From nobody Mon Feb 9 14:31:23 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E151C6FD1C for ; Fri, 24 Mar 2023 12:03:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231808AbjCXMDK (ORCPT ); Fri, 24 Mar 2023 08:03:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231833AbjCXMCv (ORCPT ); Fri, 24 Mar 2023 08:02:51 -0400 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A205265B8; Fri, 24 Mar 2023 05:02:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679659361; x=1711195361; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=M/Jk/NyOL6YOkh9WpMFp/FMLnkzRYwNbBzLyoNFzzAU=; b=Tp5a5DlI92vpGpnCNmXRTLEMyGYXWHELMjRzcubt+IXqopxokZmzqfSW KVSN/K4KyaboIXyMOiehaL3XB5f6R1ZWMjduEBj56Sv/oZXVUYU2goAvK 5VbV+QrGuVMk4L6DHat3uMMRt2WcZF2ZUdb0TLcB4k+AxCRd8QucJSKys 89HQLLUybgG+nAwV4980m3FlgoSsJcBkHx0+kbrPL2hWtRBdAYUFeKtkf kQzvBdqY6XWAu2splMDWXmziMo4J5r/lzKq+O0+b3GvVF5j4tqjQkSkLO 9dgZMZzQ+W1F1XjNd3hPwzDnhrb28DP2wakcng75YVM0MXbDF7p1Fwe8o g==; X-IronPort-AV: E=McAfee;i="6600,9927,10658"; a="323634194" X-IronPort-AV: E=Sophos;i="5.98,287,1673942400"; d="scan'208";a="323634194" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2023 05:02:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10658"; a="682674914" X-IronPort-AV: E=Sophos;i="5.98,287,1673942400"; d="scan'208";a="682674914" Received: from allen-box.sh.intel.com ([10.239.159.48]) by orsmga002.jf.intel.com with ESMTP; 24 Mar 2023 05:02:38 -0700 From: Lu Baolu To: iommu@lists.linux.dev, dmaengine@vger.kernel.org Cc: Joerg Roedel , Will Deacon , Robin Murphy , Kevin Tian , Fenghua Yu , Dave Jiang , Vinod Koul , Jacob Pan , linux-kernel@vger.kernel.org, Lu Baolu Subject: [PATCH v3 6/6] iommu/vt-d: Remove unnecessary checks in iopf disabling path Date: Fri, 24 Mar 2023 20:02:34 +0800 Message-Id: <20230324120234.313643-7-baolu.lu@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230324120234.313643-1-baolu.lu@linux.intel.com> References: <20230324120234.313643-1-baolu.lu@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" iommu_unregister_device_fault_handler() and iopf_queue_remove_device() are called after device has stopped issuing new page falut requests and all outstanding page requests have been drained. They should never fail. Trigger a warning if it happens unfortunately. Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian --- drivers/iommu/intel/iommu.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index cd3a3c4b5e64..c771233d6f2a 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4707,7 +4707,6 @@ static int intel_iommu_disable_iopf(struct device *de= v) { struct device_domain_info *info =3D dev_iommu_priv_get(dev); struct intel_iommu *iommu =3D info->iommu; - int ret; =20 if (!info->pri_enabled) return -EINVAL; @@ -4723,15 +4722,15 @@ static int intel_iommu_disable_iopf(struct device *= dev) pci_disable_pri(to_pci_dev(dev)); info->pri_enabled =3D 0; =20 - ret =3D iommu_unregister_device_fault_handler(dev); - if (ret) - return ret; - - ret =3D iopf_queue_remove_device(iommu->iopf_queue, dev); - if (ret) - iommu_register_device_fault_handler(dev, iommu_queue_iopf, dev); + /* + * With PRI disabled and outstanding PRQs drained, unregistering + * fault handler and removing device from iopf queue should never + * fail. + */ + WARN_ON(iommu_unregister_device_fault_handler(dev)); + WARN_ON(iopf_queue_remove_device(iommu->iopf_queue, dev)); =20 - return ret; + return 0; } =20 static int --=20 2.34.1