Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751982Ab3CASUh (ORCPT ); Fri, 1 Mar 2013 13:20:37 -0500 Received: from mail-ie0-f182.google.com ([209.85.223.182]:42757 "EHLO mail-ie0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750779Ab3CASUf (ORCPT ); Fri, 1 Mar 2013 13:20:35 -0500 MIME-Version: 1.0 In-Reply-To: <1362158276-4901-1-git-send-email-nhorman@tuxdriver.com> References: <1362158276-4901-1-git-send-email-nhorman@tuxdriver.com> Date: Fri, 1 Mar 2013 10:20:35 -0800 X-Google-Sender-Auth: uwRt7aJ_eKs4FeLXoonDyWSGr6s Message-ID: Subject: Re: [PATCH] irq: add quirk for broken interrupt remapping on 55XX chipsets From: Yinghai Lu To: Neil Horman Cc: linux-kernel@vger.kernel.org, Prarit Bhargava , Don Zickus , Don Dutile , Bjorn Helgaas , Asit Mallick , linux-pci@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4296 Lines: 95 On Fri, Mar 1, 2013 at 9:17 AM, Neil Horman wrote: > A few years back intel published a spec update: > http://www.intel.com/content/dam/doc/specification-update/5520-and-5500-chipset-ioh-specification-update.pdf > > For the 5520 and 5500 chipsets which contained an errata (specificially errata > 53), which noted that these chipsets can't properly do interrupt remapping, and > as a result the recommend that interrupt remapping be disabled in bios. While > many vendors have a bios update to do exactly that, not all do, and of course > not all users update their bios to a level that corrects the problem. As a > result, occasionally interrupts can arrive at a cpu even after affinity for that > interrupt has be moved, leading to lost or spurrious interrupts (usually > characterized by the message: > kernel: do_IRQ: 7.71 No irq handler for vector (irq -1) > > There have been several incidents recently of people seeing this error, and > investigation has shown that they have system for which their BIOS level is such > that this feature was not properly turned off. As such, it would be good to > give them a reminder that their systems are vulnurable to this problem. > > Signed-off-by: Neil Horman > CC: Prarit Bhargava > CC: Don Zickus > CC: Don Dutile > CC: Bjorn Helgaas > CC: Asit Mallick > CC: linux-pci@vger.kernel.org > --- > drivers/iommu/intel_irq_remapping.c | 20 ++++++++++++++++++++ > include/linux/pci_ids.h | 2 ++ > 2 files changed, 22 insertions(+) > > diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c > index f3b8f23..9bfb6c2 100644 > --- a/drivers/iommu/intel_irq_remapping.c > +++ b/drivers/iommu/intel_irq_remapping.c > @@ -1113,3 +1113,23 @@ struct irq_remap_ops intel_irq_remap_ops = { > .msi_setup_irq = intel_msi_setup_irq, > .setup_hpet_msi = intel_setup_hpet_msi, > }; > + > + > +static void intel_remapping_check(struct pci_dev *dev) > +{ > + u8 revision; > + > + pci_read_config_byte(dev, PCI_REVISION_ID, &revision); > + > + if ((revision == 0x13) && irq_remapping_enabled) { > + pr_warn("WARNING WARNING WARNING WARNING WARNING WARNING\n" > + "This system BIOS has enabled interrupt remapping\n" > + "on a chipset that contains an errata making that\n" > + "feature unstable. Please reboot with nointremap\n" > + "added to the kernel command line and contact\n" > + "your BIOS vendor for an update"); > + } > +} > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5520_IOHUB, intel_remapping_check); > +DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5500_IOHUB, intel_remapping_check); only for x86 platform? If so, you can check that in arch/x86/kernel/early-quirks.c::early_quirks() and set one flag and later print warning and skip there if someone need to enable intr-remap. So users will not need to reboot the system... Thanks Yinghai > + > diff --git a/include/linux/pci_ids.h b/include/linux/pci_ids.h > index 31717bd..54027a6 100644 > --- a/include/linux/pci_ids.h > +++ b/include/linux/pci_ids.h > @@ -2732,6 +2732,8 @@ > #define PCI_DEVICE_ID_INTEL_LYNNFIELD_MC_CH2_RANK_REV2 0x2db2 > #define PCI_DEVICE_ID_INTEL_LYNNFIELD_MC_CH2_TC_REV2 0x2db3 > #define PCI_DEVICE_ID_INTEL_82855PM_HB 0x3340 > +#define PCI_DEVICE_ID_INTEL_5500_IOHUB 0x3403 > +#define PCI_DEVICE_ID_INTEL_5520_IOHUB 0x3406 > #define PCI_DEVICE_ID_INTEL_IOAT_TBG4 0x3429 > #define PCI_DEVICE_ID_INTEL_IOAT_TBG5 0x342a > #define PCI_DEVICE_ID_INTEL_IOAT_TBG6 0x342b > -- > 1.7.11.7 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-pci" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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/