From patchwork Wed Nov 14 12:27:19 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yijing Wang X-Patchwork-Id: 1741121 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: X-Original-To: patchwork-linux-pci@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 54849DF264 for ; Wed, 14 Nov 2012 12:28:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161215Ab2KNM2V (ORCPT ); Wed, 14 Nov 2012 07:28:21 -0500 Received: from szxga01-in.huawei.com ([119.145.14.64]:54648 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161213Ab2KNM2V (ORCPT ); Wed, 14 Nov 2012 07:28:21 -0500 Received: from 172.24.2.119 (EHLO szxeml211-edg.china.huawei.com) ([172.24.2.119]) by szxrg01-dlp.huawei.com (MOS 4.3.4-GA FastPath queued) with ESMTP id ASU14349; Wed, 14 Nov 2012 20:28:11 +0800 (CST) Received: from SZXEML454-HUB.china.huawei.com (10.82.67.197) by szxeml211-edg.china.huawei.com (172.24.2.182) with Microsoft SMTP Server (TLS) id 14.1.323.3; Wed, 14 Nov 2012 20:28:10 +0800 Received: from localhost (10.135.76.84) by SZXEML454-HUB.china.huawei.com (10.82.67.197) with Microsoft SMTP Server id 14.1.323.3; Wed, 14 Nov 2012 20:28:00 +0800 From: Yijing Wang To: Bjorn Helgaas CC: Huang Ying , , Hanjun Guo , , Yijing Wang Subject: [PATCH v5 2/5][RESEND] PCI/AER: use list_for_each_entry to avoid a small race condition window Date: Wed, 14 Nov 2012 20:27:19 +0800 Message-ID: <1352896042-11832-3-git-send-email-wangyijing@huawei.com> X-Mailer: git-send-email 1.7.11.msysgit.1 In-Reply-To: <1352896042-11832-1-git-send-email-wangyijing@huawei.com> References: <1352896042-11832-1-git-send-email-wangyijing@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.135.76.84] X-CFilter-Loop: Reflected Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When we rmmod aer_inject module, there is a small race condition window between pci_bus_ops_pop() and pci_bus_set_ops() in aer_inject_exit, eg. pci_read_aer/pci_write_aer was called between them. So keep pci_bus_ops_list until pci_bus_set_ops complete, use list_for_each_entry() instead of pci_bus_ops_pop to get bus_ops. Signed-off-by: Yijing Wang --- drivers/pci/pcie/aer/aer_inject.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pcie/aer/aer_inject.c b/drivers/pci/pcie/aer/aer_inject.c index fdab3bb..f499f01 100644 --- a/drivers/pci/pcie/aer/aer_inject.c +++ b/drivers/pci/pcie/aer/aer_inject.c @@ -543,10 +543,11 @@ static void __exit aer_inject_exit(void) misc_deregister(&aer_inject_device); - while ((bus_ops = pci_bus_ops_pop())) { + list_for_each_entry(bus_ops, &pci_bus_ops_list, list) pci_bus_set_ops(bus_ops->bus, bus_ops->ops); + + while ((bus_ops = pci_bus_ops_pop())) kfree(bus_ops); - } spin_lock_irqsave(&inject_lock, flags); list_for_each_entry_safe(err, err_next, &einjected, list) {