From patchwork Thu Jan 9 10:02:38 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell King - ARM Linux X-Patchwork-Id: 3458121 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 6ECB99F39F for ; Thu, 9 Jan 2014 10:03:36 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id BF47A20123 for ; Thu, 9 Jan 2014 10:03:31 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 7571420121 for ; Thu, 9 Jan 2014 10:03:30 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W1CST-0004Ma-96; Thu, 09 Jan 2014 10:03:25 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1W1CSQ-0007DU-Jh; Thu, 09 Jan 2014 10:03:22 +0000 Received: from pandora.arm.linux.org.uk ([2001:4d48:ad52:3201:214:fdff:fe10:1be6]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W1CSN-0007BB-8h for linux-arm-kernel@lists.infradead.org; Thu, 09 Jan 2014 10:03:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=arm.linux.org.uk; s=pandora; h=Sender:In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date; bh=0hEeQq+KjPfRDf0Qv2ZCHFPDyQtefVZHAVGR9dn6ECg=; b=WIGngSl/T/4p2C1kqspYbY66//+SNfF5vDd8pUrT6mWqoGQMYr6F6ZajLuCAyk3UZy4Mwg5b2U1noiyemUV4ewntfB3aLbsm9cBJGtd0/eb5XDeMdnt5eNRKSR5xLuoO8O7SPHebaoO/1nN6zdYjVST8dT5XHXlzPPRdUb6PW9s=; Received: from n2100.arm.linux.org.uk ([2002:4e20:1eda:1:214:fdff:fe10:4f86]:39968) by pandora.arm.linux.org.uk with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.76) (envelope-from ) id 1W1CRq-0003QP-3W; Thu, 09 Jan 2014 10:02:46 +0000 Received: from linux by n2100.arm.linux.org.uk with local (Exim 4.76) (envelope-from ) id 1W1CRm-0006ha-Cz; Thu, 09 Jan 2014 10:02:42 +0000 Date: Thu, 9 Jan 2014 10:02:38 +0000 From: Russell King - ARM Linux To: panchaxari Subject: Re: [PATCH CFT] ARM:REALVIEW: Enable AUTO_ZRELADDR by default Message-ID: <20140109100238.GW27432@n2100.arm.linux.org.uk> References: <1389242654-3925-1-git-send-email-panchaxari.prasannamurthy@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1389242654-3925-1-git-send-email-panchaxari.prasannamurthy@linaro.org> User-Agent: Mutt/1.5.19 (2009-01-05) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140109_050319_800240_8B01965E X-CRM114-Status: GOOD ( 13.45 ) X-Spam-Score: -2.0 (--) Cc: linaro-kernel@lists.linaro.org, Pawel Moll , patches@linaro.org, Linus Walleij , Will Deacon , linux-kernel@vger.kernel.org, Rob Herring , viresh.linux@gmail.com, Olof Johansson , Shawn Guo , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,RP_MATCHES_RCVD,T_DKIM_INVALID,UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Thu, Jan 09, 2014 at 10:14:14AM +0530, panchaxari wrote: > Below lkml link is a quoting by Russell, which explains more on concept of > PHYS_VIRT and ZRELADDR > ------------------------------------------------- > > https://lkml.org/lkml/2011/10/14/434 > > ------------------------------------------------- Okay, so you're just going around changing stuff, basing it on an old mail, and not testing the results of it. Stop this please. Note that the result of the above email was this: commit c1becedc8871645278832fabdc6fe138082a495b Author: Russell King Date: Wed Aug 10 10:23:45 2011 +0100 ARM: enable ARM_PATCH_PHYS_VIRT by default Enable virtual to physical translation patching by default in all kernels. Hide the option behind EMBEDDED. This can still be turned off if people desire, and they know what they're doing, to shrink the size of the kernel to a minimum. Acked-by: Will Deacon Signed-off-by: Russell King you get the chance to manually disable it. In fact, all those select ARM_PATCH_PHYS_VIRT are wrong, and add reverse dependencies that make maintanence of the Kconfig harder. I'd rather kill all those select statements rather than introduce yet more of them. Hence, all your recent patches adding "select ARM_PATCH_PHYS_VIRT" I say a very strong NAK to. diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 5ebc5d922ea1..8882a535cf44 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -195,7 +195,8 @@ config VECTORS_BASE The base address of exception vectors. config ARM_PATCH_PHYS_VIRT - bool "Patch physical to virtual translations at runtime" + bool "Patch physical to virtual translations at runtime" if EMBEDDED + default y depends on !XIP_KERNEL && MMU depends on !ARCH_REALVIEW || !SPARSEMEM help @@ -207,6 +208,10 @@ config ARM_PATCH_PHYS_VIRT of physical memory is at a 16MB boundary, or theoretically 64K for the MSM machine class. + Only disable this option if you know that you do not require + this feature (eg, building a kernel for a single machine) and + you need to shrink the kernel to the minimal size. which means that ARM_PATCH_PHYS_VIRT is enabled for virtually everything unless you decide that you want to enable EMBEDDED mode, in which case