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 10C44EB64D7 for ; Fri, 16 Jun 2023 07:27:31 +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=eTjIy77irMuI3XZjtWd9fTpFOTT6rjGVGWqD+UG2Fho=; b=c7UgUE+aFkXnfsuwz7Zvvs1n9C jT/np3zdZ/i1Kiv8wujhf3uLEnOQeQfpfG4Q+u0Y4v3SAhP859hKke9Kt40z1GYFdu64vSpCZaaXs 7vlydzrWPcFoS0VGtzSt/StoFQxtOky7Oj3BxZEWvUsMgRQYywvCe1Ig5lflnEcnhgP9d2FRs5+BT 4rX7v6a1+ffMSAYaElLU6vvrUPhDeqhOcarhBBBlRKWIFkHu1PbNTHbZ6whw4YHjTXfOv0ff399Mx PL6shBRkWNcGfTlHZ6TvbREpvWFmYW0nwyQT3INlwYDS+9la7jWQVxv1J+s4SVht2qCGF5m/5RBvz U3vimGwQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1qA3rk-00H99x-05; Fri, 16 Jun 2023 07:27:28 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1qA3rh-00H99D-0O for linux-nvme@lists.infradead.org; Fri, 16 Jun 2023 07:27:26 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id BE64F6732D; Fri, 16 Jun 2023 09:27:21 +0200 (CEST) Date: Fri, 16 Jun 2023 09:27:21 +0200 From: Christoph Hellwig To: Ming Lei Cc: Christoph Hellwig , Keith Busch , Jens Axboe , Sagi Grimberg , linux-nvme@lists.infradead.org, Yi Zhang , linux-block@vger.kernel.org, Chunguang Xu Subject: Re: [PATCH 1/4] blk-mq: add API of blk_mq_unfreeze_queue_force Message-ID: <20230616072721.GA30186@lst.de> References: <20230615143236.297456-1-ming.lei@redhat.com> <20230615143236.297456-2-ming.lei@redhat.com> <20230616054800.GA28499@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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-20230616_002725_301421_0139D103 X-CRM114-Status: GOOD ( 20.30 ) 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, Jun 16, 2023 at 03:20:38PM +0800, Ming Lei wrote: > > > > Shouldn't those writebacks be unblocked by the existing check in > > > > bio_queue_enter, test_bit(GD_DEAD, &disk->state))? Or are we missing a > > > > disk state update or wakeup on this condition? > > > > > > GD_DEAD is only set if the device is really dead, then all pending IO > > > will be failed. > > > > del_gendisk also sets GD_DEAD early on. > > No. > > The hang happens in fsync_bdev() of del_gendisk(), and there are IOs pending on > bio_queue_enter(). What is the workload here? If del_gendisk is called to remove a disk that is in perfectly fine state and can do I/O, fsync_bdev should write back data, which is what is exists for. If the disk is dead, we should have called blk_mark_disk_dead before.