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Date:   Fri, 2 Apr 2021 19:16:48 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Niklas Cassel <Niklas.Cassel@wdc.com>
Cc:     Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@fb.com>,
        Christoph Hellwig <hch@lst.de>,
        Sagi Grimberg <sagi@grimberg.me>,
        "minwoo.im.dev@gmail.com" <minwoo.im.dev@gmail.com>,
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        "linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH] nvme: allow NVME_IOCTL_IO_CMD on controller char
 dev even when multiple ns
Message-ID: <20210402171648.GA22651@lst.de>
References: <20210326205943.431185-1-Niklas.Cassel@wdc.com>
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Well, there is at least one good reason for not allowing this
retroactively:

Old users of the ioctl could have complete garbage in the field, and
might send the command to a random namespace now instead of the first
one.

So unles we have a very good reason I think we should keep
NVME_IOCTL_IO_CMD on the controller char dev deprecated and maybe
eventually remove it.