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Date: Wed, 9 Oct 2024 09:48:05 +0200
From: Christoph Hellwig <hch@lst.de>
To: Matias =?iso-8859-1?Q?Bj=F8rling?= <m@bjorling.me>
Cc: kbusch@kernel.org, hch@lst.de, dlemoal@kernel.org, cassel@kernel.org,
	linux-nvme@lists.infradead.org, linux-block@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Matias =?iso-8859-1?Q?Bj=F8rling?= <matias.bjorling@wdc.com>
Subject: Re: [PATCH 2/2] nvme: add rotational support
Message-ID: <20241009074805.GC16181@lst.de>
References: <20241008145503.987195-1-m@bjorling.me> <20241008145503.987195-3-m@bjorling.me>
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On Tue, Oct 08, 2024 at 04:55:03PM +0200, Matias Bjørling wrote:
> +	if (info->is_rotational)
> +		lim.features |= BLK_FEAT_ROTATIONAL | BLK_FEAT_ADD_RANDOM;

Entropy from block devices is pretty useless.  The only reason we still
keep it for SCSI is because of retro-computing platforms without a proper
platform hardware RNG.  NVMe HDDs reall should not show up in those kinds
of environments.  Also without a add_disk_randomness in the nvme I/O
completion handler this won't actually do anything.