From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752918AbaBVKW3 (ORCPT ); Sat, 22 Feb 2014 05:22:29 -0500 Received: from gw-1.arm.linux.org.uk ([78.32.30.217]:46765 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752498AbaBVKW2 (ORCPT ); Sat, 22 Feb 2014 05:22:28 -0500 Date: Sat, 22 Feb 2014 10:22:21 +0000 From: Russell King - ARM Linux To: Russ Dill Cc: Sebastian Capella , Lorenzo Pieralisi , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" , "linaro-kernel@lists.linaro.org" , "linux-arm-kernel@lists.infradead.org" , "Rafael J. Wysocki" , Len Brown , Pavel Machek , Nicolas Pitre , Santosh Shilimkar , Will Deacon , Jonathan Austin , Catalin Marinas , Uwe Kleine-K?nig , Stephen Boyd Subject: Re: [PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk Message-ID: <20140222102221.GF21483@n2100.arm.linux.org.uk> References: <1392774729-3235-1-git-send-email-sebastian.capella@linaro.org> <1392774729-3235-4-git-send-email-sebastian.capella@linaro.org> <20140219161254.GB19343@e102568-lin.cambridge.arm.com> <20140219193315.3732.21819@capellas-linux> <20140220162754.GC15994@e102568-lin.cambridge.arm.com> <20140221183956.29890.80931@capellas-linux> <20140221235911.14777.13919@capellas-linux> <20140222043714.19852.67450@capellas-linux> <530847E3.4070401@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <530847E3.4070401@ti.com> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 21, 2014 at 10:46:59PM -0800, Russ Dill wrote: > If there is worry about this, you could setup a page mapping in a > __nosave region, preventing it from being overwritten. Why would we need _another_ set of pages tables? Aren't two (swapper_pg_dir and the idmap one) enough? You do need to switch to the idmap one if you're going to call cpu_resume at its physical address, because that requires the identity mapping in order to work. -- FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up. Estimation in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad. Estimate before purchase was "up to 13.2Mbit". From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk Date: Sat, 22 Feb 2014 10:22:21 +0000 Message-ID: <20140222102221.GF21483@n2100.arm.linux.org.uk> References: <1392774729-3235-1-git-send-email-sebastian.capella@linaro.org> <1392774729-3235-4-git-send-email-sebastian.capella@linaro.org> <20140219161254.GB19343@e102568-lin.cambridge.arm.com> <20140219193315.3732.21819@capellas-linux> <20140220162754.GC15994@e102568-lin.cambridge.arm.com> <20140221183956.29890.80931@capellas-linux> <20140221235911.14777.13919@capellas-linux> <20140222043714.19852.67450@capellas-linux> <530847E3.4070401@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <530847E3.4070401@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: Russ Dill Cc: Sebastian Capella , Lorenzo Pieralisi , "linux-kernel@vger.kernel.org" , "linux-pm@vger.kernel.org" , "linaro-kernel@lists.linaro.org" , "linux-arm-kernel@lists.infradead.org" , "Rafael J. Wysocki" , Len Brown , Pavel Machek , Nicolas Pitre , Santosh Shilimkar , Will Deacon , Jonathan Austin , Catalin Marinas , Uwe Kleine-K?nig , Stephen Boyd List-Id: linux-pm@vger.kernel.org On Fri, Feb 21, 2014 at 10:46:59PM -0800, Russ Dill wrote: > If there is worry about this, you could setup a page mapping in a > __nosave region, preventing it from being overwritten. Why would we need _another_ set of pages tables? Aren't two (swapper_pg_dir and the idmap one) enough? You do need to switch to the idmap one if you're going to call cpu_resume at its physical address, because that requires the identity mapping in order to work. -- FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up. Estimation in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad. Estimate before purchase was "up to 13.2Mbit". From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@arm.linux.org.uk (Russell King - ARM Linux) Date: Sat, 22 Feb 2014 10:22:21 +0000 Subject: [PATCH RFC v1 3/3] ARM hibernation / suspend-to-disk In-Reply-To: <530847E3.4070401@ti.com> References: <1392774729-3235-1-git-send-email-sebastian.capella@linaro.org> <1392774729-3235-4-git-send-email-sebastian.capella@linaro.org> <20140219161254.GB19343@e102568-lin.cambridge.arm.com> <20140219193315.3732.21819@capellas-linux> <20140220162754.GC15994@e102568-lin.cambridge.arm.com> <20140221183956.29890.80931@capellas-linux> <20140221235911.14777.13919@capellas-linux> <20140222043714.19852.67450@capellas-linux> <530847E3.4070401@ti.com> Message-ID: <20140222102221.GF21483@n2100.arm.linux.org.uk> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, Feb 21, 2014 at 10:46:59PM -0800, Russ Dill wrote: > If there is worry about this, you could setup a page mapping in a > __nosave region, preventing it from being overwritten. Why would we need _another_ set of pages tables? Aren't two (swapper_pg_dir and the idmap one) enough? You do need to switch to the idmap one if you're going to call cpu_resume at its physical address, because that requires the identity mapping in order to work. -- FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up. Estimation in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad. Estimate before purchase was "up to 13.2Mbit".