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=-16.7 required=3.0 tests=BAYES_00, 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 D80C5C4338F for ; Fri, 13 Aug 2021 18:14:41 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 7C8A2610CF for ; Fri, 13 Aug 2021 18:14:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 7C8A2610CF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 356C260710; Fri, 13 Aug 2021 18:14:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dqYYDOD7hNr8; Fri, 13 Aug 2021 18:14:37 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp3.osuosl.org (Postfix) with ESMTPS id 094F160690; Fri, 13 Aug 2021 18:14:36 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id E103BC001A; Fri, 13 Aug 2021 18:14:36 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 0A5E7C000E for ; Fri, 13 Aug 2021 18:14:36 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 077E280C06 for ; Fri, 13 Aug 2021 18:14:36 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 3X28RCWBHs16 for ; Fri, 13 Aug 2021 18:14:35 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by smtp1.osuosl.org (Postfix) with ESMTPS id 4CC7380B86 for ; Fri, 13 Aug 2021 18:14:35 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10075"; a="215599562" X-IronPort-AV: E=Sophos;i="5.84,319,1620716400"; d="scan'208";a="215599562" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Aug 2021 11:14:33 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.84,319,1620716400"; d="scan'208";a="508340240" Received: from otcwcpicx3.sc.intel.com ([172.25.55.73]) by fmsmga004.fm.intel.com with ESMTP; 13 Aug 2021 11:14:32 -0700 From: Fenghua Yu To: "Lu Baolu" , "Joerg Roedel" , "David Woodhouse" , "Ashok Raj" , "Dave Hansen" , "Jacob Jun Pan" , "Ravi V Shankar" Subject: [PATCH] iommu/vt-d: Fix PASID reference leak Date: Fri, 13 Aug 2021 18:13:45 +0000 Message-Id: <20210813181345.1870742-1-fenghua.yu@intel.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 Cc: Fenghua Yu , iommu@lists.linux-foundation.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" A PASID reference is increased whenever a device is bound to an mm (and its PASID) successfully (i.e. the device's sdev user count is increased). But the reference is not dropped every time the device is unbound successfully from the mm (i.e. the device's sdev user count is decreased). The reference is dropped only once by calling intel_svm_free_pasid() when there isn't any device bound to the mm. intel_svm_free_pasid() drops the reference and only frees the PASID on zero reference. Fix the issue by dropping the PASID reference and freeing the PASID when no reference on successful unbinding the device by calling intel_svm_free_pasid() . Signed-off-by: Fenghua Yu --- drivers/iommu/intel/svm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index 9b0f22bc0514..4b9b3f35ba0e 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -675,7 +675,6 @@ static int intel_svm_unbind_mm(struct device *dev, u32 pasid) kfree_rcu(sdev, rcu); if (list_empty(&svm->devs)) { - intel_svm_free_pasid(mm); if (svm->notifier.ops) { mmu_notifier_unregister(&svm->notifier, mm); /* Clear mm's pasid. */ @@ -690,6 +689,8 @@ static int intel_svm_unbind_mm(struct device *dev, u32 pasid) kfree(svm); } } + /* Drop a PASID reference and free it if no reference. */ + intel_svm_free_pasid(mm); } out: return ret; -- 2.32.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu