From patchwork Thu Sep 17 06:02:45 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 7202481 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 03B0E9F40A for ; Thu, 17 Sep 2015 06:00:34 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 34765208F9 for ; Thu, 17 Sep 2015 06:00:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3FE97208F4 for ; Thu, 17 Sep 2015 06:00:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753201AbbIQF7t (ORCPT ); Thu, 17 Sep 2015 01:59:49 -0400 Received: from mga02.intel.com ([134.134.136.20]:11986 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752989AbbIQF7s (ORCPT ); Thu, 17 Sep 2015 01:59:48 -0400 Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga101.jf.intel.com with ESMTP; 16 Sep 2015 22:59:48 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,544,1437462000"; d="scan'208";a="646519678" Received: from gerry-dev.bj.intel.com ([10.238.158.61]) by orsmga003.jf.intel.com with ESMTP; 16 Sep 2015 22:59:42 -0700 From: Jiang Liu To: "Rafael J . Wysocki" , Bjorn Helgaas , Thomas Gleixner , "Rafael J. Wysocki" , Len Brown Cc: Jiang Liu , wfg@linux.intel.com, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, x86@kernel.org Subject: [Bugfix 1/2] ACPI, PCI, irq: Do not share PCI IRQ with ISA IRQ Date: Thu, 17 Sep 2015 14:02:45 +0800 Message-Id: <1442469766-31264-1-git-send-email-jiang.liu@linux.intel.com> X-Mailer: git-send-email 1.7.10.4 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Avoid IRQs occupied by ISA IRQs when allocating IRQs for PCI link devices, otherwise it may cause interrupt storm due to incompatible pin attributes. This issue was triggered on a KVM virtual machine, which 1) uses IRQ9 for SCI in high level mode. 2) defines an PCI interrupt link device (LNKS) with IRQ9 as the only possible irq. 3) has an PCI device referring to link device LNKS. So it causes interrupt storm when enabling the PCI device because PCI IRQ works in low level mode. Signed-off-by: Jiang Liu Acked-by: Bjorn Helgaas --- drivers/acpi/pci_irq.c | 1 + drivers/acpi/pci_link.c | 13 +++++++++++++ include/linux/acpi.h | 1 + 3 files changed, 15 insertions(+) diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c index 6da0f9beab19..c9336751e5e3 100644 --- a/drivers/acpi/pci_irq.c +++ b/drivers/acpi/pci_irq.c @@ -372,6 +372,7 @@ static int acpi_isa_register_gsi(struct pci_dev *dev) /* Interrupt Line values above 0xF are forbidden */ if (dev->irq > 0 && (dev->irq <= 0xF) && + acpi_isa_irq_available(dev->irq) && (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) { dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n", pin_name(dev->pin), dev->irq); diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c index 3b4ea98e3ea0..246e50d22120 100644 --- a/drivers/acpi/pci_link.c +++ b/drivers/acpi/pci_link.c @@ -553,6 +553,13 @@ static int acpi_pci_link_allocate(struct acpi_pci_link *link) irq = link->irq.possible[i]; } } + if (acpi_irq_penalty[irq] >= PIRQ_PENALTY_ISA_ALWAYS) { + printk(KERN_ERR PREFIX "No IRQ available for %s [%s]. " + "Try pci=noacpi or acpi=off\n", + acpi_device_name(link->device), + acpi_device_bid(link->device)); + return -ENODEV; + } /* Attempt to enable the link device at this IRQ. */ if (acpi_pci_link_set(link, irq)) { @@ -821,6 +828,12 @@ void acpi_penalize_isa_irq(int irq, int active) } } +bool acpi_isa_irq_available(int irq) +{ + return irq >= 0 && (irq >= ARRAY_SIZE(acpi_irq_penalty) || + acpi_irq_penalty[irq] < PIRQ_PENALTY_ISA_ALWAYS); +} + /* * Penalize IRQ used by ACPI SCI. If ACPI SCI pin attributes conflict with * PCI IRQ attributes, mark ACPI SCI as ISA_ALWAYS so it won't be use for diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 7235c4851460..43856d19cf4d 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -217,6 +217,7 @@ struct pci_dev; int acpi_pci_irq_enable (struct pci_dev *dev); void acpi_penalize_isa_irq(int irq, int active); +bool acpi_isa_irq_available(int irq); void acpi_penalize_sci_irq(int irq, int trigger, int polarity); void acpi_pci_irq_disable (struct pci_dev *dev);