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Date: Thu, 28 Aug 2025 13:05:55 +0100
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Subject: Re: [PATCH] net: ethernet: ti: Prevent divide-by-zero in
 cpts_calc_mult_shift()
To: Miaoqian Lin <linmq006@gmail.com>, Andrew Lunn <andrew+netdev@lunn.ch>,
 "David S. Miller" <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>,
 Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
 Matthias Brugger <matthias.bgg@gmail.com>,
 AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>,
 Thomas Gleixner <tglx@linutronix.de>,
 Grygorii Strashko <grygorii.strashko@ti.com>, netdev@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
 linux-mediatek@lists.infradead.org
References: <20250828092224.46761-1-linmq006@gmail.com>
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From: Vadim Fedorenko <vadim.fedorenko@linux.dev>
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On 28/08/2025 10:22, Miaoqian Lin wrote:
> cpts_calc_mult_shift() has a potential divide-by-zero in this line:
> 
>          do_div(maxsec, freq);
> 
> due to the fact that clk_get_rate() can return zero in certain error
> conditions.

Have you seen this happening in the real environment, or is it just
analysis of the code? I don't see a reason for these "certain error
conditions" to happen...