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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 1464BC433E0 for ; Mon, 1 Feb 2021 08:58:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CC4DF64E41 for ; Mon, 1 Feb 2021 08:58:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232661AbhBAI6F (ORCPT ); Mon, 1 Feb 2021 03:58:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:42290 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232549AbhBAI6E (ORCPT ); Mon, 1 Feb 2021 03:58:04 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 2A994AE42; Mon, 1 Feb 2021 08:57:23 +0000 (UTC) Subject: Re: [PATCH v2] nvme-multipath: Early exit if no path is available To: Chao Leng , Sagi Grimberg , Daniel Wagner Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Jens Axboe , Keith Busch , Christoph Hellwig References: <20210127103033.15318-1-dwagner@suse.de> <20210128075837.u5u56t23fq5gu6ou@beryllium.lan> <69575290-200e-b4a1-4269-c71e4c2cc37b@huawei.com> <20210128094004.erwnszjqcxlsi2kd@beryllium.lan> <675d3cf7-1ae8-adc5-b6d0-359fe10f6b23@grimberg.me> <59cd053e-46cb-0235-141f-4ce919c93f48@huawei.com> <65392653-6b03-9195-f686-5fe4b3290bd2@suse.de> <81b22bbf-4dd3-6161-e63a-9699690a4e4f@huawei.com> <715dd943-0587-be08-2840-e0948cf0bc62@suse.de> <6ceff3cb-c9e9-7e74-92f0-dd745987c943@huawei.com> <114751ac-1f7d-ce5e-12c5-7d6303bdb999@suse.de> From: Hannes Reinecke Message-ID: <47a1b796-9d91-5947-4bac-dd8f397041a3@suse.de> Date: Mon, 1 Feb 2021 09:57:22 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/1/21 9:47 AM, Chao Leng wrote: > > > On 2021/2/1 15:29, Hannes Reinecke wrote:[ .. ] >> Urgh. Please, no. That is well impossible to debug. >> Can you please open-code it to demonstrate where the difference to the >> current (and my fixed) versions is? >> I'm still not clear where the problem is once we applied both patches. > For example assume the list has three path, and all path is not > NVME_ANA_OPTIMIZED: > head->next = ns1; > ns1->next = ns2; > ns2->next = head; > old->next = ns2; > And this is where I have issues with. Where does 'old' come from? Clearly it was part of the list at one point; so what happened to it? Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Maxfeldstr. 5, 90409 Nürnberg HRB 36809 (AG Nürnberg), Geschäftsführer: Felix Imendörffer