linux-kernel - Re: [PATCH] wifi: rt2x00: use explicitly signed type for clamping

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Message-ID: <Y08PVnsTw75sHfbg@smile.fi.intel.com>
Date:   Tue, 18 Oct 2022 23:40:54 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     "Jason A. Donenfeld" <Jason@...c4.com>
Cc:     linux-wireless@...r.kernel.org, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Andrew Morton <akpm@...ux-foundation.org>,
        Stanislaw Gruszka <stf_xl@...pl>,
        Helmut Schaa <helmut.schaa@...glemail.com>,
        Kalle Valo <kvalo@...nel.org>
Subject: Re: [PATCH] wifi: rt2x00: use explicitly signed type for clamping

On Tue, Oct 18, 2022 at 02:27:34PM -0600, Jason A. Donenfeld wrote:
> On some platforms, `char` is unsigned, which makes casting -7 to char
> overflow, which in turn makes the clamping operation bogus. Instead,
> deal with an explicit `s8` type, so that the comparison is always
> signed, and return an s8 result from the function as well. Note that
> this function's result is assigned to a `short`, which is always signed.

Why not to use short? See my patch I just sent.

-- 
With Best Regards,
Andy Shevchenko