From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 70D4BEEA9 for ; Thu, 6 Mar 2025 15:01:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741273283; cv=none; b=qUjHbBpTouy7g0bZYQaaPKy0akuMWFVRgwQYF5+8AZEWaIsInUVfZlPzkuq7OmfYpJ+17oOg9fbNxk8XSkQ9BdJmEfI4nBmAt/n7132WvGg7VyDBsmFEVaB/It6e+jRc4w5qNMuCnf809TP/a8AAZ69UKyo3pxRSFgp2sZLzk48= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741273283; c=relaxed/simple; bh=jZlvV4iZTdSil+zgfLGfHzpyML/Vo7QSZIW0eHQ6HKQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=OWIY2Vg2UnXwFVbDbLiJt6kMkWoWMYo4XvKjOzvGcygbnpmQvKtUESWM9f0zEi+52A91HzsOYF8DF5K7hfdmW9nRNox4s4s135/xAgiX7VGY3ZRmNDhTAjHHG9zlUNUPFvg3s5RGwqFtjmr+kO1vnczZ7/i21Ws4mxILvoAuPN0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=sU7gRBZB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="sU7gRBZB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36AB7C4CEE0; Thu, 6 Mar 2025 15:01:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741273282; bh=jZlvV4iZTdSil+zgfLGfHzpyML/Vo7QSZIW0eHQ6HKQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=sU7gRBZBqEdXDYByqDmxKuk/FfCYoU2HtU7hdkuZYJ6xwiOp3nhXrsIF++PX4TVnt 2ZQpwJ6VWfPq9yNbrzYpBuHkm9Vgt7TL46FBkJMKAu6yzXxuG+CJzxXMtPvqoWO5CF K75udfwe5iklckYNXUP21uQSYJx8zucM24JmKcO85CYzsXsAzmC2XRBCL8zFjZIoqL yMx8+U2TlZbX4eJzDroPws3lUDIxP77Z1H/9daFpC3QnhRugYNdeFEGkOjIBr6OQVN BOFMhZWYAwlMTydy5uY+RonPGVLTqPZmnYgzkCwNIf+leX8rJ+BhjGj0nsRfdeCgNw fECfkaRK1uD6A== Date: Thu, 6 Mar 2025 08:01:19 -0700 From: Keith Busch To: Christoph Hellwig Cc: Hannes Reinecke , Sagi Grimberg , Nilay Shroff , John Meneghini , bmarzins@redhat.com, Bryan Gurney , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, Marco Patalano , axboe@kernel.dk Subject: Re: [PATCH] nvme: remove multipath module parameter Message-ID: References: <0656b66c-dd9c-495d-b1fc-4f09e763fa66@grimberg.me> <91ae613a-7b56-4ca0-b91c-6bc1eee798b8@suse.de> <20250305141554.GA18065@lst.de> <20250305235119.GB896@lst.de> <20250306000348.GA1233@lst.de> <1ffebf60-5672-4cd0-bb5a-934376c16694@suse.de> <20250306141837.GA21353@lst.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250306141837.GA21353@lst.de> On Thu, Mar 06, 2025 at 03:18:37PM +0100, Christoph Hellwig wrote: > On Thu, Mar 06, 2025 at 08:12:03AM +0100, Hannes Reinecke wrote: > > Single ported. > > There is a range of Samsung NVMe where one is a normal, single ported, > > NVMe, and one with a nearly identical model number reporting CMIC. > > > > Causing _quite_ a lot of confusion with the customer (and L3) when > > used under MD, as for the first hotplug works, for the second ... not so > > much. > > If the device is indeed entirely single ported and Samsung can confirm > the setting is incorret and not easily fixable by a firmware update > we can quirk it. It's not one vendor or device. Making this a quirk is a good way to get the mailing list spammed with requests to add yet another device to a quirk table. Or consider a true multiport PCIe where each port connects to a different host. Each host sees a single port so they're not using multipath capabilities, and the admin wants the MD behavior that removes a disk on hot plug. Or even if one host sees both paths of a multiport PCIe, they still might want that hot plug behavior. The module parameter makes that possible, so some equivalent should be available before removing it.