Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757229AbYCaS7S (ORCPT ); Mon, 31 Mar 2008 14:59:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754359AbYCaS7D (ORCPT ); Mon, 31 Mar 2008 14:59:03 -0400 Received: from relay1.sgi.com ([192.48.171.29]:33112 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754126AbYCaS7C (ORCPT ); Mon, 31 Mar 2008 14:59:02 -0400 Date: Mon, 31 Mar 2008 11:56:39 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Pekka Enberg cc: Linus Torvalds , "Rafael J. Wysocki" , Pawel Staszewski , LKML , Adrian Bunk , Andrew Morton , Natalie Protasevich Subject: Re: 2.6.25-rc7-git2: Reported regressions from 2.6.24 In-Reply-To: <84144f020803291652l13d3de82o424e126655b86119@mail.gmail.com> Message-ID: References: <200803272353.51901.rjw@sisk.pl> <84144f020803291652l13d3de82o424e126655b86119@mail.gmail.com> 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: 920 Lines: 19 On Sun, 30 Mar 2008, Pekka Enberg wrote: > Christoph, I think you're overlooking the same thing I was until Linus > straightened me out. We're calling kmalloc_large() from __slab_alloc() > for the fall-back case which causes a bug fixed by Linus' revert. Yes, that means that __GFP_ZERO can be passed to the page allocator there. Same thing as happens when kmalloc() calls kmalloc_large() (as you pointed out before). The harm is zeroing an allocated object twice in rare cases that trigger the fallback path and that is avoided by Linus' patch. For the fix to get rid of the backtraces that started this discussion see commit 9c312058b2e530722c7bd30c1b6f26eea35dc5fe -- 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/