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 7D1E3C282D7 for ; Wed, 30 Jan 2019 17:36:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A12A21473 for ; Wed, 30 Jan 2019 17:36:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732516AbfA3Rgk (ORCPT ); Wed, 30 Jan 2019 12:36:40 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:45750 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726341AbfA3Rgk (ORCPT ); Wed, 30 Jan 2019 12:36:40 -0500 Received: from DGGEMS408-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 0ED39E9CA0EE24673DC3; Thu, 31 Jan 2019 01:36:38 +0800 (CST) Received: from [127.0.0.1] (10.202.226.43) by DGGEMS408-HUB.china.huawei.com (10.3.19.208) with Microsoft SMTP Server id 14.3.408.0; Thu, 31 Jan 2019 01:36:29 +0800 Subject: Re: [PATCH v2 6/7] scsi: libsas: reset the phy address if discover failed To: Jason Yan , , References: <20190130082412.9357-1-yanaijie@huawei.com> <20190130082412.9357-7-yanaijie@huawei.com> CC: , , , , , , , , , , , , Xiaofei Tan , Ewan Milne , Tomas Henzl From: John Garry Message-ID: Date: Wed, 30 Jan 2019 17:36:20 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <20190130082412.9357-7-yanaijie@huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.226.43] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 30/01/2019 08:24, Jason Yan wrote: > When we failed to discover the device, the phy address is still kept > in ex_phy. So when the next time we revalidate this phy the > address and device type is the same, it will be considered as flutter > and will not be discovered again. So the device will not be brought up. > > Fix this by reset the phy address to the initial value. Then > in the next revalidation the device will be discovered agian. Why fail to discover the device? I wonder in which scenario you have seen this, such that it is worth rediscovery. > > Tested-by: Chen Liangfei > Signed-off-by: Jason Yan > CC: Xiaofei Tan > CC: John Garry > CC: Johannes Thumshirn > CC: Ewan Milne > CC: Christoph Hellwig > CC: Tomas Henzl > CC: Dan Williams > CC: Hannes Reinecke > --- > drivers/scsi/libsas/sas_expander.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c > index 6e56ebdc2148..e781941a7088 100644 > --- a/drivers/scsi/libsas/sas_expander.c > +++ b/drivers/scsi/libsas/sas_expander.c > @@ -1100,6 +1100,13 @@ static int sas_ex_discover_dev(struct domain_device *dev, int phy_id) > i, SAS_ADDR(ex->ex_phy[i].attached_sas_addr)); > } > } > + } else { > + /* if we failed to discover this device, we have to > + * reset the expander phy attached address so that we > + * will not treat the phy as flutter in the next > + * revalidation > + */ > + memset(ex_phy->attached_sas_addr, 0, SAS_ADDR_SIZE); > } > > return res; >