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 881F5C5DF97 for ; Wed, 26 Aug 2026 14:23:51 +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=bkEkjai77PL3VkD9zUJjJ7IcDmioQfb+WhMFmt4sWAk=; b=ep1ltW5YdM2KsfX4CWFpvcda+o t6f39NaJ81/SR4OMb7qnEx4WtSvG5P7TZC0cqYz3zrZmz/0dvFM6EjeNeU+2BwDnG6oImKIPvZklK lrwOZIpnzG7hHKePhadZP8u1EsAeZm+NUnKAXrI7WOoHL+2S3u27pNu6+9INArZ4rICsgG4fYS5vk 7CucVvggytQ4MIyFZHLYsKsGryWo8No1h7XP2XyE55ncQAkhdslRnxhih5f0buuOQ59Itztc6jv8T 28m+u2nuNL5Fc6RdwY1vKZPfl1QVa79tUSs/jFFykjfXNanouUDWXfKAZIESJ7bXW3d6uxqCsc5+X h5/d3Mbg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzEXa-00000002aqm-17eR; Wed, 26 Aug 2026 14:23:46 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wzEXZ-00000002aqe-0B7L for linux-nvme@lists.infradead.org; Wed, 26 Aug 2026 14:23:45 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 7506D41245; Wed, 26 Aug 2026 14:23:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E2121F000E9; Wed, 26 Aug 2026 14:23:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1787754224; bh=bkEkjai77PL3VkD9zUJjJ7IcDmioQfb+WhMFmt4sWAk=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=cHrly7z5HtT8i+OMuv+Ieo/UF3PbQM5PsDqZoifjAtTKP8nzX9lSEnrUdgBt5GnF2 /J5iff3z5BeRtU5TIvBgIgEIPOyJjDcRCMpxnRwCsjHk9yyj3+oMEmymMiKlfBiRub ++Gvj8SWWV5Rg88IUQtW2t+x81SRHpjrkMoxyw5ZXdzt3l6Lgq+TGzz2g6WHgsCFrk uv7ondxGI12EgNscePQZenDJbJnP7BgTHqR5ze0dC6yez8AKk81/R1GdmtVE/oVua2 6lfuDeA2o3+cLSumTKPd2wCNglYRY45z9eGMMJjY8l65ZjB8nzNHhP4mX1ozVNGNpe xR5kEDy8b8EVQ== Date: Wed, 26 Aug 2026 08:23:42 -0600 From: Keith Busch To: Nilay Shroff Cc: wenxiong@linux.ibm.com, 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 06:10:09PM +0530, Nilay Shroff wrote: > when none of those namespaces are actually in use. So for instance, > with this change now, I can't rmmod nvme.ko until I delete > all namespaces/paths created under PCIe nvme subsystem, even though > no one is using the namespace/path under that subsystem. I'd call that a feature. :) > Instead, I think the module reference should track the lifetime of an > active user of the multipath namespace. When the namespace is in use, > the corresponding transport module(s) need to remain loaded and once > the namespace is no longer in use, those references should be released. That's what v1 was trying to do, but it doesn't work. The transports used to reach a namespace may not be the same across the open and close.