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Message-ID: <cca6fd560aa1688ca94fc270310a91ccda9aed06.camel@kernel.crashing.org>
Subject: Re: [PATCH 2/3] nvme: Retrieve the required IO queue entry size
 from the controller
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
        Jens Axboe <axboe@fb.com>, Keith Busch <kbusch@kernel.org>,
        Paul Pawlowski <paul@mrarm.io>
Date:   Tue, 16 Jul 2019 22:17:56 +1000
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On Tue, 2019-07-16 at 14:05 +0200, Christoph Hellwig wrote:
> On Tue, Jul 16, 2019 at 08:58:28PM +1000, Benjamin Herrenschmidt wrote:
> > The main risk is if existing controllers return crap in SQES and we try
> > to then use that crap. The rest should essentially be NOPs.
> > 
> > Maybe I should add some kind of printk to warn in case we use/detect a
> > non-standard size. That would help diagnosing issues.
> 
> Given that the spec currently requires bits 0 to 3 of SQES to be 6
> we might as well not check SQES and just hardcode it to 6 or 7 depending
> on the quirk.  That actually was my initial idea, I just suggested using
> the SQES naming and indexing.

If we're going to do that, then I can move it back to pci.c and leave
core.c alone then I suppose. Up to you. I'm just doing that for fun, no
beef in that game :-) let me know how you want it.

Cheers,
Ben.