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Date:   Fri, 1 Jun 2018 18:09:54 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Hugo Lefeuvre <hle@owl.eu.com>
Cc:     kernelnewbies@kernelnewbies.org, devel@driverdev.osuosl.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: pi433: add rw semaphore fixing concurrency
 issues
Message-ID: <20180601160954.GA4895@kroah.com>
References: <20180601125037.GA2339@hle-laptop.local>
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On Fri, Jun 01, 2018 at 08:50:37AM -0400, Hugo Lefeuvre wrote:
> Add a rw semaphore fixing potential NULL pointer dereferences in the
> pi433 driver.

Unless you can measure the performance difference, do not use a rw
semaphore, just use a normal mutex please.  Odds are it will be faster
in the end and take up less space.

So please test, or if you can't test, just use a mutex.

thanks,

greg k-h