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=-5.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 21679C433E0 for ; Wed, 24 Feb 2021 07:21:19 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8292164ECB for ; Wed, 24 Feb 2021 07:21:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8292164ECB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=v2+B/30YDWbI5+EC/peY3Y8VAbRehqIS4jZvmveMuFA=; b=UuzLHJfqivle+PuTXs5TzYUS/ ezDTydR6TqZwgMn9a0tVJgNXTxk1wtBP/RVcIzIbh1RWdwFOSd3laRfY0wSPtCjobs43TySC+mUO0 vQMRoqekXbRb7UZNlAdNWsM5Eb7Tqpoc+2jfnjahRfVytbBKpp7u4YGTbXThVj3cuHOMHgLSmg9QC 4QRgdgGYrGZY75TTo/PXdCYCtmgBn9uYCd1Jrv9YjvCLVYqwUdvO8x/xPJMYoAXznDQgD+R+Wos2z cSN/0VgVAQ4+PbpXu4E+oF7eg6p6Qnpwl/cN31iXMGRRR640plEpxJ2Qd6NAY6/N8OetUYeZ9lJyO hAICf+eeg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lEoTq-0007OH-QV; Wed, 24 Feb 2021 07:21:06 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1lEoTo-0007Nq-8B for linux-nvme@lists.infradead.org; Wed, 24 Feb 2021 07:21:05 +0000 Received: from DGGEMM401-HUB.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4DlnNh69jbzYCTb; Wed, 24 Feb 2021 15:19:32 +0800 (CST) Received: from dggema772-chm.china.huawei.com (10.1.198.214) by DGGEMM401-HUB.china.huawei.com (10.3.20.209) with Microsoft SMTP Server (TLS) id 14.3.498.0; Wed, 24 Feb 2021 15:20:59 +0800 Received: from [10.169.42.93] (10.169.42.93) by dggema772-chm.china.huawei.com (10.1.198.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2106.2; Wed, 24 Feb 2021 15:20:58 +0800 Subject: Re: [PATCH 0/2] nvme: sanitize KATO handling To: Hannes Reinecke , Christoph Hellwig References: <20210223120728.104699-1-hare@suse.de> <36e3bfd8-0c69-7540-c9f2-fd37070dc107@huawei.com> <06e3b90a-719e-9561-5c63-67dac0a782e1@suse.de> From: Chao Leng Message-ID: <1834a11c-c472-e14f-ece3-a96ec2ced044@huawei.com> Date: Wed, 24 Feb 2021 15:20:57 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <06e3b90a-719e-9561-5c63-67dac0a782e1@suse.de> Content-Language: en-US X-Originating-IP: [10.169.42.93] X-ClientProxiedBy: dggeme710-chm.china.huawei.com (10.1.199.106) To dggema772-chm.china.huawei.com (10.1.198.214) X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210224_022104_903257_61715A32 X-CRM114-Status: GOOD ( 13.34 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Keith Busch , Daniel Wagner , linux-nvme@lists.infradead.org, Sagi Grimberg Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On 2021/2/24 15:06, Hannes Reinecke wrote: > On 2/24/21 7:42 AM, Chao Leng wrote: >> >> >> On 2021/2/23 20:07, Hannes Reinecke wrote: >>> Hi all, >>> >>> one of our customer had been running into a deadlock trying to terminate >>> outstanding KATO commands during reset. >>> Looking closer at it, I found that we never actually _track_ if a KATO >>> command is submitted, so we might happily be sending several KATO commands >>> to the same controller simultaneously. >> Can you explain how can send KATO commands simultaneously? > > Sure. > Call nvme_start_keep_alive() on a dead connection. > Just _after_ the KATO request has been sent, > call nvme_start_keep_alive() again. Call nvme_start_keep_alive() again? why? Now just nvme_start_ctrl call nvme_start_keep_alive(). The ka_work will be canceled sync before start reconnection. Did I miss something? > > You now have an expired KATO command, and the new KATO command, both are active and sent to the controller. > > Cheers, > > Hannes _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme