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Date:   Fri, 29 Mar 2019 10:44:40 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Maximilian Heyne <mheyne@amazon.de>
Cc:     David Woodhouse <dwmw2@infradead.org>, Amit Shah <aams@amazon.de>,
        Keith Busch <keith.busch@intel.com>, Jens Axboe <axboe@fb.com>,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>,
        linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] nvme: add per-device io and admin timeouts
Message-ID: <20190329094440.GA27315@lst.de>
References: <20190329093921.95710-1-mheyne@amazon.de>
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On Fri, Mar 29, 2019 at 09:39:20AM +0000, Maximilian Heyne wrote:
> Some NVMe devices require specific io and admin timeouts that are
> different from the default, for instance local vs. remote storage.
> 
> This patch adds per-device admin and io timeouts to the nvme_ctrl
> structure and replaces all usages of the module parameters in the PCI
> NVMe driver with the per-device timeouts.

I'm not all against a per-controller override, but if you controllers
really _require_ a different timeout this is not the way to go.

Please talk to the nvme technical working group about exposing a
default timeout in the controller as that is the only way to make
these things work out of box.