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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 051B8C10F03 for ; Thu, 25 Apr 2019 06:06:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C007420811 for ; Thu, 25 Apr 2019 06:06:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729440AbfDYGGV (ORCPT ); Thu, 25 Apr 2019 02:06:21 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:7253 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727504AbfDYGGU (ORCPT ); Thu, 25 Apr 2019 02:06:20 -0400 Received: from DGGEMS414-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id EB78C4F7AB050DFD9CA7; Thu, 25 Apr 2019 14:06:16 +0800 (CST) Received: from [127.0.0.1] (10.74.149.191) by DGGEMS414-HUB.china.huawei.com (10.3.19.214) with Microsoft SMTP Server id 14.3.439.0; Thu, 25 Apr 2019 14:06:08 +0800 Subject: Re: [PATCH V2 net-next 08/12] net: hns3: stop schedule reset service while unloading driver To: Neil Horman CC: , , , , , , Peng Li References: <1556103931-64031-1-git-send-email-tanhuazhong@huawei.com> <1556103931-64031-9-git-send-email-tanhuazhong@huawei.com> <20190424135524.GE6661@hmswarspite.think-freely.org> From: tanhuazhong Message-ID: Date: Thu, 25 Apr 2019 14:06:07 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.5.2 MIME-Version: 1.0 In-Reply-To: <20190424135524.GE6661@hmswarspite.think-freely.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.74.149.191] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/4/24 21:55, Neil Horman wrote: > On Wed, Apr 24, 2019 at 07:05:27PM +0800, Huazhong Tan wrote: >> This patch uses HCLGE_STATE_REMOVING/HCLGEVF_STATE_REMOVING flag to >> indicate that the driver is unloading, and we should stop new coming >> reset service to be scheduled, otherwise, reset service will access >> some resource which has been freed by unloading. >> >> Signed-off-by: Huazhong Tan >> Signed-off-by: Peng Li >> --- >> V1->V2: fixes a flag setting error >> --- >> drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c | 4 +++- >> drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c | 4 +++- >> drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.h | 1 + >> 3 files changed, 7 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c >> index 4d5568e..ead8308 100644 >> --- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c >> +++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c >> @@ -2175,7 +2175,8 @@ static void hclge_mbx_task_schedule(struct hclge_dev *hdev) >> >> static void hclge_reset_task_schedule(struct hclge_dev *hdev) >> { >> - if (!test_and_set_bit(HCLGE_STATE_RST_SERVICE_SCHED, &hdev->state)) >> + if (!test_bit(HCLGE_STATE_REMOVING, &hdev->state) && >> + !test_and_set_bit(HCLGE_STATE_RST_SERVICE_SCHED, &hdev->state)) >> schedule_work(&hdev->rst_service_task); >> } >> > > In what use case do you need an extra bit for this? From my read, this work > task only gets scheduled from: > 1) Interrupt handlers > 2) Its own service task > > Based on the fact that you are calling cancel_work_sync(...rst_service_task) > from the pci teardown routine, irqs should all be disabled on your devices > already (meaning interrupts shouldn't schedule it), and cancel_work_sync > guarantees that rearming cant happen from within its own service task. > > Neil > Beside these two cases, when the client detects an error and requests a reset, it will call hclge_reset_event and schedule the reset work task to deal with the request. This may happen after calling cancel_work_sync(...rst_service_task) from the pci teardown routine. Best Regards, Huazhong > > . >