linux-kernel - Re: [PATCH v2 07/16] dell-smbios: don't return an SMBIOS buffer from dell_smbios_send

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Message-ID: <20160209165027.GA1309@dvhart-mobl5.amr.corp.intel.com>
Date:	Tue, 9 Feb 2016 08:50:27 -0800
From:	Darren Hart <dvhart@...radead.org>
To:	Michał Kępień <kernel@...pniu.pl>
Cc:	Matthew Garrett <mjg59@...f.ucam.org>,
	Pali Rohár <pali.rohar@...il.com>,
	Richard Purdie <rpurdie@...ys.net>,
	Jacek Anaszewski <j.anaszewski@...sung.com>,
	platform-driver-x86@...r.kernel.org, linux-leds@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 07/16] dell-smbios: don't return an SMBIOS buffer from
 dell_smbios_send_request()

On Tue, Feb 09, 2016 at 02:27:36PM +0100, Michał Kępień wrote:
> > > An SMBIOS buffer pointer does not need to be returned by
> > > dell_smbios_send_request(), because SMBIOS call results are stored in
> > > the buffer passed as input.
> > 
> > This should come before 6/16, update the commit message to reflect the module
> > exported buffer (not the one passed as input), or possibly just merge this patch
> > and 6/16 as correcting the use of SMBIOS buffer within the module.
> 
> I have only now noticed that I phrased the commit message for this patch
> rather unfortunately as it inappropriately conveyed my reasoning.  What
> I meant by "the buffer passed as input" was not "the buffer passed as an
> argument to dell_smbios_send_request()", but rather "the buffer passed
> to the SMI handler".  In other words, there is no reason to return a
> buffer from dell_smbios_send_request(), because each caller will simply
> find their output in the same buffer they used to provide input (no
> matter whether the latter is passed as a function argument or accessed
> using a module-wide variable).
> 
> Anyway, as even the above explanation is hardly a stellar demonstration
> of clarity, I believe your idea of resolving this issue may simply be
> the best one, thanks.

In my tree, I reworded this as:

    dell-smbios: don't return an SMBIOS buffer from dell_smbios_send_request()

    An SMBIOS buffer pointer does not need to be returned by
    dell_smbios_send_request(), because SMBIOS call results are stored in
    the buffer exported by the module.

Is that acceptable?

-- 
Darren Hart
Intel Open Source Technology Center