From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas@monjalon.net>
Subject: Re: [PATCH] dpdk-devbind.py: remove module search corner
	cases
Date: Tue, 02 May 2017 00:01:14 +0200
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References: <1493665749-10733-1-git-send-email-mark.asselstine@windriver.com>
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To: Mark Asselstine <mark.asselstine@windriver.com>
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01/05/2017 21:09, Mark Asselstine:
> The existing code used to search for module files via modinfo has
> several corner cases which can result in it failing where it should be
> successful.
> 
> The call to lower() would cause results returned by 'modinfo' to be
> forced to lowercase, results which were subsequently passed to
> exists() which is case sensitive. This was most likely done to capture
> all variants of failure strings modinfo might return
> (ie. ERROR/Error/error/...)  without thought negative effect to the
> later call to exists(). For many this is a nonissue but if the module
> path included non-lowercase alpha characters, something which is
> easily possible with a non-lowercase kernel-extraversion string, this
> would cause an issue.
> 
> We could move the call to lower() to the check for "error" but this
> still leaves possible corner cases, for modules or module paths with
> 'error' in them.
> 
> Instead we will prevent modinfo's stderr from being used as a "good
> value" for path, meaning we either get a valid path from modinfo, or
> nothing at all. This removes all corner cases.
> 
> Ultimately these preliminary checks are unnecessary as exists() will
> only return True if it is passed a valid path, passing it modinfo's
> stderr would fail. In keeping with the original code, however, we do
> some preliminary checks, but we are now free of corner cases.
> 
> Signed-off-by: Mark Asselstine <mark.asselstine@windriver.com>

Good explanation and good fix.

Applied, thanks and welcome