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Date:   Fri, 28 Jan 2022 13:36:38 +0100
From:   Daniel Wagner <dwagner@suse.de>
To:     Keith Busch <kbusch@kernel.org>
Cc:     linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [RFC] nvme: Do not reject dynamic controller cntlid
Message-ID: <20220128123638.unxd5fzoctit6lpi@carbon.lan>
References: <20220127133648.8201-1-dwagner@suse.de>
 <20220127171758.GB2266713@dhcp-10-100-145-180.wdc.com>
 <20220128103137.zugnrh2bbhkqpaoz@carbon.lan>
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On Fri, Jan 28, 2022 at 11:31:37AM +0100, Daniel Wagner wrote:
> On Thu, Jan 27, 2022 at 09:17:58AM -0800, Keith Busch wrote:
> > > +static inline bool nvme_ctrl_dynamic(struct nvme_ctrl *ctrl)
> > > +{
> > > +	return ctrl->cntlid == 0xffff;
> > > +}
> > 
> > It's probably safe to assume 0xffff is dynamic, but spec suggests we
> > check ID_CTRL.FCATT bit 0.
> 
> Okay, but this one is only defined for fabrics. I haven't found anything
> so far which is equivalent to FCATT bit 0 for memory based transport.

Never mind. After discussing it with Hannes it turns out there is no
problem here. I didn't understand the spec correctly (it's difficult to
get an exact answer) on this topic.