From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752429Ab1EPH7k (ORCPT ); Mon, 16 May 2011 03:59:40 -0400 Received: from e38.co.us.ibm.com ([32.97.110.159]:56018 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752277Ab1EPH7j (ORCPT ); Mon, 16 May 2011 03:59:39 -0400 Date: Mon, 16 May 2011 00:59:26 -0700 From: Ram Pai To: Yinghai Lu Cc: Jesse Barnes , Linus Torvalds , "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" , Andrew Morton , Bjorn Helgaas Subject: Re: [PATCH -v2] pci: Check bridge resources after resource allocation. Message-ID: <20110516075926.GW8195@ram-laptop> Reply-To: Ram Pai References: <20110509142014.617e3100@jbarnes-desktop> <4DC9E415.5010402@kernel.org> <20110512180638.GA5012@ram-laptop> <20110512182229.GQ8195@ram-laptop> <20110512113726.123fd85b@jbarnes-desktop> <20110512123412.64e9b4cc@jbarnes-desktop> <4DCDD589.8010309@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4DCDD589.8010309@kernel.org> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 13, 2011 at 06:06:17PM -0700, Yinghai Lu wrote: > On 05/12/2011 12:34 PM, Jesse Barnes wrote: > > On Thu, 12 May 2011 12:18:43 -0700 > > Linus Torvalds wrote: > > > >> On Thu, May 12, 2011 at 11:37 AM, Jesse Barnes wrote: > >>> > >>> Linus, I don't have anything else queued up, so you may as well take > >>> this one directly if you want it in 2.6.39. It's a regression fix, but > >>> resource changes always make me nervous. Alternately, I could put it > >>> into 2.6.40 instead, the backport to 2.6.39.x if it survives until > >>> 2.6.40-rc2 or so... > >> > >> Considering the trouble resource allocation always ends up being, I'd > >> almost prefer that "mark it for stable and put it in the 2.6.40 > >> queue". > >> > >> Afaik this problem hasn't actually hit any "normal" users, has it? So ... > > > > Sounds good, thanks. Yeah I don't think it's hit anyone but Yinghai > > (at least I don't know of any other reports). > > > > please check this one, it should be safe for 2.6.39 ? > size0 = calculate_iosize(size, min_size, size1, > resource_size(b_res), 4096); > - size1 = !add_size? size0: > + size1 = (!add_head || (add_head && !add_size)) ? size0 : > calculate_iosize(size, min_size+add_size, size1, > resource_size(b_res), 4096); This solves the problem you encountered. But, I think, it still does not fix the following scenario: adjust_resource() failing to allocate additional resource to a hotplug bridge that has no children. In this case ->flags of that 'struct resource' continues to be set even when no resource is allocated to that hot-plug bridge. RP