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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 0B55FC282CC for ; Wed, 6 Feb 2019 09:22:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D0A082175B for ; Wed, 6 Feb 2019 09:22:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728619AbfBFJWA (ORCPT ); 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 > > . >