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bh=5ri51JMHrUhsyawDrOSXF+WzWQ8+V6f2roN/j/66SbI=; b=UFc+8kXijIJ/vi7zxnkNkRIzfmWZ7pnrziCRqHE8qfs2iLJxD8wIR66Z/Ym1V7odS7ky7w Mak7jwgVTdgOMPyEvig0rQn9+xrfErJGhMo0LTDB7XekV3Bdr+i4moz81Sabov+jR6Bpl/ BWCtj2gLtbXSyL5thGbpqFTwP1wWOfpTGrpjwkBVdElQ4868XmfilTLWc07c9dz61d9LZ7 BhnJbJLoEcgiAG00Mj4AArpufJbo4Djsn2/b8jfw/IYih/H6cMzxYsEuiqwFV/j5wwvdWT 2ZBqP5mqAfLviIGq8waUgTAiadwDQIBajJo1Zprfrng5IGyZ1OgWaKeFpQ/+6Q== Date: Tue, 25 Feb 2025 09:08:58 +0100 From: Maxime Chevallier To: "Russell King (Oracle)" Cc: Andrew Lunn , =?UTF-8?B?QmrDuHJu?= Mork , davem@davemloft.net, Jakub Kicinski , Eric Dumazet , Paolo Abeni , Heiner Kallweit , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, thomas.petazzoni@bootlin.com, Florian Fainelli , =?UTF-8?B?S8O2cnk=?= Maincent , Simon Horman , Romain Gantois , Antoine Tenart , Marek =?UTF-8?B?QmVow7pu?= Subject: Re: [PATCH net-next 0/2] net: phy: sfp: Add single-byte SMBus SFP access Message-ID: <20250225090858.0d07cc24@fedora.home> In-Reply-To: <20250224172407.32a2b3f8@fedora> References: <20250223172848.1098621-1-maxime.chevallier@bootlin.com> <87r03otsmm.fsf@miraculix.mork.no> <3c6b7b3f-04a2-48ce-b3a9-2ea71041c6d2@lunn.ch> <87ikozu86l.fsf@miraculix.mork.no> <7c456101-6643-44d1-812a-2eae3bce9068@lunn.ch> <20250224172407.32a2b3f8@fedora> Organization: Bootlin X-Mailer: Claws Mail 4.3.0 (GTK 3.24.43; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeefvddrtddtgdekuddulecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhepfffhvfevuffkjghfohfogggtgfesthejredtredtvdenucfhrhhomhepofgrgihimhgvucevhhgvvhgrlhhlihgvrhcuoehmrgigihhmvgdrtghhvghvrghllhhivghrsegsohhothhlihhnrdgtohhmqeenucggtffrrghtthgvrhhnpeegveeltddvveeuhefhvefhlefhkeevfedtgfeiudefffeiledttdfgfeeuhfeukeenucfkphepvdgrtddumegtsgduleemkegugegtmeelfhdttdemsggtvddumeekkeelleemheegtdgtmegvheelvgenucevlhhushhtvghrufhiiigvpedtnecurfgrrhgrmhepihhnvghtpedvrgdtudemtggsudelmeekugegtgemlehftddtmegstgdvudemkeekleelmeehgedttgemvgehlegvpdhhvghlohepfhgvughorhgrrdhhohhmvgdpmhgrihhlfhhrohhmpehmrgigihhmvgdrtghhvghvrghllhhivghrsegsohhothhlihhnrdgtohhmpdhnsggprhgtphhtthhopedujedprhgtphhtthhopehlihhnuhigsegrrhhmlhhinhhugidrohhrghdruhhkpdhrtghpthhtoheprghnughrvgifsehluhhnnhdrtghhpdhrtghpthhtohepsghjohhrnhesmhhorhhkrdhnohdprhgtphhtthhopegurghvv ghmsegurghvvghmlhhofhhtrdhnvghtpdhrtghpthhtohepkhhusggrsehkvghrnhgvlhdrohhrghdprhgtphhtthhopegvughumhgriigvthesghhoohhglhgvrdgtohhmpdhrtghpthhtohepphgrsggvnhhisehrvgguhhgrthdrtghomhdprhgtphhtthhopehhkhgrlhhlfigvihhtudesghhmrghilhdrtghomh X-GND-Sasl: maxime.chevallier@bootlin.com On Mon, 24 Feb 2025 17:24:07 +0100 Maxime Chevallier wrote: > On Mon, 24 Feb 2025 13:48:19 +0000 > "Russell King (Oracle)" wrote: > > > On Mon, Feb 24, 2025 at 02:31:42PM +0100, Andrew Lunn wrote: > > > > What do you think will be the effect of such a warning? Who is the > > > > target audience? > > > > > > It will act as a disclaimer. The kernel is doing its best with broken > > > hardware, but don't blame the kernel when it does not work > > > correctly.... > > > > Indeed. > > > > > > You can obviously add it, and I don't really care. But I believe the > > > > result will be an endless stream of end users worrying about this scary > > > > warning and wanting to know what they can do about it. What will be > > > > your answer? > > > > > > I agree that the wording needs to be though about. Maybe something > > > like: > > > > > > This hardware is broken by design, and there is nothing the kernel, or > > > the community can do about it. The kernel will try its best, but some > > > standard SFP features are disabled, and the features which are > > > implemented may not work correctly because of the design errors. Use > > > with caution, and don't blame the kernel when it all goes horribly > > > wrong. > > > > I was hoping for something shorter, but I think it needs to be expansive > > so that users can fully understand. Another idea based on your > > suggestion above: > > > > "Please note: > > This hardware is broken by design. There is nothing that the kernel or > > community can do to fix it. The kernel will try best efforts, but some > > features are disabled, other features may be unreliable or sporadically > > fail. Use with caution. Please verify any problems on hardware that > > supports multi-byte I2C transactions." > > > > I think what's missing in this message is some indication about what is > actually wrong with the hardware, so : I realise that I have formulated the sentence above a bit strongly, of course this is a suggestion :) > "Please note: > This SFP cage is accessed via an SMBus only capable of single byte > transactions. Some features are disabled, other may be unreliable or > sporadically fail. Use with caution. There is nothing that the kernel > or community can do to fix it, the kernel will try best efforts. Please > verify any problems on hardware that supports multi-byte I2C transactions." Maxime