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 X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 895E8C5517A for ; Wed, 11 Nov 2020 15:04:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1AC95207DE for ; Wed, 11 Nov 2020 15:04:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="TnLjsUQi" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726902AbgKKPEy (ORCPT ); Wed, 11 Nov 2020 10:04:54 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:56245 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726702AbgKKPEx (ORCPT ); Wed, 11 Nov 2020 10:04:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1605107092; 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=pdnxDrJbnGriYJu6lUmTawYA8DwyKEDmav8yDLXk2oY=; b=TnLjsUQirwEBKHyub7r78gxLWdPCyyvr7dYqA31yyPCQAzX9TIg8C+Z6CaAKPjJv0bs+Tp PxdOJ3XD8pwzxNDTo/POk0buL4wUwQI/fEDjs7LiK8sVQPVv0LgYzERf9dA2F3qUJcdd7E 6UVKxBoGbGsTAWsN5dfL8YJYQez5xxU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-441-oUWQ_G-SPlSh4zZtW33d7Q-1; Wed, 11 Nov 2020 10:04:46 -0500 X-MC-Unique: oUWQ_G-SPlSh4zZtW33d7Q-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id C37971074661; Wed, 11 Nov 2020 15:04:41 +0000 (UTC) Received: from T590 (ovpn-12-145.pek2.redhat.com [10.72.12.145]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E73046EF7F; Wed, 11 Nov 2020 15:04:25 +0000 (UTC) Date: Wed, 11 Nov 2020 23:04:21 +0800 From: Ming Lei To: Qian Cai Cc: Sumit Saxena , John Garry , Kashyap Desai , Jens Axboe , "James E.J. Bottomley" , "Martin K. Petersen" , don.brace@microsemi.com, Bart Van Assche , dgilbert@interlog.com, paolo.valente@linaro.org, Hannes Reinecke , Christoph Hellwig , linux-block@vger.kernel.org, LKML , Linux SCSI List , esc.storagedev@microsemi.com, "PDL,MEGARAIDLINUX" , chenxiang66@hisilicon.com, luojiaxing@huawei.com, Hannes Reinecke Subject: Re: [PATCH v8 17/18] scsi: megaraid_sas: Added support for shared host tagset for cpuhotplug Message-ID: <20201111150421.GA611503@T590> References: <0c75b881-3096-12cf-07cc-1119ca6a453e@huawei.com> <06a1a6bde51a66461d7b3135349641856315401d.camel@redhat.com> <8043d516-c041-c94b-a7d9-61bdbfef0d7e@huawei.com> <20201111092743.GC545929@T590> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 11, 2020 at 09:42:17AM -0500, Qian Cai wrote: > On Wed, 2020-11-11 at 17:27 +0800, Ming Lei wrote: > > Can this issue disappear by applying the following change? > > This makes the system boot again as well. OK, actually it isn't necessary to register one new lock key for each hctx(blk_flush_queue) instance, and the current way is really over-kill because there can be lots of hw queues in one system. The original lockdep warning can be avoided by setting one nvme_loop specific lock class simply. If nvme_loop is backed against another nvme_loop, we still can avoid the warning by killing the direct end io chain, or assign another lock class. Will prepare one formal patch tomorrow. Thanks, Ming