From owner-cvs-all@FreeBSD.ORG Tue Dec 20 15:29:02 2005 Return-Path: X-Original-To: cvs-all@freebsd.org Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id ED2DF16A420; Tue, 20 Dec 2005 15:29:02 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from speedfactory.net (mail6.speedfactory.net [66.23.216.219]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0F05843D58; Tue, 20 Dec 2005 15:29:01 +0000 (GMT) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (unverified [66.23.211.162]) by speedfactory.net (SurgeMail 3.5b3) with ESMTP id 4212012 for multiple; Tue, 20 Dec 2005 10:27:05 -0500 Received: from localhost (john@localhost [127.0.0.1]) by server.baldwin.cx (8.13.4/8.13.4) with ESMTP id jBKFSsII006642; Tue, 20 Dec 2005 10:28:54 -0500 (EST) (envelope-from jhb@freebsd.org) From: John Baldwin To: Maxim.Sobolev@portaone.com Date: Tue, 20 Dec 2005 09:59:15 -0500 User-Agent: KMail/1.8.2 References: <200512190926.jBJ9QhbD078141@repoman.freebsd.org> <200512191420.03927.jhb@freebsd.org> <43A7895C.9060608@portaone.com> In-Reply-To: <43A7895C.9060608@portaone.com> MIME-Version: 1.0 Content-Type: text/plain; charset="koi8-u" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200512200959.16641.jhb@freebsd.org> X-Virus-Scanned: ClamAV version 0.87.1, clamav-milter version 0.87 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-1.4 required=4.2 tests=ALL_TRUSTED autolearn=failed version=3.1.0 X-Spam-Checker-Version: SpamAssassin 3.1.0 (2005-09-13) on server.baldwin.cx X-Server: High Performance Mail Server - http://surgemail.com r=1653887525 Cc: cvs-src@freebsd.org, src-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/boot/i386/loader main.c X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 Dec 2005 15:29:03 -0000 On Monday 19 December 2005 11:32 pm, Maxim Sobolev wrote: > John Baldwin wrote: > > On Monday 19 December 2005 01:32 pm, Maxim Sobolev wrote: > >> John Baldwin wrote: > >>> On Monday 19 December 2005 04:26 am, Maxim Sobolev wrote: > >>>> sobomax 2005-12-19 09:26:42 UTC > >>>> > >>>> FreeBSD src repository > >>>> > >>>> Modified files: > >>>> sys/boot/i386/loader main.c > >>>> Log: > >>>> If LOADER_BZIP2_SUPPORT is defined allocate heap in the 1MB-4MB > >>>> range to provide enough room for decompression (up to 2.5MB is > >>>> necessary). This should be safe to do since we load i386 kernels after > >>>> 8MB mark now, so that 16MB is the minimum amount of RAM necessary to > >>>> even boot FreeBSD. > >>> > >>> Err, I thought we loaded PAE kernels at 2MB and non-PAE kernels at 4MB > >>> to skip the first PSE page (PSE pages are 2MB on PAE). > >> > >> You are right, my mistake, sorry. In any case memory in the range > >> 1MB-4MB can be used by default. > > > > Errm, no it can't. PAE kernels (and amd64 kernels I think) are both > > loaded at 2MB, so that only leaves memory in the range 1MB-2MB. > > I see, did not know about amd64 (PAE is less a concern for me since it's > not a default kernel). What do you think about the following patch: > > http://www.pbxpress.com/~sobomax/loader.diff > > It moves heap to the top of the extended memory and teaches > i386_copyin() to avoid messing up this region, so that in low memory > situation it will just fail, not trash heap. So, if I understand correctly, you're now sticking the heap at the last 3MB of RAM. FYI, as long as you have a PPro or newer you can test booting a PAE kernel. You don't have to have > 4GB of RAM. So, you can test this locally to see if you can boot a PAE kernel (bzipped at that!) before committing. -- John Baldwin <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.org