From owner-svn-src-head@FreeBSD.ORG Mon Apr 13 15:24:11 2015 Return-Path: Delivered-To: svn-src-head@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id B0390675; Mon, 13 Apr 2015 15:24:11 +0000 (UTC) Received: from mail-wi0-x234.google.com (mail-wi0-x234.google.com [IPv6:2a00:1450:400c:c05::234]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 54959A64; Mon, 13 Apr 2015 15:24:11 +0000 (UTC) Received: by widdi4 with SMTP id di4so77544682wid.0; Mon, 13 Apr 2015 08:24:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=2ZZ1d/ecxlEhNdilBFRlbgtPHA2Z4um6meHoPPWAtHs=; b=zMae0p9AwINPYQRXb4Fh8o9mbSXE4l2q83HRdRYNoxfvC34Ed6KlSUxia4O4dBK/2u HCyLN6ZXXVdVAxAD7hmebj84Z6OgHjRN8iTAAIm01CBzn2vdMaNLi3YLg5zVBfAyq7aN 7afix48aZ+a/n3ntSQVQn+bRm8gz32QegSRd7sM4PuyrTlBYsxQqNs/2G4FRyLRt+EP1 bChf0KmGW36ECSH1wofJXZHezpKmOC3KDw2GJTyKz0vsWSr+zEVW9gw3h4wWBRlumWdR cE6f9Pz7C8iGFOmUC0vE9J5sBCxegMWDxk8ElxrnwwcCyw9jrnFyrZlpdB2RTg+0Ge0L K97w== MIME-Version: 1.0 X-Received: by 10.180.97.129 with SMTP id ea1mr23048875wib.24.1428938649706; Mon, 13 Apr 2015 08:24:09 -0700 (PDT) Received: by 10.27.77.201 with HTTP; Mon, 13 Apr 2015 08:24:09 -0700 (PDT) In-Reply-To: <201504131522.t3DFMkiE050257@svn.freebsd.org> References: <201504131522.t3DFMkiE050257@svn.freebsd.org> Date: Mon, 13 Apr 2015 11:24:09 -0400 Message-ID: Subject: Re: svn commit: r281495 - in head/sys: conf i386/i386 i386/include x86/acpica From: Benjamin Kaduk To: Konstantin Belousov Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.18-1 Cc: "svn-src-head@freebsd.org" , "svn-src-all@freebsd.org" , "src-committers@freebsd.org" X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 13 Apr 2015 15:24:11 -0000 On Mon, Apr 13, 2015 at 11:22 AM, Konstantin Belousov wrote: > Author: kib > Date: Mon Apr 13 15:22:45 2015 > New Revision: 281495 > URL: https://svnweb.freebsd.org/changeset/base/281495 > > Log: > Add config option PAE_TABLES for the i386 kernel. It switches pmap to > use PAE format for the page tables, but does not incur other > consequences of the full PAE config. In particular, vm_paddr_t and > bus_addr_t are left 32bit, and max supported memory is still limited > by 4GB. > > The option allows to have nx permissions for memory mappings on i386 > kernel, while keeping the usual i386 KBI and avoiding the kernel data > sizing problems typical for the PAE config. > > Intel documented that the PAE format for page tables is available > starting with the Pentium Pro, but it is possible that the plain > Pentium CPUs have the required support (Appendix H). The goal is to > enable the option and non-exec mappings on i386 for the GENERIC > kernel. Anybody wanting a useful system on 486, have to reconfigure > the modern i386 kernel anyway. > > Discussed with: alc, jhb > Sponsored by: The FreeBSD Foundation > MFC after: 2 weeks > relnotes: yes? -Ben