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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 50D1EC35274 for ; Mon, 18 Dec 2023 05:56:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=UUXH1B0SukaVB7Ivk+IiTZ/ygtclQ3AjgdZg3muhjaQ=; b=gXM8zOPuP/NllnhdtYJBP9fQkA d7oMaYguGcqx5GBPHAZpJGu8GSnos7jJVJmj8lJUOd7nZudOm0uAxv3Wo60c2tIsSrrI1hLpiUlyA vIgwEr+7xvpEDW+r5yh2/KcxDI6Ek3MCokkkWXaUxfiUpDbpawkUxANoENn5QR14YUHnhzDCzsfXf zE1uTAOgkq86J1Owc2vwu/UjIUWZpf4qbGUe4BDZadfMT51EJLDJ6gMH2tg5qETL4aTnSEzAzaQOy Q+pfBKYWFFxw8d3XWRfKtvI1EJYMLqgOj5VuEp1r9o2Z3bf4d20m7GrW7rCv5VOkoAZrPTmYfXxj0 DE6hn+JA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rF6cL-009ALB-02; Mon, 18 Dec 2023 05:56:41 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1rF6cF-009AKo-37 for linux-nvme@lists.infradead.org; Mon, 18 Dec 2023 05:56:37 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 1890F68BFE; Mon, 18 Dec 2023 06:56:29 +0100 (CET) Date: Mon, 18 Dec 2023 06:56:28 +0100 From: Christoph Hellwig To: Guixin Liu Cc: james.smart@broadcom.com, kbusch@kernel.org, axboe@kernel.dk, hch@lst.de, sagi@grimberg.me, linux-nvme@lists.infradead.org Subject: Re: [PATCH] nvme: validate maxcmd before use it Message-ID: <20231218055628.GA16928@lst.de> References: <1702629808-96718-1-git-send-email-kanie@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1702629808-96718-1-git-send-email-kanie@linux.alibaba.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231217_215636_151452_CDF4D3F0 X-CRM114-Status: GOOD ( 13.61 ) 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: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Fri, Dec 15, 2023 at 04:43:28PM +0800, Guixin Liu wrote: > According to the NVMe specification, if the 'maximum outstanding > commands' (maxcmd) field is not utilized, it must be set to 0h. > When a host connects to a target that does not employ the maxcmd > field, the queue size (sqsize) gets set to an excessively large > value due to the calculation (u16)(0 - 1) = 65535. > As a result, such a misconfiguration leads to the failure of the > connection establishment. MAXCMD is mandatory for Fabrics.