Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760519AbYCURmF (ORCPT ); Fri, 21 Mar 2008 13:42:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760105AbYCURlv (ORCPT ); Fri, 21 Mar 2008 13:41:51 -0400 Received: from relay1.sgi.com ([192.48.171.29]:48220 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1760061AbYCURlu (ORCPT ); Fri, 21 Mar 2008 13:41:50 -0400 Date: Fri, 21 Mar 2008 10:40:18 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: David Miller cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [11/14] vcompound: Fallbacks for order 1 stack allocations on IA64 and x86 In-Reply-To: <20080321.002502.223136918.davem@davemloft.net> Message-ID: References: <20080321061703.921169367@sgi.com> <20080321061726.782068299@sgi.com> <20080321.002502.223136918.davem@davemloft.net> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 786 Lines: 18 On Fri, 21 Mar 2008, David Miller wrote: > I would be very careful with this especially on IA64. > > If the TLB miss or other low-level trap handler depends upon being > able to dereference thread info, task struct, or kernel stack stuff > without causing a fault outside of the linear PAGE_OFFSET area, this > patch will cause problems. Hmmm. Does not sound good for arches that cannot handle TLB misses in hardware. I wonder how arch specific this is? Last time around I was told that some arches already virtually map their stacks. -- 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/