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From:   Maxime Ripard <maxime@cerno.tech>
To:     jernej.skrabec@gmail.com, wens@csie.org, samuel@sholland.org,
        mripard@kernel.org
Cc:     Maxime Ripard <maxime@cerno.tech>, dri-devel@lists.freedesktop.org,
        linux-arm-kernel@lists.infradead.org, airlied@linux.ie,
        daniel@ffwll.ch, linux-kernel@vger.kernel.org,
        linux-sunxi@lists.linux.dev
Subject: Re: [PATCH] drm/sun4i: dsi: Prevent underflow when computing packet sizes
Date:   Mon, 15 Aug 2022 09:47:14 +0200
Message-Id: <166054963291.173470.13302885096018416390.b4-ty@cerno.tech>
In-Reply-To: <20220812031623.34057-1-samuel@sholland.org>
References: <20220812031623.34057-1-samuel@sholland.org>
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On Thu, 11 Aug 2022 22:16:23 -0500, Samuel Holland wrote:
> Currently, the packet overhead is subtracted using unsigned arithmetic.
> With a short sync pulse, this could underflow and wrap around to near
> the maximal u16 value. Fix this by using signed subtraction. The call to
> max() will correctly handle any negative numbers that are produced.
> 
> Apply the same fix to the other timings, even though those subtractions
> are less likely to underflow.
> 
> [...]

Applied to drm/drm-misc (drm-misc-fixes).

Thanks!
Maxime