From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751925AbcFCAqQ (ORCPT ); Thu, 2 Jun 2016 20:46:16 -0400 Received: from mail-io0-f181.google.com ([209.85.223.181]:36128 "EHLO mail-io0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751227AbcFCAqP (ORCPT ); Thu, 2 Jun 2016 20:46:15 -0400 From: Roland Dreier To: Joerg Roedel Cc: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, David Woodhouse Subject: [PATCH] iommu/vt-d: Don't reject NTB devices due to scope mismatch Date: Thu, 2 Jun 2016 17:46:10 -0700 Message-Id: <1464914770-32107-1-git-send-email-roland@kernel.org> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Roland Dreier On a system with an Intel PCIe port configured as an NTB device, iommu initialization fails with DMAR: Device scope type does not match for 0000:80:03.0 This is because the DMAR table reports this device as having scope 2 (ACPI_DMAR_SCOPE_TYPE_BRIDGE): [0A0h 0160 1] Device Scope Entry Type : 02 [0A1h 0161 1] Entry Length : 08 [0A2h 0162 2] Reserved : 0000 [0A4h 0164 1] Enumeration ID : 00 [0A5h 0165 1] PCI Bus Number : 80 [0A6h 0166 2] PCI Path : 03,00 but the device has a type 0 PCI header: 80:03.0 Bridge [0680]: Intel Corporation Device [8086:2f0d] (rev 02) 00: 86 80 0d 2f 00 00 10 00 02 00 80 06 10 00 80 00 10: 0c 00 c0 00 c0 38 00 00 0c 00 00 00 80 38 00 00 20: 00 00 00 c8 00 00 10 c8 00 00 00 00 86 80 00 00 30: 00 00 00 00 60 00 00 00 00 00 00 00 ff 01 00 00 VT-d works perfectly on this system, so there's no reason to bail out on initialization due to this apparent scope mismatch. Use the class 0x0680 ("Other bridge device") as a heuristic for allowing DMAR initialization for non-bridge PCI devices listed with scope bridge. Signed-off-by: Roland Dreier --- drivers/iommu/dmar.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 6a86b5d1defa..2eff7b6c6c98 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -241,8 +241,20 @@ int dmar_insert_dev_scope(struct dmar_pci_notify_info *info, if (!dmar_match_pci_path(info, scope->bus, path, level)) continue; - if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT) ^ - (info->dev->hdr_type == PCI_HEADER_TYPE_NORMAL)) { + /* + * We expect devices with endpoint scope to have normal PCI + * headers, and devices with bridge scope to have bridge PCI + * headers. However PCI NTB devices may be listed in the + * DMAR table with bridge scope, even though they have a + * normal PCI header. NTB devices are identified by class + * "BRIDGE_OTHER" (0680h) - we don't declare a socpe mismatch + * for this special case. + */ + if ((scope->entry_type == ACPI_DMAR_SCOPE_TYPE_ENDPOINT && + info->dev->hdr_type != PCI_HEADER_TYPE_NORMAL) || + (scope->entry_type == ACPI_DMAR_SCOPE_TYPE_BRIDGE && + (info->dev->hdr_type == PCI_HEADER_TYPE_NORMAL && + info->dev->class >> 8 != PCI_CLASS_BRIDGE_OTHER))) { pr_warn("Device scope type does not match for %s\n", pci_name(info->dev)); return -EINVAL; -- 2.7.4