From patchwork Tue Feb 2 13:39:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 376064 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=-18.7 required=3.0 tests=BAYES_00,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 73BE9C433DB for ; Tue, 2 Feb 2021 15:07:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4B13564FB0 for ; Tue, 2 Feb 2021 15:07:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234626AbhBBPHi (ORCPT ); Tue, 2 Feb 2021 10:07:38 -0500 Received: from mail.kernel.org ([198.145.29.99]:51458 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233984AbhBBOQ2 (ORCPT ); Tue, 2 Feb 2021 09:16:28 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id CFC0D64FBF; Tue, 2 Feb 2021 13:54:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1612274045; bh=dwKH/4TDRzTRZs7MRU1yY+nTS5jNZIVwmaNcs2vNzAQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KY9P+RYgSM255Fu+kaw9bQ6n8W+xziCF5t47Dj0WM+m1eHfeFoMknc08SBvS5jUSy WJ6GgVkDCeDWpGrmkaJpBUlxrTuYPp7B9eyYCx4JfeegQhIhHYkSyg90s/teKK6Q3K tOYqlx4qKHyTnfzQvS9pPRkBlczrKvZKWr3QR8Z8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, David Woodhouse , Lu Baolu , Joerg Roedel , Filippo Sironi Subject: [PATCH 4.19 31/37] iommu/vt-d: Gracefully handle DMAR units with no supported address widths Date: Tue, 2 Feb 2021 14:39:14 +0100 Message-Id: <20210202132944.227111350@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210202132942.915040339@linuxfoundation.org> References: <20210202132942.915040339@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 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 Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/dmar.c | 46 +++++++++++++++++++++++++++++++--------------- 1 file changed, 31 insertions(+), 15 deletions(-) --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -1029,8 +1029,8 @@ static int alloc_iommu(struct dmar_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) { @@ -1055,17 +1055,28 @@ static int alloc_iommu(struct dmar_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; - } - 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 (cap_sagaw(iommu->cap) == 0) { + pr_info("%s: No supported address widths. Not attempting DMA translation.\n", + iommu->name); + drhd->ignored = 1; + } + + 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; @@ -1092,7 +1103,12 @@ static int alloc_iommu(struct dmar_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); @@ -1121,7 +1137,7 @@ error: 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); }