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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 06CADC74A5B for ; Wed, 29 Mar 2023 22:42:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230399AbjC2Wma (ORCPT ); Wed, 29 Mar 2023 18:42:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229560AbjC2Wm3 (ORCPT ); Wed, 29 Mar 2023 18:42:29 -0400 Received: from NAM04-BN8-obe.outbound.protection.outlook.com (mail-bn8nam04on2120.outbound.protection.outlook.com [40.107.100.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E8B7E5; Wed, 29 Mar 2023 15:42:25 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=k2jjQitQC1FY3ijl9S9lOyxhJuAAxpEd9hogaj2rQ/zFUIutk7FSo9KhV6F7UWbI72U3q/bDCVWNLTZBlg00kG22opBPUhim37ih+ORg+7H5YRxviYCAp5Wj6TLwuTqGTSsxXCPI/O62L4EzVaL68bdNJ9dB5Y8Apil7kkF3aLPG5QnuMOTF+krc9XXMs0fQCFZCTintp/tZ7Rc/TIVOBZyJq/JgClpVXs9g1AHp1pA+tG5O5q85pQtoin1+jJg0F7lZeBEuwOx3hLGDe2Hkgsk0gMSOv2oWHClkmMY7p2PgK+KGkVpCLm192XzXEYtZrES5/0gb3BDyU+b2oUISOg== ARC-Message-Signature: i=1; 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b=cMrd0ksZC9+1RAGe+297aLNSDxmzNHv0Ug4lVSZS3GGRjv0PgNZ9DVc24Nc2ro0VDSzSVviOhBmqgYU0tFfDDsP0eatedG7LzwmROWn9qLmwjFEgWYWGDNrarJqhnUGSCqwm/i8uTyZvJ/fjHLxv0Iwu6It4VhX8tdxqpt89fYc= Received: from SA1PR21MB1335.namprd21.prod.outlook.com (2603:10b6:806:1f2::11) by IA1PR21MB3400.namprd21.prod.outlook.com (2603:10b6:208:3e3::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.6277.6; Wed, 29 Mar 2023 22:42:22 +0000 Received: from SA1PR21MB1335.namprd21.prod.outlook.com ([fe80::2e52:d6aa:9a99:500a]) by SA1PR21MB1335.namprd21.prod.outlook.com ([fe80::2e52:d6aa:9a99:500a%5]) with mapi id 15.20.6277.010; Wed, 29 Mar 2023 22:42:22 +0000 From: Dexuan Cui To: "Michael Kelley (LINUX)" , "bhelgaas@google.com" , "davem@davemloft.net" , "edumazet@google.com" , Haiyang Zhang , Jake Oshins , "kuba@kernel.org" , "kw@linux.com" , KY Srinivasan , "leon@kernel.org" , "linux-pci@vger.kernel.org" , "lpieralisi@kernel.org" , "pabeni@redhat.com" , "robh@kernel.org" , "saeedm@nvidia.com" , "wei.liu@kernel.org" , Long Li , "boqun.feng@gmail.com" CC: "linux-hyperv@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-rdma@vger.kernel.org" , "netdev@vger.kernel.org" Subject: RE: [PATCH 6/6] PCI: hv: Use async probing to reduce boot time Thread-Topic: [PATCH 6/6] PCI: hv: Use async probing to reduce boot time Thread-Index: AQHZYTE3Y7FHmXDCGE2Fxs3dSXPnlK8R+TMggABgSeA= Date: Wed, 29 Mar 2023 22:42:22 +0000 Message-ID: References: <20230328045122.25850-1-decui@microsoft.com> <20230328045122.25850-7-decui@microsoft.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: msip_labels: MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_ActionId=c1c38967-f9ee-4864-a2bc-af561a32b5d8;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_ContentBits=0;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_Enabled=true;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_Method=Standard;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_Name=Internal;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_SetDate=2023-03-29T16:44:56Z;MSIP_Label_f42aa342-8706-4288-bd11-ebb85995028c_SiteId=72f988bf-86f1-41af-91ab-2d7cd011db47; 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charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SA1PR21MB1335.namprd21.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: f668c469-a152-43d7-e46e-08db30a6dcab X-MS-Exchange-CrossTenant-originalarrivaltime: 29 Mar 2023 22:42:22.7777 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: uKbTw7xmrN1a3tMOqPWMGE0Bu7y2BtFVLp43CoyINuVOq/G/i/C7kbu8K+v6T4jV1+vCXoYBixDBeU0+cRe9HA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR21MB3400 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org > From: Michael Kelley (LINUX) > Sent: Wednesday, March 29, 2023 9:55 AM >=20 > From: Dexuan Cui > > > > Commit 414428c5da1c ("PCI: hv: Lock PCI bus on device eject") added the > > pci_lock_rescan_remove() and pci_unlock_rescan_remove() to address the > > race between create_root_hv_pci_bus() and hv_eject_device_work(), but i= t > > doesn't really work well. > > > > Now with hbus->state_lock and other fixes, the race is resolved, so > > remove pci_{lock,unlock}_rescan_remove(). >=20 > Commit 414428c5da1c added the calls to pci_lock/unlock_rescan_remove() > in both create_root_hv_pci_bus() and in hv_eject_device_work(). This > patch removes the calls only in create_reboot_hv_pci_bus(), but leaves > them in hv_eject_device_work(), in hv_pci_remove(), and in=20 > pci_devices_present_work(). > So evidently it is still needed to provide exclusion for other cases. Pe= rhaps > your commit message could clarify that only the exclusion of > create_root_hv_pci_bus() > is now superfluous because of the > hbus->state_lock. And commit 414428c5da1c > isn't fully reverted > because evidently the lock is still needed in hv_eject_device_work(). >=20 > Michael Thanks! I'll update the commit message in v2.