From patchwork Tue Jan 8 16:52:21 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiang Liu X-Patchwork-Id: 210441 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id EE9292C0093 for ; Wed, 9 Jan 2013 03:53:55 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756778Ab3AHQwp (ORCPT ); Tue, 8 Jan 2013 11:52:45 -0500 Received: from mail-da0-f44.google.com ([209.85.210.44]:60186 "EHLO mail-da0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756774Ab3AHQwo (ORCPT ); Tue, 8 Jan 2013 11:52:44 -0500 Received: by mail-da0-f44.google.com with SMTP id z20so277003dae.17 for ; Tue, 08 Jan 2013 08:52:43 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references:in-reply-to:references; bh=EzRA5vT7y9fnCpJu70ZjwqaB/1nDRD++NvWFTSSBHdY=; b=seEWVPafFk2Hvp1qHR6lRbX/3FhAw7GEWBRBqdGhpt7TAe7+bYhqiAdXZkFOD89aiZ jjIxui1kYGyDtYNQhNYo+uT5TTXMNcTX3h8QXEPh/Su8S9xGhgD/Veej7Oz6U+vGyX6v O2Hy802LwtRpqIgSo2ontu3yIIjfe2HIZCZaIKzAp3K0H2jMrNDBuAhK+gnJJDE0p9Hr 2bKWtRrhsB1nQm3HKI4p0U1Zj6KlIYHDaBx5466a5oQL2yPj1qXBC5oysc8Kuivb0p0N zEVaACRXH2hkolf4r397Dtgt20IpuBxIfLFhPbJ2y7y1jX1VMN69fwud3YumKabooC2/ rcBw== X-Received: by 10.68.234.229 with SMTP id uh5mr200033991pbc.123.1357663963477; Tue, 08 Jan 2013 08:52:43 -0800 (PST) Received: from localhost.localdomain ([120.196.98.117]) by mx.google.com with ESMTPS id f5sm41038922pav.22.2013.01.08.08.52.40 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 08 Jan 2013 08:52:42 -0800 (PST) From: Jiang Liu To: Bjorn Helgaas Cc: Jiang Liu , "Rafael J . Wysocki" , Yijing Wang , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, Yinghai Lu Subject: [PATCH v3 2/6] PCI: split registration of PCI bus devices into two stages Date: Wed, 9 Jan 2013 00:52:21 +0800 Message-Id: <1357663945-16054-3-git-send-email-jiang.liu@huawei.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1357663945-16054-1-git-send-email-jiang.liu@huawei.com> References: <1357663945-16054-1-git-send-email-jiang.liu@huawei.com> In-Reply-To: References: Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When handling BUS_NOTIFY_ADD_DEVICE event for a PCI bridge device, the notification handler can't hold reference count to the new PCI bus because the device object for the new bus (pci_dev->subordinate->dev) hasn't been initialized yet. Split the registration of PCI bus device into two stages as below, so that the event handler could hold reference count to the new PCI bus when handling BUS_NOTIFY_ADD_DEVICE event. 1) device_initialize(&pci_dev->dev) 2) device_initialize(&pci_dev->subordinate->dev) 3) notify BUS_NOTIFY_ADD_DEVICE event for pci_dev 4) device_add(&pci_dev->dev) 5) device_add(&pci_dev->subordinate->dev) Signed-off-by: Jiang Liu Signed-off-by: Yinghai Lu Acked-by: Rafael J. Wysocki --- drivers/pci/bus.c | 2 +- drivers/pci/probe.c | 4 +++- drivers/pci/remove.c | 10 +++++----- 3 files changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index ad6a8b6..2fea481 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -198,7 +198,7 @@ int pci_bus_add_child(struct pci_bus *bus) if (bus->bridge) bus->dev.parent = bus->bridge; - retval = device_register(&bus->dev); + retval = device_add(&bus->dev); if (retval) return retval; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index e557d6f..a8315c2 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -642,6 +642,7 @@ static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, */ child->dev.class = &pcibus_class; dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr); + device_initialize(&child->dev); /* * Set up the primary, secondary and subordinate @@ -1678,7 +1679,8 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus, b->dev.class = &pcibus_class; b->dev.parent = b->bridge; dev_set_name(&b->dev, "%04x:%02x", pci_domain_nr(b), bus); - error = device_register(&b->dev); + device_initialize(&b->dev); + error = device_add(&b->dev); if (error) goto class_dev_reg_err; diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index fc38c48..a1fdd0f 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -48,11 +48,11 @@ void pci_remove_bus(struct pci_bus *bus) list_del(&bus->node); pci_bus_release_busn_res(bus); up_write(&pci_bus_sem); - if (!bus->is_added) - return; - - pci_remove_legacy_files(bus); - device_unregister(&bus->dev); + if (bus->is_added) { + pci_remove_legacy_files(bus); + device_del(&bus->dev); + } + put_device(&bus->dev); } EXPORT_SYMBOL(pci_remove_bus);