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Date:   Fri, 8 Mar 2019 14:26:08 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Sagi Grimberg <sagi@grimberg.me>
Cc:     Johannes Thumshirn <jthumshirn@suse.de>,
        Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>,
        Christoph Hellwig <hch@lst.de>,
        Linux Kernel Mailinglist <linux-kernel@vger.kernel.org>,
        Linux NVMe Mailinglist <linux-nvme@lists.infradead.org>
Subject: Re: [PATCH] nvmet: disable direct I/O when unavailable
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On Mon, Feb 25, 2019 at 01:18:10PM -0800, Sagi Grimberg wrote:
>
>> Frankly, we have a ton of testing related special cases in the kernel.
>>
>> This one is a) simple and small, only 10 LoC, b) far away from the fast
>> path or any other place where it could have any impact on legitimate
>> users and c) it prints an informal message showing you what happened.
>>
>> Sorry but this is a https://xkcd.com/386/ moment.
>
> How about we just fail it with a proper error message and let the
> user set buffered_io instead of trying to get smart here...

Yes, would be my preference.