From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760419AbXJDTeS (ORCPT ); Thu, 4 Oct 2007 15:34:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755796AbXJDTeJ (ORCPT ); Thu, 4 Oct 2007 15:34:09 -0400 Received: from netops-testserver-3-out.sgi.com ([192.48.171.28]:52003 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752018AbXJDTeI (ORCPT ); Thu, 4 Oct 2007 15:34:08 -0400 Date: Thu, 4 Oct 2007 12:34:07 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: David Miller cc: arjan@infradead.org, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, ak@suse.de, travis@sgi.com Subject: Re: [14/18] Configure stack size In-Reply-To: <20071003.214306.41634525.davem@davemloft.net> Message-ID: References: <20071004035935.042951211@sgi.com> <20071004040004.936534357@sgi.com> <20071003213631.7a047dde@laptopd505.fenrus.org> <20071003.214306.41634525.davem@davemloft.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 3 Oct 2007, David Miller wrote: > > there is still code that does DMA from and to the stack.... > > how would this work with virtual allocated stack? > > That's a bug and must be fixed. > > There honestly shouldn't be that many examples around. > > FWIW, there are platforms using a virtually allocated kernel stack > already. There would be a way to address this by checking in the DMA layer for a virtually mapped page and then segmenting I/O at the page boundaries to the individual pages. We may need that anyways for large block sizes.