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Message-ID: <40d9b2ad-2f8a-42c8-54cf-b22e24d78538@canonical.com>
Date:   Tue, 1 Mar 2022 09:49:35 +0100
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Subject: Re: [PATCH v3 01/11] driver: platform: Add helper for safer setting
 of driver_override
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To:     Bjorn Helgaas <helgaas@kernel.org>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Stuart Yoder <stuyoder@gmail.com>,
        Laurentiu Tudor <laurentiu.tudor@nxp.com>,
        Abel Vesa <abel.vesa@nxp.com>, Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        Mathieu Poirier <mathieu.poirier@linaro.org>,
        Vineeth Vijayan <vneethv@linux.ibm.com>,
        Peter Oberparleiter <oberpar@linux.ibm.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Christian Borntraeger <borntraeger@linux.ibm.com>,
        Sven Schnelle <svens@linux.ibm.com>,
        Andy Gross <agross@kernel.org>,
        Srinivas Kandagatla <srinivas.kandagatla@linaro.org>,
        Mark Brown <broonie@kernel.org>,
        "Michael S. Tsirkin" <mst@redhat.com>,
        Jason Wang <jasowang@redhat.com>, linux-kernel@vger.kernel.org,
        linux-clk@vger.kernel.org, NXP Linux Team <linux-imx@nxp.com>,
        linux-arm-kernel@lists.infradead.org, linux-hyperv@vger.kernel.org,
        linux-pci@vger.kernel.org, linux-remoteproc@vger.kernel.org,
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        Linus Torvalds <torvalds@linux-foundation.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>
References: <20220228200326.GA516164@bhelgaas>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
In-Reply-To: <20220228200326.GA516164@bhelgaas>
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On 28/02/2022 21:03, Bjorn Helgaas wrote:
> On Sun, Feb 27, 2022 at 02:52:04PM +0100, Krzysztof Kozlowski wrote:
>> Several core drivers and buses expect that driver_override is a
>> dynamically allocated memory thus later they can kfree() it.
> 
>> +int driver_set_override(struct device *dev, const char **override,
>> +			const char *s, size_t len)
>> +{
>> +	const char *new, *old;
>> +	char *cp;
>> +
>> +	if (!dev || !override || !s)
>> +		return -EINVAL;
>> +
>> +	/* We need to keep extra room for a newline */
> 
> It would help a lot to extend this comment with a hint about where the
> room for a newline is needed.  It was confusing even before, but it's
> much more so now that the check is in a completely different file than
> the "show" functions that need the space.
> 

Indeed, this needs explanation.


Best regards,
Krzysztof