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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 AF3BBC433E0 for ; Fri, 10 Jul 2020 05:39:12 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 7C7ED2072E for ; Fri, 10 Jul 2020 05:39:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="EfbPGgbE"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ODGTiXiS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7C7ED2072E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=JUpGnSvEyvkoD6wBr1HmQiKd5GGnDeBV+MaHhY8PuCk=; b=EfbPGgbE5V0IAGBfUbs1EoM5z ImWYKyYYggPUpLVou/MGUGxDgdAYcBDU061SDaJbaxFFpOboD29/pTw34PTjjRS9bgYSda5G4hxsR 0Yw8nh2plFVhr7D69EbzwBcO9J7rgLqCi0Rb7WColktQPWRPTCn3jhLqROgj2hOlylpN7x3MUvynT FdAfwXnvzsDkGKxnXht06HMqr72uLNdCpUFckPf+VQn0rfFCfU5kN9LNYnGWopxTgnXVhf+6j9uh5 1CZzPtA25y+IWO2iNR9g6YUdl55lD59ZEHyhUFVgarSUQU03E/p9x6gzlu43Zt6+cOA17aP6UAD9J 4u7Cvx0dQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jtlkW-0008HE-TL; Fri, 10 Jul 2020 05:39:04 +0000 Received: from casper.infradead.org ([2001:8b0:10b:1236::1]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jtlkV-0008Gy-0d; Fri, 10 Jul 2020 05:39:03 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=r8XAt9mvgsXI1HPZ95IOzogzdV+W6uZ7vWhIwgo9PM8=; b=ODGTiXiSnX6UuOzsheQ9KWKhON Lv6biMNVFXU5Cm2xqfDIjVinsSurMlb2w8kMD1JvdVTsea/lPxMxd6awgEAwpTUSvUoj+MX2rr7c0 YdIYC4Te0yCxbXu4bw2AaN/kbthRMvP8Aq4+l14lBnUVnpcS87tOTm2wgSK+fuzW3uNPWwT9+VOiL oLENoEMF0XoyxfE1aSOOiqnsfkNd5ND5OmUzfl0dmdSXs6w5pr112LsQcqW/Ev1742bUn61zi+yHR YhME47LV9DIBs7cTlPapnfctfHlcg2Co3xgEoyXoRRzXDvYo91geeGB7iU+OMYOb7YZg3pdGXxHH0 SsN0FNgg==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jtlkI-0007Co-Tn; Fri, 10 Jul 2020 05:38:50 +0000 Date: Fri, 10 Jul 2020 06:38:50 +0100 From: Christoph Hellwig To: Mike Rapoport Subject: Re: [PATCH 1/5] lib: Add a generic version of devmem_is_allowed() Message-ID: <20200710053850.GA27019@infradead.org> References: <20200709200552.1910298-1-palmer@dabbelt.com> <20200709200552.1910298-2-palmer@dabbelt.com> <20200709204921.GJ781326@linux.ibm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200709204921.GJ781326@linux.ibm.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, steve@sk2.org, gregory.0xf0@gmail.com, catalin.marinas@arm.com, linus.walleij@linaro.org, Palmer Dabbelt , zaslonko@linux.ibm.com, glider@google.com, krzk@kernel.org, zong.li@sifive.com, mchehab+samsung@kernel.org, linux-riscv@lists.infradead.org, alex.shi@linux.alibaba.com, will@kernel.org, ardb@kernel.org, linux-arch@vger.kernel.org, paulmck@kernel.org, alex@ghiti.fr, bgolaszewski@baylibre.com, masahiroy@kernel.org, linux@armlinux.org.uk, willy@infradead.org, takahiro.akashi@linaro.org, james.morse@arm.com, kernel-team@android.com, Arnd Bergmann , pmladek@suse.com, elver@google.com, aou@eecs.berkeley.edu, keescook@chromium.org, uwe@kleine-koenig.org, rostedt@goodmis.org, broonie@kernel.org, davidgow@google.com, Paul Walmsley , dan.j.williams@intel.com, andriy.shevchenko@linux.intel.com, gxt@pku.edu.cn, linux-arm-kernel@lists.infradead.org, Nick Desaulniers , tglx@linutronix.de, rdunlap@infradead.org, matti.vaittinen@fi.rohmeurope.com, linux-kernel@vger.kernel.org, mcgrof@kernel.org, Palmer Dabbelt , mhiramat@kernel.org, akpm@linux-foundation.org, davem@davemloft.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Thu, Jul 09, 2020 at 11:49:21PM +0300, Mike Rapoport wrote: > > +#ifndef CONFIG_GENERIC_DEVMEM_IS_ALLOWED > > +extern int devmem_is_allowed(unsigned long pfn); > > +#endif Nit: no need for the extern here. > > +config GENERIC_LIB_DEVMEM_IS_ALLOWED > > + bool > > + select ARCH_HAS_DEVMEM_IS_ALLOWED > > This seems to work the other way around from the usual Kconfig chains. > In the most cases ARCH_HAS_SOMETHING selects GENERIC_SOMETHING. > > I believe nicer way would be to make > > config STRICT_DEVMEM > bool "Filter access to /dev/mem" > depends on MMU && DEVMEM > depends on ARCH_HAS_DEVMEM_IS_ALLOWED || GENERIC_LIB_DEVMEM_IS_ALLOWED > > config GENERIC_LIB_DEVMEM_IS_ALLOWED > bool > > and then s/select ARCH_HAS_DEVMEM_IS_ALLOWED/select GENERIC_LIB_DEVMEM_IS_ALLOWED/ > in the arch Kconfigs and drop ARCH_HAS_DEVMEM_IS_ALLOWED in the end. To take a step back: Is there any reason to not just always STRICT_DEVMEM? Maybe for a few architectures that don't currently support a strict /dev/mem the generic version isn't quite correct, but someone selecting the option and finding the issue is the best way to figure that out.. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv