From patchwork Tue Feb 2 00:04:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Filippo Sironi X-Patchwork-Id: 374564 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EDA8C433E6 for ; Tue, 2 Feb 2021 00:06:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D651F64EDC for ; Tue, 2 Feb 2021 00:06:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231282AbhBBAF6 (ORCPT ); Mon, 1 Feb 2021 19:05:58 -0500 Received: from smtp-fw-4101.amazon.com ([72.21.198.25]:6575 "EHLO smtp-fw-4101.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229593AbhBBAF4 (ORCPT ); Mon, 1 Feb 2021 19:05:56 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.de; i=@amazon.de; q=dns/txt; s=amazon201209; t=1612224355; x=1643760355; h=from:to:cc:subject:date:message-id:mime-version; bh=SKhpC//DwujKdlsmKEU28oL8CPZ5Xde+3TXTsyPTINI=; b=fEcyCal6xdVKx8jsHWtLyrcsqIVQNjup4kG6+Y/0RzDVOEWHc4DK5Yib v4sZDOfN62uoq45joqCvr4sUYiLEYSvKyWspA4CQN7nxGIT4Np6QUibic Hs9VXQxh1wjeYpmPXh9/HovNJL2NfZmvmS/psqdz4IoBHm0U0hfINAaxH 8=; X-IronPort-AV: E=Sophos;i="5.79,393,1602547200"; d="scan'208";a="79159621" Received: from iad12-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-2b-859fe132.us-west-2.amazon.com) ([10.43.8.2]) by smtp-border-fw-out-4101.iad4.amazon.com with ESMTP; 02 Feb 2021 00:05:07 +0000 Received: from EX13D02EUC001.ant.amazon.com (pdx1-ws-svc-p6-lb9-vlan2.pdx.amazon.com [10.236.137.194]) by email-inbound-relay-2b-859fe132.us-west-2.amazon.com (Postfix) with ESMTPS id B1E9A221CD0; Tue, 2 Feb 2021 00:05:06 +0000 (UTC) Received: from u2196cf9297dc59.ant.amazon.com (10.43.162.32) by EX13D02EUC001.ant.amazon.com (10.43.164.92) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 2 Feb 2021 00:05:02 +0000 From: Filippo Sironi To: CC: , , , , Joerg Roedel Subject: [PATCH 1/2 for Linux 4.14] iommu/vt-d: Gracefully handle DMAR units with no supported address widths Date: Tue, 2 Feb 2021 01:04:44 +0100 Message-ID: <20210202000445.711-1-sironi@amazon.de> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 X-Originating-IP: [10.43.162.32] X-ClientProxiedBy: EX13D11UWB002.ant.amazon.com (10.43.161.20) To EX13D02EUC001.ant.amazon.com (10.43.164.92) Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: David Woodhouse commit c40aaaac1018ff1382f2d35df5129a6bcea3df6b upstream. Instead of bailing out completely, such a unit can still be used for interrupt remapping. Signed-off-by: David Woodhouse Reviewed-by: Lu Baolu Link: https://lore.kernel.org/linux-iommu/549928db2de6532117f36c9c810373c14cf76f51.camel@infradead.org/ Signed-off-by: Joerg Roedel [ context change due to moving drivers/iommu/dmar.c to drivers/iommu/intel/dmar.c ] Signed-off-by: Filippo Sironi --- drivers/iommu/dmar.c | 44 ++++++++++++++++++++++++++++++-------------- 1 file changed, 30 insertions(+), 14 deletions(-) diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 1f527ca60955..4d62dd2131e2 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -1026,8 +1026,8 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) { struct intel_iommu *iommu; u32 ver, sts; - int agaw = 0; - int msagaw = 0; + int agaw = -1; + int msagaw = -1; int err; if (!drhd->reg_base_addr) { @@ -1052,17 +1052,28 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) } err = -EINVAL; - agaw = iommu_calculate_agaw(iommu); - if (agaw < 0) { - pr_err("Cannot get a valid agaw for iommu (seq_id = %d)\n", - iommu->seq_id); - goto err_unmap; + if (cap_sagaw(iommu->cap) == 0) { + pr_info("%s: No supported address widths. Not attempting DMA translation.\n", + iommu->name); + drhd->ignored = 1; } - msagaw = iommu_calculate_max_sagaw(iommu); - if (msagaw < 0) { - pr_err("Cannot get a valid max agaw for iommu (seq_id = %d)\n", - iommu->seq_id); - goto err_unmap; + + if (!drhd->ignored) { + agaw = iommu_calculate_agaw(iommu); + if (agaw < 0) { + pr_err("Cannot get a valid agaw for iommu (seq_id = %d)\n", + iommu->seq_id); + drhd->ignored = 1; + } + } + if (!drhd->ignored) { + msagaw = iommu_calculate_max_sagaw(iommu); + if (msagaw < 0) { + pr_err("Cannot get a valid max agaw for iommu (seq_id = %d)\n", + iommu->seq_id); + drhd->ignored = 1; + agaw = -1; + } } iommu->agaw = agaw; iommu->msagaw = msagaw; @@ -1089,7 +1100,12 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) raw_spin_lock_init(&iommu->register_lock); - if (intel_iommu_enabled) { + /* + * This is only for hotplug; at boot time intel_iommu_enabled won't + * be set yet. When intel_iommu_init() runs, it registers the units + * present at boot time, then sets intel_iommu_enabled. + */ + if (intel_iommu_enabled && !drhd->ignored) { err = iommu_device_sysfs_add(&iommu->iommu, NULL, intel_iommu_groups, "%s", iommu->name); @@ -1118,7 +1134,7 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) static void free_iommu(struct intel_iommu *iommu) { - if (intel_iommu_enabled) { + if (intel_iommu_enabled && iommu->iommu.ops) { iommu_device_unregister(&iommu->iommu); iommu_device_sysfs_remove(&iommu->iommu); }