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Date: Fri, 14 Jun 2024 02:21:13 +0000
From: Tzung-Bi Shih <tzungbi@kernel.org>
To: Ben Walsh <ben@jubnut.com>
Cc: Dan Carpenter <dan.carpenter@linaro.org>,
	Benson Leung <bleung@chromium.org>,
	Guenter Roeck <groeck@chromium.org>,
	chrome-platform@lists.linux.dev, linux-kernel@vger.kernel.org,
	kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] platform/chrome: cros_ec_lpc: Fix error code in
 cros_ec_lpc_mec_read_bytes()
Message-ID: <ZmupGcjkuU0bNtdl@google.com>
References: <e0b43fb5-ecc8-4fb4-9b76-c06dea8cc4c4@moroto.mountain>
 <87sexgrdk4.fsf@jubnut.com>
 <ZmsvHBrYSpwYLyxx@google.com>
 <87o784ac55.fsf@jubnut.com>
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In-Reply-To: <87o784ac55.fsf@jubnut.com>

On Thu, Jun 13, 2024 at 08:14:14PM +0100, Ben Walsh wrote:
> Tzung-Bi Shih <tzungbi@kernel.org> writes:
> > On Thu, Jun 13, 2024 at 05:51:39PM +0100, Ben Walsh wrote:
> >>   or 2. Put in a check for length == 0.
> >> 
> >>   or 3. Change the logic in `fwk_ec_lpc_mec_in_range`. Although I'm not
> >>   sure what the correct answer is to "zero length is in range?"
> >> 
> >> I prefer option 2. What do you think?
> >
> > How about drop the length check at [2]?
> >
> > [2]: https://elixir.bootlin.com/linux/v6.9/source/drivers/platform/chrome/cros_ec_lpc_mec.c#L44
> >
> 
> This works, but we still end up calling cros_ec_lpc_io_bytes_mec() with
> zero length. Although this seems to work fine, we could put a length
> check at the top of cros_ec_lpc_read_bytes() to avoid it.

I guess you mean: cros_ec_lpc_io_bytes_mec().  Ack.