From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <50418769.4030605@gmail.com> Date: Sat, 01 Sep 2012 11:56:25 +0800 From: Jiang Liu MIME-Version: 1.0 To: Yinghai Lu CC: Bjorn Helgaas , Jiang Liu , Taku Izumi , linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, kaneshige.kenji@jp.fujitsu.com Subject: Re: [PATCH 0/7][RESEND] acpi, pci: hostbridge hotplug support References: <20120810150955.e4ab3c7f.izumi.taku@jp.fujitsu.com> <50400D6E.1050108@huawei.com> <5040494E.8080501@huawei.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-acpi-owner@vger.kernel.org List-ID: On 09/01/2012 12:44 AM, Yinghai Lu wrote: > On Thu, Aug 30, 2012 at 10:42 PM, Bjorn Helgaas wrote: >> >> That's true. I think we should blindly probe for devices only when >> (1) the system does not have ACPI or (2) the DMI BIOS date is older >> than some date, e.g., 1 Jan 2013. For new systems with ACPI, we >> should only look at the host bridges described in ACPI. > > if those buses do not get scanned, then it should be enough. > > how about just removing pcibios_last_bus probing code? > > diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c > index 937bcec..3f3c460 100644 > --- a/arch/x86/pci/mmconfig-shared.c > +++ b/arch/x86/pci/mmconfig-shared.c > @@ -616,16 +616,6 @@ static void __init __pci_mmcfg_init(int early) > if (list_empty(&pci_mmcfg_list)) > return; > > - if (pcibios_last_bus < 0) { > - const struct pci_mmcfg_region *cfg; > - > - list_for_each_entry(cfg, &pci_mmcfg_list, list) { > - if (cfg->segment) > - break; > - pcibios_last_bus = cfg->end_bus; > - } > - } > - > if (pci_mmcfg_arch_init()) > pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF; > else { > > > also Nehalem *EX* and Westmere *EX* does not support EDAC. > > so if the user with Nehalem/Westmere Desktop version, want to use to > EDAC, they could just append > pci=last_bus=255 to get those buses scanned. I think this is a better solution than non-ACPI root bus hotplug. --Gerry