Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759937AbZFXQQ1 (ORCPT ); Wed, 24 Jun 2009 12:16:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751976AbZFXQQU (ORCPT ); Wed, 24 Jun 2009 12:16:20 -0400 Received: from hera.kernel.org ([140.211.167.34]:38438 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751238AbZFXQQT (ORCPT ); Wed, 24 Jun 2009 12:16:19 -0400 Subject: Re: Regression with commit f9cde5f in 2.6.30-gitX From: Jaswinder Singh Rajput To: Gary Hade Cc: Thomas Gleixner , Larry Finger , Jesse Barnes , LKML , Ingo Molnar , x86 maintainers , Len Brown , Linus Torvalds In-Reply-To: <20090624155632.GB7239@us.ibm.com> References: <4A418254.9050607@lwfinger.net> <1245845787.3093.3.camel@localhost.localdomain> <20090624155632.GB7239@us.ibm.com> Content-Type: text/plain Date: Wed, 24 Jun 2009 21:45:00 +0530 Message-Id: <1245860100.3216.7.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.24.5 (2.24.5-1.fc10) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2974 Lines: 71 On Wed, 2009-06-24 at 08:56 -0700, Gary Hade wrote: > On Wed, Jun 24, 2009 at 04:51:48PM +0200, Thomas Gleixner wrote: > > On Wed, 24 Jun 2009, Jaswinder Singh Rajput wrote: > > > Reported-by: Larry Finger > > > Signed-off-by: Jaswinder Singh Rajput > > > --- > > > arch/x86/pci/acpi.c | 16 ++++++++++------ > > > 1 files changed, 10 insertions(+), 6 deletions(-) > > > > > > diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c > > > index 16c3fda..0bc015f 100644 > > > --- a/arch/x86/pci/acpi.c > > > +++ b/arch/x86/pci/acpi.c > > > @@ -69,6 +69,9 @@ setup_resource(struct acpi_resource *acpi_res, void *data) > > > struct resource *root; > > > int max_root_bus_resources = PCI_BUS_NUM_RESOURCES; > > > > > > + if (info->res_num >= PCI_BUS_NUM_RESOURCES) > > > + return AE_OK; > > > + > > > status = resource_to_addr(acpi_res, &addr); > > > if (!ACPI_SUCCESS(status)) > > > return AE_OK; > > > @@ -94,17 +97,18 @@ setup_resource(struct acpi_resource *acpi_res, void *data) > > > if (bus_has_transparent_bridge(info->bus)) > > > max_root_bus_resources -= 3; > > > if (info->res_num >= max_root_bus_resources) { > > > - printk(KERN_WARNING "PCI: Failed to allocate 0x%lx-0x%lx " > > > - "from %s for %s due to _CRS returning more than " > > > - "%d resource descriptors\n", (unsigned long) res->start, > > > - (unsigned long) res->end, root->name, info->name, > > > - max_root_bus_resources); > > > + pr_warning("PCI: Failed to allocate 0x%lx-0x%lx " > > > + "from %s for %s due to _CRS returning more than " > > > + "%d resource descriptors\n", > > > + (unsigned long)res->start, (unsigned long)res->end, > > > + root->name, info->name, max_root_bus_resources); > > > > Can you please avoid mixing cleanup patches with bug fixes ? I almost > > did not see the line below. > > > > > + info->bus->resource[info->res_num] = res; > > > > Storing the resource in defeats the purpose of the original patch, > > which makes sure that we do _NOT_ use the last 3 slots of the resource > > array for a root bus with a transparent bridge. > > > > > info->res_num++; > > > > This is the real bug. info->res_num should not be incremented when we > > run out of resources already. > > This probably isn't needed but I don't think it is the cause of > the problem. It is just counting the number of _CRS returned > resources and I believe subsequent visits to setup_resource() > for additional returned resources will generate the same warning > as it also would if the instruction were removed and no longer > being used to keep an accurate count. > Yes, this count is needed to avoid PCI failure. Thanks, -- JSR -- 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/