Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932121Ab2HGVkD (ORCPT ); Tue, 7 Aug 2012 17:40:03 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:58219 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932070Ab2HGVjn (ORCPT ); Tue, 7 Aug 2012 17:39:43 -0400 From: Seth Forshee To: linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, x86@kernel.org Cc: Joerg Roedel , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Len Brown , Joerg Roedel , Suresh Siddha , Yinghai Lu Subject: [PATCH v2] irq_remap: disable IRQ remapping if any IOAPIC lacks an IOMMU Date: Tue, 7 Aug 2012 16:39:33 -0500 Message-Id: <1344375573-16716-1-git-send-email-seth.forshee@canonical.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <20120807210408.GK1917@8bytes.org> References: <20120807210408.GK1917@8bytes.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1805 Lines: 54 The ACPI tables in the Macbook Air 5,1 define a single IOAPIC with id 2, but the only remapping unit described in the DMAR table matches id 0. Interrupt remapping fails as a result, and the kernel panics with the message "timer doesn't work through Interrupt-remapped IO-APIC." To fix this, check each IOAPIC for a corresponding IOMMU. If an IOMMU is not found, do not allow IRQ remapping to be enabled. v2: Move check to parse_ioapics_under_ir(), raise log level to KERN_ERR, and add FW_BUG to the log message Acked-by: Suresh Siddha Signed-off-by: Seth Forshee --- drivers/iommu/intel_irq_remapping.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c index e0b18f3..84e5dc3 100644 --- a/drivers/iommu/intel_irq_remapping.c +++ b/drivers/iommu/intel_irq_remapping.c @@ -736,6 +736,7 @@ int __init parse_ioapics_under_ir(void) { struct dmar_drhd_unit *drhd; int ir_supported = 0; + int ioapic_idx; for_each_drhd_unit(drhd) { struct intel_iommu *iommu = drhd->iommu; @@ -754,6 +755,16 @@ int __init parse_ioapics_under_ir(void) return -1; } + for (ioapic_idx = 0; ioapic_idx < nr_ioapics; ioapic_idx++) { + int ioapic_id = mpc_ioapic_id(ioapic_idx); + if (!map_ioapic_to_ir(ioapic_id)) { + pr_err(FW_BUG "ioapic %d has no mapping iommu, " + "interrupt remapping will be disabled\n", + ioapic_id); + return -1; + } + } + return ir_supported; } -- 1.7.9.5 -- 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/