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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 23DB5C43387 for ; Sun, 30 Dec 2018 17:52:17 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 48BD720861 for ; Sun, 30 Dec 2018 17:52:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 48BD720861 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=c-s.fr Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43SSgx5BMPzDqJR for ; Mon, 31 Dec 2018 04:52:13 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=c-s.fr Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=c-s.fr (client-ip=93.17.236.30; helo=pegase1.c-s.fr; envelope-from=christophe.leroy@c-s.fr; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=c-s.fr Received: from pegase1.c-s.fr (pegase1.c-s.fr [93.17.236.30]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 43SSdc6NGlzDqHL for ; Mon, 31 Dec 2018 04:50:11 +1100 (AEDT) Received: from localhost (mailhub1-int [192.168.12.234]) by localhost (Postfix) with ESMTP id 43SSdN6dZBz9tyyM; Sun, 30 Dec 2018 18:50:00 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at c-s.fr Received: from pegase1.c-s.fr ([192.168.12.234]) by localhost (pegase1.c-s.fr [192.168.12.234]) (amavisd-new, port 10024) with ESMTP id IFlTTtuyCB7x; Sun, 30 Dec 2018 18:50:00 +0100 (CET) Received: from vm-hermes.si.c-s.fr (vm-hermes.si.c-s.fr [192.168.25.253]) by pegase1.c-s.fr (Postfix) with ESMTP id 43SSdN61zsz9tyyL; Sun, 30 Dec 2018 18:50:00 +0100 (CET) Received: by vm-hermes.si.c-s.fr (Postfix, from userid 33) id 57EE11CB; Sun, 30 Dec 2018 18:50:02 +0100 (CET) Received: from 37-165-14-176.coucou-networks.fr (37-165-14-176.coucou-networks.fr [37.165.14.176]) by messagerie.si.c-s.fr (Horde Framework) with HTTP; Sun, 30 Dec 2018 18:50:02 +0100 Date: Sun, 30 Dec 2018 18:50:02 +0100 Message-ID: <20181230185002.Horde.AdSknvcs4hP1Kh_T_Cos6w8@messagerie.si.c-s.fr> From: LEROY Christophe To: Arnd Bergmann Subject: Re: [PATCH v8 01/25] scsi/atari_scsi: Don't select CONFIG_NVRAM References: <20181228173846.Horde.z_zDEJN0rVd8tkt3HjYzmg2@messagerie.si.c-s.fr>

<5e901432-65e2-c87b-31e3-36a394687a9a@gmail.com> In-Reply-To: User-Agent: Internet Messaging Program (IMP) H5 (6.2.3) Content-Type: text/plain; charset=UTF-8; format=flowed; DelSp=Yes MIME-Version: 1.0 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Schmitz , "James E.J. Bottomley" , linux-scsi , "Martin K. Petersen" , Greg Kroah-Hartman , Linux Kernel Mailing List , Finn Thain , linux-m68k , linuxppc-dev Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" Arnd Bergmann a =C3=A9crit=C2=A0: > On Sat, Dec 29, 2018 at 3:51 AM Michael Schmitz wr= ote: >> >> Hi Finn, >> >> Am 29.12.2018 um 15:34 schrieb Finn Thain: >> > On Sat, 29 Dec 2018, Michael Schmitz wrote: >> > >> >> >> >> IS_BUILTIN(CONFIG_NVRAM) is probably what Christophe really=20=20 >>=20meant to suggest. >> >> >> >> Or (really going out on a limb here): >> >> >> >> IS_BUILTIN(CONFIG_NVRAM) || >> >> ( IS_MODULE(CONFIG_ATARI_SCSI) && IS_ENABLED(CONFIG_NVRAM) ) >> >> >> >> Not that I'd advocate that, for this series. >> >> >> > >> > Well, you are a maintainer for atari_scsi.c. >> > >> > Are you saying that you want IS_BUILTIN(CONFIG_NVRAM) used here instea= d of >> > ifdef? >> >> No, just pointing out that there would be a way to avoid the ifdef >> without messing up driver behaviour. I'm fine with the ifdef - not least >> because it clearly eliminates code that would be unreachable. >> >> (On second thought - I don't want to speculate whether there's weird >> compiler options that could result in the nvram_check_checksum and >> nvram_read_bytes symbols to still be referenced in the final link, even >> though IS_BUILTIN(CONFIG_NVRAM) always evaluates to false. Best leave >> this as-is.) > > As far as I know, it's totally reliable with the supported compilers=20= =20 >=20(gcc-4.6+). > In the older compilers (e.g. 4.1), there was a corner case, where it coul= d > have failed to eliminate a function that was only referenced through=20= =20 >=20a pointer > from a discarded variable, but a plain IS_ENABLED() check like the one he= re > was still ok, and lots of code relies on that. > > Other than that, I agree either way is totally fine here, so no objection= s > to using the #ifdef. As far as I know, kernel codying style promotes the use of=20=20 IS_ENABLED()=20etc. instead of #ifdefs when possible. Christophe > > Arnd