: [PATCH v2] net: phy: mdio-gpio: fix access that may sleep Organization: TDT GmbH In-Reply-To: <20181114070528.GD17052@lunn.ch> References: <20181114061703.11026-1-ms@dev.tdt.de> <20181114063703.13379-1-ms@dev.tdt.de> <20181114070528.GD17052@lunn.ch> Message-ID: <248deac95f412b925b0de44ead2ffec6@dev.tdt.de> X-Sender: ms@dev.tdt.de User-Agent: Roundcube Webmail/1.1.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-11-14 08:05, Andrew Lunn wrote: > On Wed, Nov 14, 2018 at 07:37:03AM +0100, Martin Schiller wrote: >> This commit re-enables support for slow GPIO pins. It was initially >> introduced by commit >> 2d6c9091ab7630dfcf34417c6683ce4764d7d40a >> and got lost by commit >> 7e5fbd1e0700f1bdb94508f84ec2aeb01eed7b12 > > Hi Martin > > Was it really lost? It looks like _cansleep() just adds an extra check > might_sleep_if(extra_checks), but it does not change any > functionality. Well, you are right, the functionality itself is not broken, but using the NON _cansleep() functions on GPIOs that have the cansleep flag set, this leads to a lot of kernel warnings/backtraces which makes the system in fact useless. Thats the WARN_ON() here: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpio/gpiolib.c?h=v4.20-rc2#n2992 and here: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpio/gpiolib.c?h=v4.20-rc2#n3304 > > So the change itself is O.K, i'm just not too sure about the commit > message. > > Andrew Hmm, ok. What would you suggest for a better commit message? I thought it would be helpful to know that this was already in there and got (inadvertently?) removed by another commit. Martin