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Date: Fri, 24 Apr 2026 15:24:23 +0200
From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joel Granados <joel.granados@kernel.org>,
	Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@kernel.dk>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Chaitanya Kulkarni <chaitanyak@nvidia.com>,
	linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC 0/5] nvme: Controller Data Queue (CDQ) support
Message-ID: <20260424132423.GA15833@lst.de>
References: <20260424-jag-cdq-lkml-v1-0-d773343a717c@kernel.org> <20260424130615.GW3611611@ziepe.ca>
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User-Agent: Mutt/1.5.17 (2007-11-01)

On Fri, Apr 24, 2026 at 10:06:15AM -0300, Jason Gunthorpe wrote:
> On Fri, Apr 24, 2026 at 01:37:50PM +0200, Joel Granados wrote:
> 
> > There is however, no clear consensus on how NVMe Live Migration should
> > land in the Linux kernel. The 2022 discussion [1] explored a VFIO-based
> > approach but reached no conclusion, likely because the specification was
> > not yet mature.
> 
> Yes it was paused until the spec matures, then I expect it to go
> forward.

And it will happen in the nvme software working group.  Which should be
up an running if Samsung hadn't done everything in the power to torpedo
it.  Because of that I do not exact Samsung to have any major impact in
how this will be implemented in Linux.

Note that we also can't discuss any of this at LSF/MM in public, so
Joel side channel loading it onto the schedule should be removed as well.