Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754513AbZGOLzk (ORCPT ); Wed, 15 Jul 2009 07:55:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754485AbZGOLzj (ORCPT ); Wed, 15 Jul 2009 07:55:39 -0400 Received: from mail-yx0-f184.google.com ([209.85.210.184]:45561 "EHLO mail-yx0-f184.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754482AbZGOLzj (ORCPT ); Wed, 15 Jul 2009 07:55:39 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; b=px1qTGTdGAsMld6hDAKvRFdg539os8TIOVemlgNCwQiZSMbIYKBLLJFc9eDzdfB9IS ZTe/X0sqYImciG43yQAc4IIJQSRxbjv9HRs098UtJaKgR6xYbyOrKRQnxs+ycJhFmhFP ks8aP3R3HHrq1LzctAZTv34JIR1xC6YtG+k/8= MIME-Version: 1.0 In-Reply-To: <2898.1247658300@redhat.com> References: <1247591665-12000-1-git-send-email-vapier@gentoo.org> <20090714161416.GA19147@cmpxchg.org> <6206.1247592126@redhat.com> <4A5CFFD8.7020106@t-online.de> <12377.1247654255@redhat.com> <8bd0f97a0907150412h234cf4d6l439d92d832055373@mail.gmail.com> <2898.1247658300@redhat.com> From: Mike Frysinger Date: Wed, 15 Jul 2009 07:55:18 -0400 Message-ID: <8bd0f97a0907150455l59a86540l655604579ab70b4f@mail.gmail.com> Subject: Re: [Uclinux-dist-devel] [PATCH v2] NOMMU: add support for Memory Protection Units (MPU) To: David Howells Cc: Bernd Schmidt , uclinux-dist-devel@blackfin.uclinux.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 727 Lines: 17 On Wed, Jul 15, 2009 at 07:45, David Howells wrote: > Mike Frysinger wrote: >> there is full 4k page protection between processes and between the >> kernel and processes. > > So you have a separate bitmap per process? yes, you can see page_rwx_mask in our mmu.h's mm_context_t. this is what the protect_page/update_protections operate on. we have a global current_rwx_mask that gets updated during context changes and the CPLB miss handler uses that to keep things simple. -mike -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/