From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [RFC PATCH 1/3] asm-generic: io: Add exec versions of ioremap Date: Wed, 18 May 2016 21:57:59 +0100 Message-ID: <20160518205758.GY5783@n2100.arm.linux.org.uk> References: <1462830111-28172-1-git-send-email-d-gerlach@ti.com> <573C7844.5030107@ti.com> <20160518175102.GX5783@n2100.arm.linux.org.uk> <3861017.ZJOlWYvEFT@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <3861017.ZJOlWYvEFT@wuerfel> Sender: linux-kernel-owner@vger.kernel.org To: Arnd Bergmann Cc: Dave Gerlach , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, Russ Dill , Greg Kroah-Hartman , Shawn Guo , Tony Lindgren , Alexandre Belloni , Nishanth Menon List-Id: linux-omap@vger.kernel.org On Wed, May 18, 2016 at 10:25:03PM +0200, Arnd Bergmann wrote: > The ARM version of ioremap_exec() that gets added in this patch is cached > (like memremap()), but then the asm-generic version is not? This is > even more confusing, it should at least do roughly the same thing across > architectures. > > There should also be some documentation about what the expected behavior is, e.g.: > > - is memremap_exec() by default cached or not? (I assume it would > be like memremap()) > - If we have an interface that does explicit uncached executable mapping, > what about architectures on which this is not possible? Should they > fall back to cached or non-executable, or cause a link error? Another important point is whether atomic instructions / kernel locks can be located within the mapped memory. -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net.