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Date: Fri, 16 Oct 2026 11:55:11 -0600
From: Keith Busch <kbusch@kernel.org>
To: Erwan Velu <erwanaliasr1@gmail.com>
Cc: linux-nvme@lists.infradead.org, axboe@kernel.dk, hch@lst.de,
	sagi@grimberg.me, linux-kernel@vger.kernel.org,
	Erwan Velu <e.velu@criteo.com>
Subject: Re: [PATCH] nvme: honor the volatile write cache enable state
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On Fri, Oct 16, 2026 at 07:43:24PM +0200, Erwan Velu wrote:
> This disk is configured by default with VWC_PRESENT enabled, but the
> Volatile Write Cache is disabled (NVME_FEAT_VWC_ENABLE=0), so the
> device has a Volatile Write Cache, but it's disabled.

...

> In this table, with my patch, I've enabled and disabled the volatile
> write cache using nvme set-feature -f 6; this only affects
> NVME_FEAT_VWC_ENABLE, and VWC_PRESENT is still reported as present.

...

> Hope that's make it more clear,

Unfortunately, no: there are contradicting statements here.