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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6454C43334 for ; Tue, 19 Jul 2022 13:21:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238753AbiGSNVu (ORCPT ); Tue, 19 Jul 2022 09:21:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47704 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239655AbiGSNV2 (ORCPT ); Tue, 19 Jul 2022 09:21:28 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6057DCBD25 for ; Tue, 19 Jul 2022 05:37:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1658234262; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=qvqB2ULTeD0f2GX9QuVLUrCzayp94gM6HQvsFtp7g0Y=; b=YeZVLofE3Ma1D+84yqjuOi5EkwcSPQ2toKyGMMxGVwl9kxtJ5UL1DeIXLgWSXJTOD3Upbf 4+uykOSYboM7Muk/jhJTuxJlM6ThUQl1HziqMR/6UNgDuA8L6A7SKn8jdfMm2d5lLdo1f3 7tFxqP3NaGbE3thZfXybYGf+uInWGtE= Received: from mimecast-mx02.redhat.com (mx3-rdu2.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-564-ND3EB5wzOqynH1WRPi1hVw-1; Tue, 19 Jul 2022 08:37:33 -0400 X-MC-Unique: ND3EB5wzOqynH1WRPi1hVw-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id DB0031C068F5; Tue, 19 Jul 2022 12:37:32 +0000 (UTC) Received: from T590 (ovpn-8-16.pek2.redhat.com [10.72.8.16]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D5098141511F; Tue, 19 Jul 2022 12:37:29 +0000 (UTC) Date: Tue, 19 Jul 2022 20:37:23 +0800 From: Ming Lei To: Christoph Hellwig Cc: axboe@kernel.dk, linux-block@vger.kernel.org, ming.lei@redhat.com Subject: Re: [PATCH 2/2] Revert "ublk_drv: fix request queue leak" Message-ID: References: <20220718062928.335399-1-hch@lst.de> <20220718062928.335399-2-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220718062928.335399-2-hch@lst.de> X-Scanned-By: MIMEDefang 2.85 on 10.11.54.7 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Hi Christoph, On Mon, Jul 18, 2022 at 08:29:28AM +0200, Christoph Hellwig wrote: > This was just a rather broken way to paper over a core block layer bug > that is now fixed. > > This reverts commit cebbe577cb17ed9b04b50d9e6802a8bacffbadca. This change will break START_DEV/STOP_DEV, which is supposed to run multiple cycles after the device is added, especially this way can help to implement error recovery from userside, such as one ubq_daemon is crashed/hang, the device can be recovered by sending STOP_DEV/START_DEV commands again after new ubq_daemon is setup. So here we do need separated request_queue/disk, and the model is similar with scsi's, in which disk rebind needs to be supported and GD_OWNS_QUEUE can't be set. Thanks, Ming