Received: by 2002:ac0:8c8e:0:0:0:0:0 with SMTP id r14csp385214ima; Wed, 6 Feb 2019 01:33:27 -0800 (PST) X-Google-Smtp-Source: AHgI3IYVIKFz2uHYIP38+C5Z9izfpaf4s4AkWIU8LijyfoM7BMukN0cN4ezWzHsJplgUUh/hTm7a X-Received: by 2002:a17:902:9a9:: with SMTP id 38mr9670191pln.204.1549445607437; Wed, 06 Feb 2019 01:33:27 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1549445607; cv=none; d=google.com; s=arc-20160816; b=PXmDHIkMeA8ApyrGkKYwWKLk1PEWh+5ngQDhTTtxAoOAr/KT/sGS1Skbdz7abdXfLa yie6P1rz1d2ooGSnMWYk2+q3d5IIUxlYrKeNdZyLJfRF1GaTVexmyJmMa6H0qJqiMM5z oyP0AKH5FFmxiImZ85Cf7f8IptxvefwNir/gTqhKHyoxstkCgi1XC3/dQjCpk7nOHSAK hhM3l13QuyY6GRCnDiZKgBIsMxjh9MfBSN8LtjI1lQK5nTYCU9s1NShZ891hV2Xb0NNR 2J5wbXhqhYelZLMGwi0JMx4P/7C/6PvmXEotVu+3wPfS18aAmwHAsOmz9SV686LyO+w2 22yg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:in-reply-to :mime-version:user-agent:date:message-id:from:cc:references:to :subject; bh=sfI1d25yWAdX70QDHc8+KTLKvA/5sjGkjfNsmqbr3As=; b=LfIdDOjFh1LxzuqpMEAyXEmoiioyn6a/NcZ71RY+Uz3CojhzcSyaivdAp8EG4auDZZ Bxoez4cmRALwVDcEjeWQdRTglHqqU/SWTfajE5t1fXxLmZYLu239eay1JCjCsGg241gn 8Laox0VgHfTEVKG20KaXGjLt1zq6xYGmGdeVjCgI4qphVNPj0WrMOT/W3IlSKKUjDkVq sCrpg9lePToWqq46gNJar/cDYrbKvqbn/hUpiDGpcmsO4JbHz5Hidh2Pe3XDCfaPADM2 wmTBo2KTNpxIWs6wyl2T7YdsMRr25/9ab+Xzapp55y/xKTmwJB+Msc7cB7qnv0xNgHAl Pcfg== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id z136si5111630pgz.28.2019.02.06.01.33.11; Wed, 06 Feb 2019 01:33:27 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728426AbfBFJWA (ORCPT + 99 others); Wed, 6 Feb 2019 04:22:00 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:57044 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725897AbfBFJV7 (ORCPT ); Wed, 6 Feb 2019 04:21:59 -0500 Received: from DGGEMS411-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 906D96BC16970496FCFD; Wed, 6 Feb 2019 17:21:57 +0800 (CST) Received: from [127.0.0.1] (10.202.227.238) by DGGEMS411-HUB.china.huawei.com (10.3.19.211) with Microsoft SMTP Server id 14.3.408.0; Wed, 6 Feb 2019 17:21:48 +0800 Subject: Re: Question on handling managed IRQs when hotplugging CPUs To: Christoph Hellwig References: <20190129172059.GC17132@localhost.localdomain> <3fe63dab-0791-f476-69c4-9866b70e8520@huawei.com> <86d5028d-44ab-3696-f7fe-828d7655faa9@huawei.com> <745609be-b215-dd2d-c31f-0bd84572f49f@suse.de> <42d149c5-0380-c357-8811-81015159ac04@huawei.com> <20190205145244.GB28023@localhost.localdomain> <20190205182325.GA3302@lst.de> CC: Keith Busch , Hannes Reinecke , Thomas Gleixner , Marc Zyngier , "axboe@kernel.dk" , Peter Zijlstra , Michael Ellerman , Linuxarm , "linux-kernel@vger.kernel.org" , "Hannes Reinecke" , "linux-scsi@vger.kernel.org" , "linux-block@vger.kernel.org" From: John Garry Message-ID: <3413b0b1-cb3f-3b09-106d-89cf8be30178@huawei.com> Date: Wed, 6 Feb 2019 09:21:40 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <20190205182325.GA3302@lst.de> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.202.227.238] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/02/2019 18:23, Christoph Hellwig wrote: > On Tue, Feb 05, 2019 at 03:09:28PM +0000, John Garry wrote: >> For SCSI devices, unfortunately not all IO sent to the HW originates from >> blk-mq or any other single entity. > > Where else would SCSI I/O originate from? Please note that I was referring to other management IO, like SAS SMP, TMFs, and other proprietary commands which the driver may generate for the HBA - https://marc.info/?l=linux-scsi&m=154831889001973&w=2 discusses some of them also. Thanks, John > > . >