From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Hilman Subject: Re: [PATCH 08/13] OMAP3: PM: Deny MPU idle while saving secure RAM Date: Fri, 19 Nov 2010 13:09:36 -0800 Message-ID: <87sjyx2f73.fsf@deeprootsystems.com> References: <1290131698-6194-1-git-send-email-nm@ti.com> <1290131698-6194-9-git-send-email-nm@ti.com> <87eiahckba.fsf@deeprootsystems.com> <9f54a2ec7fc8c27fc57c2aac9bad5405@mail.gmail.com> <4CE6B2D4.1030201@ti.com> <7ae7a7b138d09fc819e16f213e81d3bd@mail.gmail.com> <877hg9ayox.fsf@deeprootsystems.com> <4CE6DB9E.9000708@ti.com> <87y68p3uee.fsf@deeprootsystems.com> <4CE6E5CE.7010502@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-yx0-f174.google.com ([209.85.213.174]:36108 "EHLO mail-yx0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756816Ab0KSVJk (ORCPT ); Fri, 19 Nov 2010 16:09:40 -0500 Received: by yxf34 with SMTP id 34so3010133yxf.19 for ; Fri, 19 Nov 2010 13:09:40 -0800 (PST) In-Reply-To: <4CE6E5CE.7010502@ti.com> (Nishanth Menon's message of "Fri, 19 Nov 2010 15:02:06 -0600") Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Nishanth Menon Cc: Santosh Shilimkar , linux-omap , Jean Pihet , Vishwanath Sripathy , Tony Nishanth Menon writes: > Kevin Hilman had written, on 11/19/2010 02:55 PM, the following: > [...] >> Now, based on what you say below, it seems like there is no way to >> guarantee that SMIs don't do this, so I guess we have no choice but to >> protect them all. > In that way, I do like the patch from Santosh - with the relevant > changes we will need to incorporate. Do keep in mind that SMI is a > secure service - In theory, there could be(and to my knowledge, are) > custom secure services to do all kind of other things that are not > power management related[1] - All the more reason that this secure mode code should be moved out of the core idle path into its own driver. Kevin > The only area we can protect is the one in idle/ power paths.