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Date:   Sat, 31 Aug 2019 09:29:11 -0600
From:   Keith Busch <keith.busch@intel.com>
To:     Logan Gunthorpe <logang@deltatee.com>
Cc:     linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>, Jens Axboe <axboe@fb.com>,
        Keith Busch <kbusch@kernel.org>,
        Hannes Reinecke <hare@suse.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>
Subject: Re: [PATCH] nvme-core: Fix subsystem instance mismatches
Message-ID: <20190831152910.GA29439@localhost.localdomain>
References: <20190831000139.7662-1-logang@deltatee.com>
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On Fri, Aug 30, 2019 at 06:01:39PM -0600, Logan Gunthorpe wrote:
> To fix this, assign the subsystem's instance based on the instance
> number of the controller's instance that first created it. There should
> always be fewer subsystems than controllers so the should not be a need
> to create extra subsystems that overlap existing controllers.

The subsystem's lifetime is not tied to the controller's. When the
controller is removed and releases its instance, the next controller
to take that available instance will create naming collisions with the
subsystem still using it.