Re: [PATCH 2/3] nvme: Retrieve the required IO queue entry size from the controller

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

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.