From 03bbcb2e7e292838bb0244f5a7816d194c911d62 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Tue, 16 Apr 2013 16:38:32 -0400 Subject: iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 [ Joerg: Removed CONFIG_IRQ_REMAP ifdef from early-quirks.c ] 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 Signed-off-by: Joerg Roedel --- drivers/iommu/intel_irq_remapping.c | 10 ++++++++++ drivers/iommu/irq_remapping.c | 6 ++++++ drivers/iommu/irq_remapping.h | 2 ++ 3 files changed, 18 insertions(+) (limited to 'drivers/iommu') diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index f3b8f23b5d8..5b19b2d6ec2 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 d56f8c17c5f..3c11043bdee 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 ecb63767040..90c4dae5a46 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 */ -- cgit v1.2.3