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 58EB5C61DBD for ; Wed, 26 Aug 2026 16:36:30 +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=KMZYSoVPpZijmrMcPGBY3UxppQNFJKfh/3dyzCJWHg4=; b=HyXqV0QtNxLiK/8sxFoFmUBEMv QNbwzfQHN3CTxc7Oh4LCWwTzDkNQrmDIj43KShm8OH1SrTmoI/g5sfCr4nJqe8tjP0/siVxk4U4Dt aaM9d101dBUtvlPB49o8nlkvGC++HOoVpI3gU1WFmOrjUL9FTqeLVtppif4QBit/EMmeu0AzmubZF 3nIUzASY2uUWsetOAXbt6gwnFxrV5XyN91esMGSR4h2gGE7WuGPmof+88ejCh2gZxZsjJjeVknSIQ 4ULKrR3wnXHv3H0XFPCGNxgVsKUWjPJom3/WDfMCY0jvxO9GIrMP6kaKjQjfLsyPimALuQ+uTxVdf c5PxsU3g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzGc0-00000002lC0-1jQg; Wed, 26 Aug 2026 16:36:28 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzGbz-00000002lBu-03fc for linux-nvme@lists.infradead.org; Wed, 26 Aug 2026 16:36:27 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 0E1D0618AC; Wed, 26 Aug 2026 16:36:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88CBB1F00ACF; Wed, 26 Aug 2026 16:36:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787762185; bh=KMZYSoVPpZijmrMcPGBY3UxppQNFJKfh/3dyzCJWHg4=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=IVvyU4IxPwg3b4YxS6ie7TZCk11JZsJDdBX8HTkL6ZD8ezHX8BpV3sCLUC230ZAa4 E1jN4vwzFWE4IEnEhRU4AtQksko6hsRXCS1AJhz5/gejEvmE2J4RscY8Y0BmcMlR3c 9bOtxsqKGsV6RGjNudJMKUT2Z0qtYzvYydc63Zry8qSIfqh2M+rkhkr8Zp+lCiepwg X3My6jqJgum7d29XwhVWmyor6ndf5E0KjEIPhsu7rZ0Z59tLdQea05n/uHIA65EXjw DNH+6TSp5v8XGq7J7LVBWO4RfytxFAxIk+3iFPFlOnyd+ivTX5SMOs32NYCLWHO2an RSUb5DNvg7m8A== Date: Wed, 26 Aug 2026 10:36:23 -0600 From: Keith Busch To: Wen Xiong Cc: Nilay Shroff , linux-nvme@lists.infradead.org, gjoyce@linux.ibm.com, wenxiong@us.ibm.com Subject: Re: [PATCH V2] nvme: Add module reference counting for multipath devices Message-ID: References: <20260812223206.720363-1-wenxiong@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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, Aug 26, 2026 at 11:18:16AM -0500, Wen Xiong wrote: > On 2026-08-26 07:40, Nilay Shroff wrote: > > > Also, since a multipath head can have paths through different transports > > , we should not take a reference only to the transport of one > > namespace/path > > found through nvme_find_path(), as was done in v1. Instead, when opening > > the > > head, take a module reference iterating through each controller > > reachable > > from the corresponding NVMe subsystem. This ensures that every transport > > that can service I/O for the active multipath namespace remains loaded > > for > > the duration of its use. > > > I will look into iterating though each controller/each namespace from nvme > subsystem. This is not viable. You can add and remove paths to a namespace at any time such that the transports counted on open are not the namespace's transports on close.