From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 0CA42CA0FFE for ; Thu, 28 Aug 2025 17:23:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=4lf9KRuU3XqjH9s/P98ePLTJLe34Mktbt6oDMXgNk/4=; b=PkGHrEMXcgiGrPtelfJX6/pvrz 1Z1Op1aSXjySYFyjMFwyJxSYThPgO2x3qw1PSfL9iu7K5FlloLqssVGS1h47apR31obvxctDKGAbX jMC/SycKw6LB3FkXSEk2yhcrdhWkyEbYui6JGKdcMt1XS4z73nBquaZ99PxbkviPFU4t2A+bWu2jZ D2blAXBgqLqGJ3Rl/d1fF4jYIrq1X8IkvyFeJSNHTybDK8PlZH2cjwrACOWxxkcsX6znVq97PuUoz Z7fHm3Zn6MW5Tk7g6V8jCtnuKrz+kwV4ANJBOYBp9cJfb/d/fMqP2nW0bbfRJd52EJwnD5hh9532R 7wkQgm4Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1urgLl-00000002Q7A-2eA6; Thu, 28 Aug 2025 17:23:49 +0000 Received: from out-186.mta1.migadu.com ([95.215.58.186]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1urbOK-00000001RXy-2rW4; Thu, 28 Aug 2025 12:06:10 +0000 Message-ID: <11d46e56-b8d9-4776-9969-d3767d8cda41@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1756382764; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4lf9KRuU3XqjH9s/P98ePLTJLe34Mktbt6oDMXgNk/4=; b=xClLXYSf4+Y47SMAxpPCJbn6XmGzs3dIcquE8NJLfEPLm3/qz+X/1yTkBgXhVxika8ThH3 lsRaGUbO+SUI5mHC1mu87EeBMwd5zKFveKVZbK3cxJCrFE1pNVIWRmTlRO9W1F9fgfjpk9 qoOf/I6JzQnTzROTIOnNmnMuWXhMosw= Date: Thu, 28 Aug 2025 13:05:55 +0100 MIME-Version: 1.0 Subject: Re: [PATCH] net: ethernet: ti: Prevent divide-by-zero in cpts_calc_mult_shift() To: Miaoqian Lin , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Matthias Brugger , AngeloGioacchino Del Regno , Thomas Gleixner , Grygorii Strashko , 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> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Vadim Fedorenko In-Reply-To: <20250828092224.46761-1-linmq006@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250828_050609_007434_B4BD913A X-CRM114-Status: UNSURE ( 7.30 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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...