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Date:   Thu, 20 Aug 2020 18:12:14 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     "Ahmed S. Darwish" <a.darwish@linutronix.de>,
        Keith Busch <kbusch@kernel.org>,
        linux-nvme@lists.infradead.org, Sagi Grimberg <sagi@grimberg.me>,
        Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>,
        linux-kernel@vger.kernel.org
Subject: Re: v5.9-rc1 commit reliably breaks pci nvme detection
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On Thu, Aug 20, 2020 at 11:10:58AM -0600, Jens Axboe wrote:
> To be fair, I've only heard this one complaint about it, so hopefully it's
> not too widespread. I'm on an x86-64 laptop myself with nvme, and it works
> just fine :-)

The cause for this is the weird NVMe of by ones, where 0 in a field
means 1.  So for the overflow to happen you need a controller that
supports USHORT_MAX queue entries.  Which don't seem to be all that
common.