Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755985AbZF2XsQ (ORCPT ); Mon, 29 Jun 2009 19:48:16 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751680AbZF2XsC (ORCPT ); Mon, 29 Jun 2009 19:48:02 -0400 Received: from smtp-out.google.com ([216.239.45.13]:11321 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751486AbZF2XsA (ORCPT ); Mon, 29 Jun 2009 19:48:00 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=date:from:x-x-sender:to:cc:subject:in-reply-to:message-id: references:user-agent:mime-version:content-type:x-system-of-record; b=fBFFUBtTLunuZcBS8v3xYSE7W7okv7Gh6U9z+6uO8T3Exd/LioCp31G2Uf8RZSKXd AJXP67Iv9+a371kHW6CcA== Date: Mon, 29 Jun 2009 16:47:57 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Larry Finger cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Johannes Berg , Pekka Enberg , Christoph Lameter Subject: Re: [Bug #13319] Page allocation failures with b43 and p54usb In-Reply-To: <4A48F114.1010702@lwfinger.net> Message-ID: References: <5Hhc7UkUKEO.A.fNH.4kASKB@chimera> <4A48F114.1010702@lwfinger.net> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1616 Lines: 32 On Mon, 29 Jun 2009, Larry Finger wrote: > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13319 > > Subject : Page allocation failures with b43 and p54usb > > Submitter : Larry Finger > > Date : 2009-04-29 21:01 (61 days old) > > References : http://marc.info/?l=linux-kernel&m=124103897101088&w=4 > > http://lkml.org/lkml/2009/6/7/136 > > Handled-By : Johannes Berg > > The cause of these failures has been determined. The wireless > subsystem frequently requests buffers of size 4096, but when SLUB > debugging is enabled and the debug info is added, the request becomes > of order 1 and memory becomes fragmented. > > A controversial "fix" in which SLUB debugging was disabled for > allocations where adding such debugging info would increase the order > was discussed and tried. With a quick look at the commit list for > Linus's tree, I don't see that such a patch is available, but I will > be corrected if I missed it. > I'd disagree with disabling slub debugging by default for caches where oo_order(s->min) increases as the result of using it. This particular page allocation failure is happening for, presumably, kmalloc-4096, and the system has 4K pages. Disabling debugging for that cache (and any of its aliases) implicitly will lead to errors going undiagnosed as a result. -- 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/