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Date: Mon, 24 Feb 2025 15:33:51 +0100
From: Christoph Hellwig <hch@lst.de>
To: Xinyu Zhang <xizhang@purestorage.com>
Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org,
	Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@kernel.dk>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>,
	Caleb Sander Mateos <csander@purestorage.com>
Subject: Re: [PATCH] nvme: map uring_cmd data even if address is 0
Message-ID: <20250224143350.GB1406@lst.de>
References: <20250220235101.119852-1-xizhang@purestorage.com>
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On Thu, Feb 20, 2025 at 04:51:01PM -0700, Xinyu Zhang wrote:
> When using kernel registered bvec fixed buffers, the "address" is
> actually the offset into the bvec rather than userspace address.
> Therefore it can be 0.

How is that actually going to work?  Who is interpreting that address?