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 F3904C433EF for ; Mon, 25 Apr 2022 08:43:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236519AbiDYIqS (ORCPT ); Mon, 25 Apr 2022 04:46:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232124AbiDYIqQ (ORCPT ); Mon, 25 Apr 2022 04:46:16 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E147183022; Mon, 25 Apr 2022 01:43:12 -0700 (PDT) Received: from fraeml709-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Kmz3y2955z67yLV; Mon, 25 Apr 2022 16:40:30 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml709-chm.china.huawei.com (10.206.15.37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 25 Apr 2022 10:43:10 +0200 Received: from [10.47.92.213] (10.47.92.213) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2375.24; Mon, 25 Apr 2022 09:43:09 +0100 Message-ID: <380af884-94f2-231b-040b-2d89a544b8ed@huawei.com> Date: Mon, 25 Apr 2022 09:43:08 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 Subject: Re: [PATCH 4/4] scsi: hisi_sas: Use libsas internal abort support To: Hannes Reinecke , , , , CC: , , , , , , , References: <1646309930-138960-1-git-send-email-john.garry@huawei.com> <1646309930-138960-5-git-send-email-john.garry@huawei.com> From: John Garry In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.47.92.213] X-ClientProxiedBy: lhreml702-chm.china.huawei.com (10.201.108.51) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/04/2022 13:29, Hannes Reinecke wrote: > On 3/3/22 13:18, John Garry wrote: >> Use the common libsas internal abort functionality. >> >> In addition, this driver has special handling for internal abort >> timeouts - >> specifically whether to reset the controller in that instance, so extend >> the API for that. >> > Huh? Is there a reason _not_ to reset the controller once abort times out? There's a bug in v2 HW where the internal abort may timeout due to HW bug but it is not fatal, i.e. the HW state is not totally buggered, so can continue without a reset. > And why isn't that delegated to SCSI EH? For sure, SCSI EH will reset the host if all else fails. However, it may take some time to get to the point of deciding to reset - including lots of timeouts. To accelerate this, we set a host flag to say that we have a HW fault, and don't bother with nexus reset, LU reset, etc. once the initial task abort fails due to HW fault and fail straight away. Maybe the core code could do something similar but it seems messy/hard to generalise. Thanks, John