From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793209647; b=CwnMAZHxUpZ9V7P5LmF7K36TAgNiaXJPs2BD5+JvYAwq9d4Rld7HCr42HMZWSZG/5OmD 10W94t/rFwR6jKPadjXmFyAlGEBdOxcuKZMSXJj6d0bI+5iaojZ6ZrGTHJmwgO/oKtM6J HGnHumK2N4y3XQdJNZyncRfYWFqfiFu22czNFZuHxB+H+t0bnmLQBv+lexWHYx4Z4vQ+3 rUxfx8rINa0pSf3UapcaY7cfLuhwoN479r+95z/0gm41VROkzwIKtEmLtgJc9dL21iBnC smZEzL1LPuN7xXRFCXO5eqQ3vlrAxve279rVXDyBNTCYwOenQFcSATXK22/nmKYhpww== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793209647; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition: Content-Transfer-Encoding:In-Reply-To; bh=Khepq3HVmXfGIh7NMXvkdrEul/x4xyGA8jwlNAtrA0I=; b=G2bTLODobBHjGykuqo6g08JhgakwS08VArXNNnzOoX0wOF56VbDdASmyqYjre3GQ1ukP OjrPGfEUiL2M2NKaL/GqToK77RMkQt9g5JLXq2tfzlMsT9+oDLzF+hTl0fCYrdVu4qX9L zkU+6trkKF5v/YjQgahPOX79opsoEuVT9zGaFcgUMyblJaTr4BAWn74+Lu3chnAj+YBbK /pVuIMyO4kUArM/0goctJOn0U5rhtvvofk5FgVejyCKuIRUJRle8pB7ehY1d/TYapvpO3 lYDFocXY95Ko+09qwHQkUgtvrfXBm8fpagquDw2y3VpP9cKIwevyvoyv9aQBbojqkKw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=IECpJTyt; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E41AB606A31A for ; Wed, 28 Oct 2026 17:47:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=IECpJTyt Received: by smtp.kernel.org (Postfix) with ESMTPSA id 70E011F01829; Wed, 28 Oct 2026 17:47:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793209646; bh=Khepq3HVmXfGIh7NMXvkdrEul/x4xyGA8jwlNAtrA0I=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=IECpJTyt2Oz6ZKLCukTSn7AEY5ufZtSzT4CO7RdGh5QIXY+SFHJS4urIF2K7LwVyl I6brUJaboY+FwvTGyiMIUaTLUf8Ja/AhhrYyop0XQWJINBZ4ZuNaoXlDshIXReHdIu CCw5C7HYvJehb4n7xlCgRc8ZZHzjdtS7J47mELeoTqF1IZKt9RgYMCzmTO2wjeShaH Z0buq46H/qzSrgMVfKeLwWonva5yGNxhLybUdlf1TlNWDWDYdxalXdywzOPOmIGbI4 steAtoXXMmsGUamrMBwJWGWOSW8G4Pq2DygAxT8DpqfkUttMw6YiXr3UKYXj1fMn3H FRVnJs7m8L2iA== Date: Wed, 28 Oct 2026 11:47:25 -0600 From: Keith Busch To: Erwan Velu Cc: Erwan Velu , linux-nvme@lists.infradead.org, axboe@kernel.dk, hch@lst.de, sagi@grimberg.me, linux-kernel@vger.kernel.org Subject: Re: [PATCH] nvme: honor the volatile write cache enable state Message-ID: References: <7fec6534-9e57-4041-8699-72c5950c7e2a@criteo.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Wed, Oct 28, 2026 at 06:08:17PM +0100, Erwan Velu wrote: > Le mer. 28 oct. 2026 à 17:08, Keith Busch a écrit : > [...] > > > Considering the performance impact for these type of device,s would you be > > > open to a backport to stable once merged ? > > > > Not sure when a performance improvement is stable worthy. I'm more > > concerned that doing this is going to expose corruption, but it's what > > the device is asking for, so fine to introduce it, but stable is > > questionable. > If we consider this dangerous for this device, should we add a quirk > for some devices that could be seen as lying? Let's just assume spec complaince for now until proven otherwise. When/if a device is discovered to be quirky on this feature, we can introduce handling to ignore WCE.