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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9FEF2C433FF for ; Thu, 1 Aug 2019 22:05:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7974B2080C for ; Thu, 1 Aug 2019 22:05:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389336AbfHAWFP (ORCPT ); Thu, 1 Aug 2019 18:05:15 -0400 Received: from hosting.gsystem.sk ([212.5.213.30]:59192 "EHLO hosting.gsystem.sk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727987AbfHAWFP (ORCPT ); Thu, 1 Aug 2019 18:05:15 -0400 X-Greylist: delayed 396 seconds by postgrey-1.27 at vger.kernel.org; Thu, 01 Aug 2019 18:05:14 EDT Received: from [192.168.0.2] (188-167-68-178.dynamic.chello.sk [188.167.68.178]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by hosting.gsystem.sk (Postfix) with ESMTPSA id 043817A0215; Thu, 1 Aug 2019 23:58:37 +0200 (CEST) From: Ondrej Zary To: Guenter Roeck Subject: Re: Marking legacy watchdog drivers as deprecated / obsolete Date: Thu, 1 Aug 2019 23:58:34 +0200 User-Agent: KMail/1.9.10 Cc: Arnd Bergmann , linux-watchdog@cger.kernel.org, Wim Van Sebroeck , Linux Kernel Mailing List References: <20190729220720.GB5712@roeck-us.net> <20190730155737.GA22593@roeck-us.net> In-Reply-To: <20190730155737.GA22593@roeck-us.net> X-KMail-QuotePrefix: > MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <201908012358.34991.linux@zary.sk> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 30 July 2019 17:57:37 Guenter Roeck wrote: > On Tue, Jul 30, 2019 at 10:00:36AM +0200, Arnd Bergmann wrote: > > On Tue, Jul 30, 2019 at 12:07 AM Guenter Roeck wrote: > > > > > > Hi, > > > > > > we have recently seen a number of changes to legacy watchdog drivers, > > > mostly surrounding the coding style used some 10+ years ago, but also > > > fixing minor formatting or coding problems found by static analyzers. > > > This slowly rises above the level of background noise. > > > > > > Would it be acceptable to mark all those drivers as deprecated/obsolete, > > > warn users that the driver should be converted to use the watchdog > > > subsystem, and that it will otherwise be removed in a later Linux kernel > > > version ? This would give us an idea which drivers are still in use, > > > and it would enable us to remove the remaining drivers maybe 5 or 6 > > > releases for now. > > > > > > Thoughts ? > > > > I don't think an automated approach across 61 drivers is likely to work > > well. About half of the drivers appear to be for specific SoCs, and > > removing the watchdog driver while keeping the rest of the SoC support > > would not be helpful, it just means we break one of the drivers for the > > last remaining users of an old SoC the next time they try to upgrade to > > a new kernel. > > > > The primary goal would be to identify drivers still in use, and to trigger > efforts to convert those drivers to the new infrastructure. Removal of > obsolete / unused drivers would be a separate decision, to be made at some > point in the future, and individually for each driver. I specifically wasn't > trying to suggest auto-removal. > > Guenter > > > It would probably be helpful to go through the list and see if any of > > the drivers > > are for platforms that are already gone. FWIW, here is the list of drivers that > > have their own .ioctl() method, taken from a patch I'm sending soon > > to add a .compat_ioctl handler: > > > > arch/powerpc/platforms/52xx/mpc52xx_gpt.c > > arch/um/drivers/harddog_kern.c > > drivers/char/ipmi/ipmi_watchdog.c > > drivers/hwmon/fschmd.c > > drivers/rtc/rtc-ds1374.c > > drivers/watchdog/acquirewdt.c > > drivers/watchdog/advantechwdt.c > > drivers/watchdog/alim1535_wdt.c > > drivers/watchdog/alim7101_wdt.c > > drivers/watchdog/ar7_wdt.c > > drivers/watchdog/at91rm9200_wdt.c > > drivers/watchdog/ath79_wdt.c > > drivers/watchdog/bcm63xx_wdt.c > > drivers/watchdog/cpu5wdt.c > > drivers/watchdog/eurotechwdt.c > > drivers/watchdog/f71808e_wdt.c > > drivers/watchdog/gef_wdt.c > > drivers/watchdog/geodewdt.c > > drivers/watchdog/ib700wdt.c > > drivers/watchdog/ibmasr.c > > drivers/watchdog/indydog.c > > drivers/watchdog/intel_scu_watchdog.c > > drivers/watchdog/iop_wdt.c > > drivers/watchdog/it8712f_wdt.c > > drivers/watchdog/ixp4xx_wdt.c > > drivers/watchdog/ks8695_wdt.c > > drivers/watchdog/m54xx_wdt.c > > drivers/watchdog/machzwd.c > > drivers/watchdog/mixcomwd.c > > drivers/watchdog/mtx-1_wdt.c > > drivers/watchdog/mv64x60_wdt.c > > drivers/watchdog/nuc900_wdt.c > > drivers/watchdog/nv_tco.c > > drivers/watchdog/pc87413_wdt.c > > drivers/watchdog/pcwd.c > > drivers/watchdog/pcwd_pci.c > > drivers/watchdog/pcwd_usb.c > > drivers/watchdog/pika_wdt.c > > drivers/watchdog/pnx833x_wdt.c > > drivers/watchdog/rc32434_wdt.c > > drivers/watchdog/rdc321x_wdt.c > > drivers/watchdog/riowd.c > > drivers/watchdog/sa1100_wdt.c > > drivers/watchdog/sb_wdog.c > > drivers/watchdog/sbc60xxwdt.c > > drivers/watchdog/sbc7240_wdt.c > > drivers/watchdog/sbc_epx_c3.c > > drivers/watchdog/sbc_fitpc2_wdt.c > > drivers/watchdog/sc1200wdt.c > > drivers/watchdog/sc520_wdt.c > > drivers/watchdog/sch311x_wdt.c > > drivers/watchdog/scx200_wdt.c > > drivers/watchdog/smsc37b787_wdt.c > > drivers/watchdog/w83877f_wdt.c > > drivers/watchdog/w83977f_wdt.c > > drivers/watchdog/wafer5823wdt.c > > drivers/watchdog/wdrtas.c > > drivers/watchdog/wdt.c > > drivers/watchdog/wdt285.c > > drivers/watchdog/wdt977.c > > drivers/watchdog/wdt_pci.c > > > > Arnd > I have some older x86 boards so I probably could test some of them. Likely ALi chipset (alim1535_wdt.c and/or alim7101_wdt.c) and some super I/Os (it8712f_wdt.c, w83877f_wdt.c, w83977f_wdt.c). -- Ondrej Zary