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 2232DCD6E4A for ; Thu, 4 Jun 2026 08:28:54 +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=BvqgnkRf+aKzqJ49qoawoRqNG0mFdAfF6OiDAA1omn8=; b=D2mWNfJSaa6Nwqc+B6RbSFUJmt pMb2AotNEtc42p/hL3HuTpsVCQGGXe3o4CHHohL/jSpgY5O0rze6nAI5F1PYiZ2O3Mvnd99dQuCck Cm9goGdDR56pX+iEDeEuDxkBanSXaLn7/zeGxzAAxjfzg3QvD1FG2bC1+FmTs+ijbqQalOxlvGtKw zeUHN6cOwSEl9aJprS8YtqJVjkWtDlkefE4mvTv9WRmgfsBI+3dDcP5PaUiR5HxqmZyQUfOkB/L8e tKf6Rt2+64i0H7lJXM1RLyzRgR3wrd4ZeAAP/aGOOlL7qQDpjWBz2VNI50tWeUMhS1u7mJ/TSQlxa wQtUZjYg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wV3Ra-0000000GNJc-3KMG; Thu, 04 Jun 2026 08:28:50 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wV3RZ-0000000GNJS-3fDR for linux-nvme@lists.infradead.org; Thu, 04 Jun 2026 08:28:49 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 1745444543; Thu, 4 Jun 2026 08:28:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C58B71F00893; Thu, 4 Jun 2026 08:28:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780561729; bh=BvqgnkRf+aKzqJ49qoawoRqNG0mFdAfF6OiDAA1omn8=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=JGZKXsYQlnoV/OZgfrE8KNT8P5A8KDh60Ifbo/TDvq4dHQrlgyKkJ1y4oPDozNuwi z0jmPqO2zeNyTxYzlExLH7hyTMJuQly2OeS/2Aa8SxE5YxwiblgbgyLzdk5MiZFLsd MNvHmWG63uJu2rr1+iSvkEnYFbKk7vvjLOapzfncAv3FqDpwE47M0O8+O6MsqvvLt7 C0uMruyn5JCezjstu+TjEOtQakVGLRG3iR1RdlH3XbnQrWtdeN8e/QMLvj9QKxNghH nbLJYexsRXgZOgNPDdO0ndh2q+V4XlG8FBbdKVc6xpJ3YN1fxxFHtZK1mMMAV4aipy sA488pE0UXZ/Q== Date: Thu, 4 Jun 2026 09:28:43 +0100 From: Keith Busch To: Shin'ichiro Kawasaki Cc: linux-nvme@lists.infradead.org, Jens Axboe , Christoph Hellwig , Sagi Grimberg , Nilay Shroff Subject: Re: [PATCH v3] nvme-tcp: lockdep: use dynamic lockdep keys per socket instance Message-ID: References: <20260604023208.388157-1-shinichiro.kawasaki@wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260604023208.388157-1-shinichiro.kawasaki@wdc.com> 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 Thu, Jun 04, 2026 at 11:32:08AM +0900, Shin'ichiro Kawasaki wrote: > When NVMe-TCP controller setup and teardown are repeated with lockdep > enabled, lockdep reports false positives WARN for the following locks: > > 1) &q->elevator_lock : IO scheduler change context > 2) &q->q_usage_counter(io) : SCSI disk probe context > 3) fs_reclaim : CPU hotplug bring-up context > 4) cpu_hotplug_lock : socket establishment context > 5) sk_lock-AF_INET-NVME : MQ sched dispatch context for the socket > 6) set->srcu : NVMe controller delete context > > The lockdep WARN was observed by running blktests test case nvme/005 for > tcp transport on v7.1-rc1 kernel with a patch. Refer to the Link tag for > the details of the WARN. > > This is a false positive because lockdep confuses lock 4) (socket > establishment) with lock 5) (socket in use) for different socket > instances. The locks belong to different sockets, but lockdep treats > them as the same due to shared static lockdep keys. Thanks, applied to nvme-7.2.