From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zhou Wang Subject: Re: [PATCH] ACPI/PCI: Fix bus range comparation in pci_mcfg_lookup Date: Thu, 12 Jan 2017 08:21:00 +0800 Message-ID: <5876CBEC.9070406@hisilicon.com> References: <1483513206-113046-1-git-send-email-wangzhou1@hisilicon.com> <20170111213727.GO14532@bhelgaas-glaptop.roam.corp.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170111213727.GO14532@bhelgaas-glaptop.roam.corp.google.com> Sender: linux-pci-owner@vger.kernel.org To: Bjorn Helgaas Cc: "Rafael J. Wysocki" , Len Brown , Tomasz Nowicki , Jayachandran C , Lorenzo Pieralisi , jorn Helgaas , liudongdong3@huawei.com, gabriele.paoloni@huawei.com, xuwei5@hisilicon.com, linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-acpi@vger.kernel.org On 2017/1/12 5:37, Bjorn Helgaas wrote: > On Wed, Jan 04, 2017 at 03:00:06PM +0800, Zhou Wang wrote: >> The configuration data provided by an MCFG region (ie PCI segment and >> bus range) may span multiple host bridges. >> >> Current code in pci_mcfg_lookup() carries out an exact match of host >> bridge bus range start value against the MCFG region(s) bus range start >> value which would cause configurations like the following: >> >> MCFG region: >> bus range: 0x00~0xff. >> segment: 0. >> >> PCI host bridges configuration (segment numbers and bus ranges): >> host bridge 1: >> bus range: 0x00~0x1f. >> segment: 0. >> host bridge 2: >> bus range: 0x20~0x4f. >> segment: 0. >> >> to fail, in that the bus range start value for host bridge 2 does >> not match the bus range start value of the respective MCFG region. >> >> Relax the bus range check in pci_mcfg_lookup() to cater for >> PCI configurations with multiple host bridges sharing the same >> MCFG region. >> >> Signed-off-by: Zhou Wang >> Reviewed-by: Tomasz Nowicki >> Acked-by: Lorenzo Pieralisi > > Applied to pci/enumeration for v4.11 with the following changelog: > > PCI/ACPI: Fix bus range comparison in pci_mcfg_lookup() > > The configuration data provided by an MCFG entry, i.e., PCI segment and bus > range, may span multiple host bridges. > > pci_mcfg_lookup() previously required an exact match of the host bridge > starting bus and the MCFG starting bus, which made the following > configuration fail: > > MCFG region: > segment: 0 > bus range: 0x00-0xff > > host bridge > segment: 0 > bus range: 0x20-0x4f > > Relax the bus range check in pci_mcfg_lookup() so we can use any MCFG entry > that contains the required bus range, as we do in pci_mmconfig_lookup(). > > [bhelgaas: changelog] > Signed-off-by: Zhou Wang > Signed-off-by: Bjorn Helgaas > Reviewed-by: Tomasz Nowicki > Acked-by: Lorenzo Pieralisi > Hi Bjorn, Many thanks for modifying the commit message and merging this patch! Best regards, Zhou >> --- >> drivers/acpi/pci_mcfg.c | 5 ++--- >> 1 file changed, 2 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c >> index a6a4cea..2944353 100644 >> --- a/drivers/acpi/pci_mcfg.c >> +++ b/drivers/acpi/pci_mcfg.c >> @@ -195,11 +195,10 @@ int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres, >> goto skip_lookup; >> >> /* >> - * We expect exact match, unless MCFG entry end bus covers more than >> - * specified by caller. >> + * We expect the range in bus_res in the coverage of MCFG bus range. >> */ >> list_for_each_entry(e, &pci_mcfg_list, list) { >> - if (e->segment == seg && e->bus_start == bus_res->start && >> + if (e->segment == seg && e->bus_start <= bus_res->start && >> e->bus_end >= bus_res->end) { >> root->mcfg_addr = e->addr; >> } >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . > From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934726AbdALAVg (ORCPT ); Wed, 11 Jan 2017 19:21:36 -0500 Received: from szxga02-in.huawei.com ([119.145.14.65]:17866 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762534AbdALAVe (ORCPT ); Wed, 11 Jan 2017 19:21:34 -0500 Subject: Re: [PATCH] ACPI/PCI: Fix bus range comparation in pci_mcfg_lookup To: Bjorn Helgaas References: <1483513206-113046-1-git-send-email-wangzhou1@hisilicon.com> <20170111213727.GO14532@bhelgaas-glaptop.roam.corp.google.com> CC: "Rafael J. Wysocki" , Len Brown , Tomasz Nowicki , Jayachandran C , Lorenzo Pieralisi , jorn Helgaas , , , , , , From: Zhou Wang Message-ID: <5876CBEC.9070406@hisilicon.com> Date: Thu, 12 Jan 2017 08:21:00 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <20170111213727.GO14532@bhelgaas-glaptop.roam.corp.google.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.63.139.185] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A020204.5876CBF6.0269,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: d5b525d5b114a3bd48e672fd304b00a4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2017/1/12 5:37, Bjorn Helgaas wrote: > On Wed, Jan 04, 2017 at 03:00:06PM +0800, Zhou Wang wrote: >> The configuration data provided by an MCFG region (ie PCI segment and >> bus range) may span multiple host bridges. >> >> Current code in pci_mcfg_lookup() carries out an exact match of host >> bridge bus range start value against the MCFG region(s) bus range start >> value which would cause configurations like the following: >> >> MCFG region: >> bus range: 0x00~0xff. >> segment: 0. >> >> PCI host bridges configuration (segment numbers and bus ranges): >> host bridge 1: >> bus range: 0x00~0x1f. >> segment: 0. >> host bridge 2: >> bus range: 0x20~0x4f. >> segment: 0. >> >> to fail, in that the bus range start value for host bridge 2 does >> not match the bus range start value of the respective MCFG region. >> >> Relax the bus range check in pci_mcfg_lookup() to cater for >> PCI configurations with multiple host bridges sharing the same >> MCFG region. >> >> Signed-off-by: Zhou Wang >> Reviewed-by: Tomasz Nowicki >> Acked-by: Lorenzo Pieralisi > > Applied to pci/enumeration for v4.11 with the following changelog: > > PCI/ACPI: Fix bus range comparison in pci_mcfg_lookup() > > The configuration data provided by an MCFG entry, i.e., PCI segment and bus > range, may span multiple host bridges. > > pci_mcfg_lookup() previously required an exact match of the host bridge > starting bus and the MCFG starting bus, which made the following > configuration fail: > > MCFG region: > segment: 0 > bus range: 0x00-0xff > > host bridge > segment: 0 > bus range: 0x20-0x4f > > Relax the bus range check in pci_mcfg_lookup() so we can use any MCFG entry > that contains the required bus range, as we do in pci_mmconfig_lookup(). > > [bhelgaas: changelog] > Signed-off-by: Zhou Wang > Signed-off-by: Bjorn Helgaas > Reviewed-by: Tomasz Nowicki > Acked-by: Lorenzo Pieralisi > Hi Bjorn, Many thanks for modifying the commit message and merging this patch! Best regards, Zhou >> --- >> drivers/acpi/pci_mcfg.c | 5 ++--- >> 1 file changed, 2 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/acpi/pci_mcfg.c b/drivers/acpi/pci_mcfg.c >> index a6a4cea..2944353 100644 >> --- a/drivers/acpi/pci_mcfg.c >> +++ b/drivers/acpi/pci_mcfg.c >> @@ -195,11 +195,10 @@ int pci_mcfg_lookup(struct acpi_pci_root *root, struct resource *cfgres, >> goto skip_lookup; >> >> /* >> - * We expect exact match, unless MCFG entry end bus covers more than >> - * specified by caller. >> + * We expect the range in bus_res in the coverage of MCFG bus range. >> */ >> list_for_each_entry(e, &pci_mcfg_list, list) { >> - if (e->segment == seg && e->bus_start == bus_res->start && >> + if (e->segment == seg && e->bus_start <= bus_res->start && >> e->bus_end >= bus_res->end) { >> root->mcfg_addr = e->addr; >> } >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > . >