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 CF7E0CF07BF for ; Thu, 10 Oct 2024 08:15:00 +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-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=sKWJ3l4GiEI9DusGGHu2Cc0sXMNnncLY7avmubYGgFA=; b=b6xO2ZWo3e+KnIkX/INvCbe32b 28YTlmbQ3cF2KnU3DPiLCuC2BifBBxHTRWVTUxxWh142FXmOtf1T0HblFJGxZDeWO63xLHrzTbKPb HuOE5QNO9FWYDTiLEZ2TxpDFj3UzjKaHSg8k0r/Pg7mpDjMsjIa+3DZhMnC7CywKcTgF9Eb1iYhe0 87k1gfckNWlLyK29yNZbtBnrmuc/nYX5ywItvIY80Us7z7wUrCDMH24H31DfQNXL6ZAFODScQtn6i JgnkgkisQFpl6KFDEh6m0ybNKr7NvArMQzDDiKNi/dknnIQI14ZeF3rKdWxLJ3OWBoq2zga7JHkkn NmFYPdQw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1syoK1-0000000Bw7t-18Qy; Thu, 10 Oct 2024 08:14:57 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1synzn-0000000Bslc-08pR for linux-nvme@lists.infradead.org; Thu, 10 Oct 2024 07:54:04 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 15AD9227A8E; Thu, 10 Oct 2024 09:53:52 +0200 (CEST) Date: Thu, 10 Oct 2024 09:53:51 +0200 From: Christoph Hellwig To: Keith Busch Cc: Christoph Hellwig , Matias =?iso-8859-1?Q?Bj=F8rling?= , dlemoal@kernel.org, cassel@kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, Matias =?iso-8859-1?Q?Bj=F8rling?= Subject: Re: [PATCH 1/2] nvme: make independent ns identify default Message-ID: <20241010075351.GA7525@lst.de> References: <20241008145503.987195-1-m@bjorling.me> <20241008145503.987195-2-m@bjorling.me> <20241009074611.GB16181@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: 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-20241010_005403_246055_E5214332 X-CRM114-Status: GOOD ( 18.28 ) 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 Wed, Oct 09, 2024 at 08:56:32AM -0600, Keith Busch wrote: > On Wed, Oct 09, 2024 at 09:46:11AM +0200, Christoph Hellwig wrote: > > On Tue, Oct 08, 2024 at 04:55:02PM +0200, Matias Bjørling wrote: > > > However, the independent namespace data structure > > > is mandatory for devices that implement features from the 2.0+ > > > specification. Therefore, we can check this data structure first. If > > > unavailable, retrieve the generic attributes from the NVM command set > > > identify namespace data structure. > > > > I'm not a huge fan of this. For pre-2.0 controllers this means > > we'll now send a command that will fail most of them time. And for > > all the cheap low-end consumer device I'm actually worried that they'll > > get it wrong and break something. > > We already send identify commands that we expect may break on pre-2.0 > controllers: the Identify NS Descriptor List. Identify NS Descriptor List is mandatory starting with NVMe 1.3. We only issue it for 1.3 or if the controller advertises supporting multiple command sets.