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=-10.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 EEFA4C433DB for ; Tue, 16 Mar 2021 06:25:30 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 7CD7C6512A for ; Tue, 16 Mar 2021 06:25:30 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7CD7C6512A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=grimberg.me 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=desiato.20200630; h=Sender:Content-Type: Content-Transfer-Encoding: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:Cc:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=55pmJlWOpQEKUb3tauKtezQWGf8YprHiiPMpoHQRj6s=; b=AS2hIAvpXnKFtSQ4Tv7KA+d6o Y9xgEJ6aLnLuhK3IY5sAmXS45YjyJ+P8/AdaNqYaH7HDEPPgCp93lkEkiTJVM3iABJjJyjbkBzn/a qJpC9NfRy6CZ9sKTs5M5un5c7/02gXqh6oXr/PR9Q8br2xuBsts0v54ZSY19XFau/YK16Nk/5iLwg 2STcdnPRwf3tbH0zle3VzKVe4QBstu42rTcJ3nyX6A14QAUPcUqU/+7f2la568dNxzgXYfvbPOM72 Vm22oVFiRplTxYdlxO93A14wkrWfgFA8OntK3+uIL2Dd5YL7TQzywlxCgdiNVkgmjiFfjsh5eyGBu 4/ESbvK3g==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lM38l-00HWN9-Lh; Tue, 16 Mar 2021 06:25:15 +0000 Received: from mail-pl1-f172.google.com ([209.85.214.172]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lM38g-00HWM3-De for linux-nvme@lists.infradead.org; Tue, 16 Mar 2021 06:25:12 +0000 Received: by mail-pl1-f172.google.com with SMTP id z5so16473711plg.3 for ; Mon, 15 Mar 2021 23:25:10 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Oki2GfJKqKRENCr2h9Az2XkzYNX47g6g3fCktpCEJQw=; b=P/mcp4mct9heK8Zw0gH2iZnr8+mXhO3d5g1JmsQeFL0X1bUrnjMZn+0yfjlhE7oIdq nzfTEuzxg37FRJRvQQ63kG26vI/xVWT5V1ztEUxHAuAGt/FOVfcGtEunO3hYWW8Wztsb XMrd/E7fhdgfTgRFScMdZteNHN5HT/S6kBB0m+NYZXzGOlciuJw0gA+BHwC57v2u92WY HKeIw81Q75YXH3FGVr2rbJaNFhOH+qQ/Lkg+g6X3O9bqoHWAiXvPKMH38DHhUndNqodE 7hhoCnlbUe5+m+uJjU/nT/hO3jTDml6mnK+rjtSKhT/T5Bf8//VaIlDeZLCykb9YOn4o 2Gxg== X-Gm-Message-State: AOAM531fLJvWX/zWZiOozVsJEj+dSwfyaHMBdQSamzNWREIH4uw5g64h y3/y7YUFquZTH80GpDeH3BM= X-Google-Smtp-Source: ABdhPJyoPf75cZSg4/uIth3U8j3Fwq/Fcqs2VyvRlf+/sdvbbWee6LyOOyl168nGRWFHRDwoMvT0Tw== X-Received: by 2002:a17:90a:c08a:: with SMTP id o10mr3174717pjs.67.1615875908882; Mon, 15 Mar 2021 23:25:08 -0700 (PDT) Received: from ?IPv6:2601:647:4802:9070:52e4:89ef:d916:a3a6? ([2601:647:4802:9070:52e4:89ef:d916:a3a6]) by smtp.gmail.com with ESMTPSA id r1sm1610861pjo.26.2021.03.15.23.25.07 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 15 Mar 2021 23:25:08 -0700 (PDT) Subject: Re: [PATCH 0/3 rfc] Fix nvme-tcp and nvme-rdma controller reset hangs To: Chao Leng , linux-nvme@lists.infradead.org, Christoph Hellwig , Keith Busch , Chaitanya Kulkarni References: <20210315222714.378417-1-sagi@grimberg.me> <7d552635-6f95-fca4-b0ca-709967465495@huawei.com> <3a172ebf-eeb8-b7a0-4eb2-099fa74bc1c6@grimberg.me> From: Sagi Grimberg Message-ID: Date: Mon, 15 Mar 2021 23:25:07 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210316_062510_514698_4241DAF9 X-CRM114-Status: GOOD ( 12.71 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 >>> We also found Similar deadlocks in the older version. >>> However, with the latest code, it do not block grabbing the nshead srcu >>> when ctrl is freezed. >>> related patches: >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/block/blk-core.c?id=fe2008640ae36e3920cf41507a84fb5d3227435a >>> >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=5a6c35f9af416114588298aa7a90b15bbed15a41 >>> >>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/block/blk-core.c?id=ed00aabd5eb9fb44d6aff1173234a2e911b9fead >>> >>> I am not sure they are the same problem. >> >> Its not the same problem. >> >> When we teardown the io queues, we freeze the namespaces request queues. >> This means that concurrent mpath submit_bio calls can now block with >> the srcu lock taken.What is the call trace of ->submit_bio()? > The requeue work or normal submit bio? Both. submit_bio_noacct will try to get the queue->g_usage_counter (blk_queue_enter), will fail because the queue is frozen, and then will block until the queue unfreeze will wake it up to try again... _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme