From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e28smtp04.in.ibm.com (e28smtp04.in.ibm.com [122.248.162.4]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp04.in.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id C71C01007DA for ; Thu, 16 Sep 2010 22:08:13 +1000 (EST) Received: from d28relay01.in.ibm.com (d28relay01.in.ibm.com [9.184.220.58]) by e28smtp04.in.ibm.com (8.14.4/8.13.1) with ESMTP id o8GC88dq023210 for ; Thu, 16 Sep 2010 17:38:08 +0530 Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) by d28relay01.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o8GC88Me4116486 for ; Thu, 16 Sep 2010 17:38:08 +0530 Received: from d28av03.in.ibm.com (loopback [127.0.0.1]) by d28av03.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o8GC87KM003514 for ; Thu, 16 Sep 2010 22:08:08 +1000 Date: Thu, 16 Sep 2010 17:38:06 +0530 From: Ankita Garg To: Benjamin Herrenschmidt Subject: Re: Reserved pages in PowerPC Message-ID: <20100916120806.GJ2332@in.ibm.com> References: <20100916052311.GC2332@in.ibm.com> <1284631464.30449.85.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1284631464.30449.85.camel@pasglop> Cc: linuxppc-dev@ozlabs.org, linux-mm@kvack.org Reply-To: Ankita Garg List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi Ben, On Thu, Sep 16, 2010 at 08:04:24PM +1000, Benjamin Herrenschmidt wrote: > On Thu, 2010-09-16 at 10:53 +0530, Ankita Garg wrote: > > > > With some debugging I found that that section has reserved pages. On > > instrumenting the memblock_reserve() and reserve_bootmem() routines, I can see > > that many of the memory areas are reserved for kernel and initrd by the > > memblock reserve() itself. reserve_bootmem then looks at the pages already > > reserved and marks them reserved. However, for the very last section, I see > > that bootmem reserves it but I am unable to find a corresponding reservation > > by the memblock code. > > It's probably RTAS (firmware runtime services). I'ts instanciated at > boot from prom_init and we do favor high addresses for it below 1G iirc. > Thanks Ben for taking a look at this. So I checked the rtas messages on the serial console and see the following: instantiating rtas at 0x000000000f632000... done Which does not correspond to the higher addresses that I see as reserved (observation on a 16G machine). -- Regards, Ankita Garg (ankita@in.ibm.com) Linux Technology Center IBM India Systems & Technology Labs, Bangalore, India