Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965434Ab3DPWIc (ORCPT ); Tue, 16 Apr 2013 18:08:32 -0400 Received: from mx1.redhat.com ([209.132.183.28]:60224 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965255Ab3DPWIb (ORCPT ); Tue, 16 Apr 2013 18:08:31 -0400 Message-ID: <516DCBC8.9070409@redhat.com> Date: Tue, 16 Apr 2013 18:08:08 -0400 From: Don Dutile User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130108 Thunderbird/10.0.12 MIME-Version: 1.0 To: Neil Horman CC: linux-kernel@vger.kernel.org, Prarit Bhargava , Don Zickus , Bjorn Helgaas , Asit Mallick , David Woodhouse , linux-pci@vger.kernel.org, Joerg Roedel , Konrad Rzeszutek Wilk , =?UTF-8?B?QXJrYWRpdXN6IE0=?= =?UTF-8?B?acWba2lld2ljeg==?= Subject: Re: [PATCH v10] irq: add quirk for broken interrupt remapping on 55XX chipsets References: <1362158276-4901-1-git-send-email-nhorman@tuxdriver.com> <1366144712-23460-1-git-send-email-nhorman@tuxdriver.com> In-Reply-To: <1366144712-23460-1-git-send-email-nhorman@tuxdriver.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8435 Lines: 240 On 04/16/2013 04:38 PM, 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. For > details of those that reported the problem, please see: > https://bugzilla.redhat.com/show_bug.cgi?id=887006 > > Signed-off-by: Neil Horman > CC: Prarit Bhargava > CC: Don Zickus > CC: Don Dutile > CC: Bjorn Helgaas > CC: Asit Mallick > CC: David Woodhouse > CC: linux-pci@vger.kernel.org > CC: Joerg Roedel > CC: Konrad Rzeszutek Wilk > CC: Arkadiusz Miśkiewicz > --- > > Change notes: > > v2) > > * Moved the quirk to the x86 arch, since consensus seems to be that the 55XX > chipset series is x86 only. I decided however to keep the quirk as a regular > quirk, not an early_quirk. Early quirks have no way currently to determine if > BIOS has properly disabled the feature in the iommu, at least not without > significant hacking, and since its quite possible this will be a short lived > quirk, should Don Z's workaround code prove successful (and it looks like it may > well), I don't think that necessecary. > > * Removed the WARNING banner from the quirk, and added the HW_ERR token to the > string, I opted to leave the newlines in place however, as I really couldnt > find a way to keep the text on a single line is still legible from a code > perspective. I think theres enough language in there that using cscope on just > about any substring however will turn it up, and again, this may be a short > lived quirk. > > v3) > > * Removed defines from pci_ids.h, and used direct id values as per request from > Bjorn. > > v4) > > * Converted pr_warn to WARN_TAINT(TAINT_FIRMWARE_WORKAROUND) as per David > Woodhouse > > v5) > > * Moved check to an early quirk, and flagged the broken chip, so we could > reasonably disable irq remapping during bootup. > > v6) > > * Clean up of stupid extra thrash in quirks.c > > v7) > > * Move broken check to intel_irq_remapping.c > * Fixed another typo > * Finally made the reference bugzilla public > > v8) > > * Removed extraneous code from irq_remapping_enabled > > v9) > > * Fix stupid build break from rushing to shuffle simmilar header files about > Thanks to Arkadiusz Miśkiewicz for pointing it out > > v10) > > * Rewrite to hide the irq_remap_broken variable so we don't need to pull in a > private header file /me waiting for v11... /me runs! ;-) Neil, Looks good, and kudos on your tenacity through all the revs. - Don(Dutile) > --- > arch/x86/include/asm/irq_remapping.h | 1 + > arch/x86/kernel/early-quirks.c | 26 ++++++++++++++++++++++++++ > drivers/iommu/intel_irq_remapping.c | 10 ++++++++++ > drivers/iommu/irq_remapping.c | 6 ++++++ > drivers/iommu/irq_remapping.h | 2 ++ > 5 files changed, 45 insertions(+) > > diff --git a/arch/x86/include/asm/irq_remapping.h b/arch/x86/include/asm/irq_remapping.h > index 95fd352..d740cb4 100644 > --- a/arch/x86/include/asm/irq_remapping.h > +++ b/arch/x86/include/asm/irq_remapping.h > @@ -28,6 +28,7 @@ > > extern void setup_irq_remapping_ops(void); > extern int irq_remapping_supported(void); > +extern void set_irq_remapping_broken(void); > extern int irq_remapping_prepare(void); > extern int irq_remapping_enable(void); > extern void irq_remapping_disable(void); > diff --git a/arch/x86/kernel/early-quirks.c b/arch/x86/kernel/early-quirks.c > index 3755ef4..589092d 100644 > --- a/arch/x86/kernel/early-quirks.c > +++ b/arch/x86/kernel/early-quirks.c > @@ -18,6 +18,7 @@ > #include > #include > #include > +#include > > static void __init fix_hypertransport_config(int num, int slot, int func) > { > @@ -192,6 +193,27 @@ static void __init ati_bugs_contd(int num, int slot, int func) > } > #endif > > +#ifdef CONFIG_IRQ_REMAP > +static void __init intel_remapping_check(int num, int slot, int func) > +{ > + u8 revision; > + > + revision = read_pci_config_byte(num, slot, func, PCI_REVISION_ID); > + > + /* > + * Revision 0x13 of this chipset supports irq remapping > + * but has an erratum that breaks its behavior, flag it as such > + */ > + if (revision == 0x13) > + set_irq_remapping_broken(); > + > +} > +#else > +static void __init intel_remapping_check(int num, int slot, int func) > +{ > +} > +#endif > + > #define QFLAG_APPLY_ONCE 0x1 > #define QFLAG_APPLIED 0x2 > #define QFLAG_DONE (QFLAG_APPLY_ONCE|QFLAG_APPLIED) > @@ -221,6 +243,10 @@ static struct chipset early_qrk[] __initdata = { > PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs }, > { PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, > PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs_contd }, > + { PCI_VENDOR_ID_INTEL, 0x3403, PCI_CLASS_BRIDGE_HOST, > + PCI_BASE_CLASS_BRIDGE, 0, intel_remapping_check }, > + { PCI_VENDOR_ID_INTEL, 0x3406, PCI_CLASS_BRIDGE_HOST, > + PCI_BASE_CLASS_BRIDGE, 0, intel_remapping_check }, > {} > }; > > diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c > index f3b8f23..5b19b2d 100644 > --- a/drivers/iommu/intel_irq_remapping.c > +++ b/drivers/iommu/intel_irq_remapping.c > @@ -524,6 +524,16 @@ static int __init intel_irq_remapping_supported(void) > > if (disable_irq_remap) > return 0; > + if (irq_remap_broken) { > + WARN_TAINT(1, TAINT_FIRMWARE_WORKAROUND, > + "This system BIOS has enabled interrupt remapping\n" > + "on a chipset that contains an erratum making that\n" > + "feature unstable. To maintain system stability\n" > + "interrupt remapping is being disabled. Please\n" > + "contact your BIOS vendor for an update\n"); > + disable_irq_remap = 1; > + return 0; > + } > > if (!dmar_ir_support()) > return 0; > diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c > index d56f8c1..3c11043 100644 > --- a/drivers/iommu/irq_remapping.c > +++ b/drivers/iommu/irq_remapping.c > @@ -19,6 +19,7 @@ > int irq_remapping_enabled; > > int disable_irq_remap; > +int irq_remap_broken; > int disable_sourceid_checking; > int no_x2apic_optout; > > @@ -211,6 +212,11 @@ void __init setup_irq_remapping_ops(void) > #endif > } > > +void set_irq_remapping_broken(void) > +{ > + irq_remap_broken = 1; > +} > + > int irq_remapping_supported(void) > { > if (disable_irq_remap) > diff --git a/drivers/iommu/irq_remapping.h b/drivers/iommu/irq_remapping.h > index ecb6376..90c4dae 100644 > --- a/drivers/iommu/irq_remapping.h > +++ b/drivers/iommu/irq_remapping.h > @@ -32,6 +32,7 @@ struct pci_dev; > struct msi_msg; > > extern int disable_irq_remap; > +extern int irq_remap_broken; > extern int disable_sourceid_checking; > extern int no_x2apic_optout; > extern int irq_remapping_enabled; > @@ -89,6 +90,7 @@ extern struct irq_remap_ops amd_iommu_irq_ops; > > #define irq_remapping_enabled 0 > #define disable_irq_remap 1 > +#define irq_remap_broken 0 > > #endif /* CONFIG_IRQ_REMAP */ > -- 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/