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Date:   Tue, 5 Feb 2019 19:23:25 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     John Garry <john.garry@huawei.com>
Cc:     Keith Busch <keith.busch@intel.com>,
        Hannes Reinecke <hare@suse.de>,
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Subject: Re: Question on handling managed IRQs when hotplugging CPUs
Message-ID: <20190205182325.GA3302@lst.de>
References: <20190129172059.GC17132@localhost.localdomain> <3fe63dab-0791-f476-69c4-9866b70e8520@huawei.com> <alpine.DEB.2.21.1901301338170.5537@nanos.tec.linutronix.de> <86d5028d-44ab-3696-f7fe-828d7655faa9@huawei.com> <745609be-b215-dd2d-c31f-0bd84572f49f@suse.de> <alpine.DEB.2.21.1902012255550.8200@nanos.tec.linutronix.de> <d93ff049-e96d-36ce-7e58-ec97cbb27ed0@suse.de> <42d149c5-0380-c357-8811-81015159ac04@huawei.com> <20190205145244.GB28023@localhost.localdomain> <d4a04c13-b7db-84df-b1d3-90022905c084@huawei.com>
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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?