From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 83741C432C2 for ; Wed, 25 Sep 2019 13:23:37 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5FB4B21D7C for ; Wed, 25 Sep 2019 13:23:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5FB4B21D7C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 8A135DAF; Wed, 25 Sep 2019 13:23:23 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id BBFBBDA4 for ; Wed, 25 Sep 2019 13:23:22 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 490988A for ; Wed, 25 Sep 2019 13:23:14 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 224C5528; Wed, 25 Sep 2019 15:23:02 +0200 (CEST) From: Joerg Roedel To: iommu@lists.linux-foundation.org, Joerg Roedel Subject: [PATCH 5/6] iommu/amd: Lock dev_data in attach/detach code paths Date: Wed, 25 Sep 2019 15:22:59 +0200 Message-Id: <20190925132300.3038-6-joro@8bytes.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190925132300.3038-1-joro@8bytes.org> References: <20190925132300.3038-1-joro@8bytes.org> Cc: Filippo Sironi , jroedel@suse.de X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Archived-At: List-Archive: From: Joerg Roedel Make sure that attaching a detaching a device can't race against each other and protect the iommu_dev_data with a spin_lock in these code paths. Fixes: 92d420ec028d ("iommu/amd: Relax locking in dma_ops path") Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 9 +++++++++ drivers/iommu/amd_iommu_types.h | 3 +++ 2 files changed, 12 insertions(+) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 459247c32dc0..bac4e20a5919 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -201,6 +201,7 @@ static struct iommu_dev_data *alloc_dev_data(u16 devid) if (!dev_data) return NULL; + spin_lock_init(&dev_data->lock); dev_data->devid = devid; ratelimit_default_init(&dev_data->rs); @@ -2157,6 +2158,8 @@ static int attach_device(struct device *dev, dev_data = get_dev_data(dev); + spin_lock(&dev_data->lock); + ret = -EBUSY; if (dev_data->domain != NULL) goto out; @@ -2199,6 +2202,8 @@ static int attach_device(struct device *dev, domain_flush_complete(domain); out: + spin_unlock(&dev_data->lock); + spin_unlock_irqrestore(&domain->lock, flags); return ret; @@ -2218,6 +2223,8 @@ static void detach_device(struct device *dev) spin_lock_irqsave(&domain->lock, flags); + spin_lock(&dev_data->lock); + /* * First check if the device is still attached. It might already * be detached from its domain because the generic @@ -2240,6 +2247,8 @@ static void detach_device(struct device *dev) dev_data->ats.enabled = false; out: + spin_unlock(&dev_data->lock); + spin_unlock_irqrestore(&domain->lock, flags); } diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h index 0186501ab971..c9c1612d52e0 100644 --- a/drivers/iommu/amd_iommu_types.h +++ b/drivers/iommu/amd_iommu_types.h @@ -633,6 +633,9 @@ struct devid_map { * This struct contains device specific data for the IOMMU */ struct iommu_dev_data { + /*Protect against attach/detach races */ + spinlock_t lock; + struct list_head list; /* For domain->dev_list */ struct llist_node dev_data_list; /* For global dev_data_list */ struct protection_domain *domain; /* Domain the device is bound to */ -- 2.17.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu