From mboxrd@z Thu Jan  1 00:00:00 1970
From: Brian Norris <computersforpeace@gmail.com>
Date: Mon, 19 Jan 2015 17:58:35 +0000
Subject: Re: [PATCH] MTD: Deletion of checks before the function call "iounmap"
Message-Id: <20150119175835.GH9759@ld-irv-0074>
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To: SF Markus Elfring <elfring@users.sourceforge.net>
Cc: kernel-janitors@vger.kernel.org, LKML <linux-kernel@vger.kernel.org>, Julia Lawall <julia.lawall@lip6.fr>, Kyungmin Park <kyungmin.park@samsung.com>, linux-mtd@lists.infradead.org, David Woodhouse <dwmw2@infradead.org>

On Sun, Jan 18, 2015 at 06:08:12PM +0100, SF Markus Elfring wrote:
> From: Markus Elfring <elfring@users.sourceforge.net>
> Date: Sun, 18 Jan 2015 17:30:23 +0100
> 
> The iounmap() function performs also input parameter validation.
> Thus the test around the call is not needed.

Is this guaranteed for all arch'es? I expect that it would be, but I see
that, for instance, ARM allows replaceable iounmap() for
subarchitectures. Also, I see checks for various sorts of static
mappings in ARM and x86; these likely (always?) cover the NULL case, but
they're not always straightforward.

Anyway, I'm essentially saying that I'd like to be 100% sure we have a
guarantee before dropping all these.

> This issue was detected by using the Coccinelle software.

What script? Hand-rolled I guess?

Brian