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 014CF1093187 for ; Fri, 20 Mar 2026 07:59:55 +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=6xKbm0cEn2SfiOEekS5So+OL7BJuAGcqKdJ+U82OGMc=; b=O6IotxlZqIZwKOz9POp2uuEhSo m8MjEYLaG3e0psN60N4kIO8x0NNtgP4FbIgyCk2DAtGk0qPKX/sbOiP7QNtCeL/wy3KiL3wxmGfrK Mvn1aXwfSFNXn0IaGLhern3ed2PFWDfpcxTO/7Wl2NyKMxYb1WKX5MKfgAMtcJOUPDpZW1ovXwKgn eI+owttKEKzdZS4vmjXTLQT/zczVcYSIVJWmUKD5HSeRtzyoiyHQ1w8DcaBplYzSDyeon0ykH4xbU LNt54REfsH6dz3I/r3GckXjwVx8A6zOeFlQk369kH25Pqr9U1EJ8NyB5qUEpH+75bt3trjfuvStrC GSUvbKeA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1w3Ulu-0000000CIuY-0hby; Fri, 20 Mar 2026 07:59:54 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1w3Ulr-0000000CItw-2kFU for linux-nvme@lists.infradead.org; Fri, 20 Mar 2026 07:59:52 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 039936732A; Fri, 20 Mar 2026 08:59:49 +0100 (CET) Date: Fri, 20 Mar 2026 08:59:48 +0100 From: Christoph Hellwig To: Nilay Shroff Cc: linux-nvme@lists.infradead.org, hch@lst.de, kbusch@kernel.org, sagi@grimberg.me, kch@nvidia.com, gjoyce@ibm.com Subject: Re: [PATCH 1/1] nvme-loop: do not cancel I/O and admin tagset during ctrl reset/shutdown Message-ID: <20260320075948.GA14895@lst.de> References: <20260313113856.1366774-1-nilay@linux.ibm.com> <20260313113856.1366774-2-nilay@linux.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260313113856.1366774-2-nilay@linux.ibm.com> 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-20260320_005951_833879_69DF0416 X-CRM114-Status: GOOD ( 13.32 ) 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 Fri, Mar 13, 2026 at 05:08:48PM +0530, Nilay Shroff wrote: > Cancelling the I/O and admin tagsets during nvme-loop controller reset > or shutdown is unnecessary. The subsequent destruction of the I/O and > admin queues already waits for all in-flight target operations to > complete. > > Cancelling the tagsets first also opens a race window. After a request > tag has been cancelled, a late completion from the target may still > arrive before the queues are destroyed. In that case the completion path > may access a request whose tag has already been cancelled or freed, > which can lead to a kernel crash. Please see below the kernel crash > encountered while running blktests nvme/040: Looks good: Reviewed-by: Christoph Hellwig