From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-183.mta1.migadu.com (out-183.mta1.migadu.com [95.215.58.183]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3A0F91FECDF for ; Tue, 27 May 2025 09:52:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.183 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748339558; cv=none; b=LaeSfMo0q3dEy93sORxd6eCoe+sldCzUtNsOF4NCis3FggphRt7xA4npEZ8N4Ufko+hnbm3jMQ940YyYIcS0k8XjiJ7L32K0SM0qpbd/011v602+w5WVTEHik/5vi6aCpdYuvhxaqSKJzgwm7FYKgp5epoxHq+6So/SpICejn04= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748339558; c=relaxed/simple; bh=ySN5SL2V08gK0RzuM9krJbs2V0mmKi5sIxxDx4Ebdeo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=fnfKFfsiqI5VS7IiVa7ill8SdlEJ5y2tYKFm0ofMIGhZQxild9jSgbNrJekDjfgQRplgqUvopmlSRYemfgy1YPZ7zZfMsm14+61FkgwrUkbbSlAd8twxXdBbV0XZFylm7YBW63JM4DUH1AKoLAmD72NItVAxn56/2yABtoniJqk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=PG14+0f5; arc=none smtp.client-ip=95.215.58.183 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="PG14+0f5" Message-ID: <6147503e-1e73-42dc-a2b9-1b0cf26ca147@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1748339554; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zNzPqOcrIMLkbW6pqRkowgAwEnkW9pgS1P80rwoJM3g=; b=PG14+0f5KR1BMnGZAy6/w+as+/MDDALfjtqd2pISAmd/GyJsxozPgbxkP36Ulhp0xRYSQV HWL9XZg1J5r+JF4BVayfI9XukkXMpYtBoeYASJgpNuhHawLQJSIQ6WOHZbpRvChvCLljeh hy28I9XIT+OxVgBZb66LRh7ViM+zpyw= Date: Tue, 27 May 2025 17:52:26 +0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] net: stmmac: add explicit check and error on invalid PTP clock rate To: =?UTF-8?Q?Alexis_Lothor=C3=A9?= , Alexandre Torgue , Jose Abreu , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Richard Cochran Cc: Thomas Petazzoni , Maxime Chevallier , netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20250523-stmmac_tstamp_div-v1-1-bca8a5a3a477@bootlin.com> <8f1928e5-472e-4140-875c-6b5743be8fd3@linux.dev> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Yanteng Si In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 5/26/25 10:42 PM, Alexis Lothoré 写道: > On Mon May 26, 2025 at 4:22 AM CEST, Yanteng Si wrote: >> 在 5/23/25 7:46 PM, Alexis Lothoré 写道: >>> While some platforms implementing dwmac open-code the clk_ptp_rate >>> value, some others dynamically retrieve the value at runtime. If the >>> retrieved value happens to be 0 for any reason, it will eventually >>> propagate up to PTP initialization when bringing up the interface, >>> leading to a divide by 0: > [...] > >> From your description, I cannot determine the scope >> of "some platforms". My point is: if there are only >> a few platforms, can we find a way to handle this in >> the directory of the corresponding platform? > From what I can see, it can affect any platform using the stmmac driver as > the platform driver (except maybe dwmac-qcom-ethqos.c, which enforces an > open-coded clk_ptp_rate after the stmmac_probe_config_dt call that sets > the clk_ptp_rate), if the platform declares a dedicated clk_ptp_ref clock. > So I would rather say that it can affect most of the platforms. > > In my case, I have observed the issue with the dwmac-stm32.c driver, on an > STM32MP157a-dk1 platform. Okay! > >> And there need a Fixes tag. > Ok, I'll add a relevant Fixes tag. On this premise, Reviewed-by: Yanteng Si Thanks, Yanteng > > Alexis > >>> Signed-off-by: Alexis Lothoré >>> --- >>> drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 +++++ >>> 1 file changed, 5 insertions(+) >>> >>> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c >>> index 918d7f2e8ba992208d7d6521a1e9dba01086058f..f68e3ece919cc88d0bf199a394bc7e44b5dee095 100644 >>> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c >>> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c >>> @@ -835,6 +835,11 @@ int stmmac_init_tstamp_counter(struct stmmac_priv *priv, u32 systime_flags) >>> if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp)) >>> return -EOPNOTSUPP; >>> >>> + if (!priv->plat->clk_ptp_rate) { >>> + netdev_err(priv->dev, "Invalid PTP clock rate"); >>> + return -EINVAL; >>> + } >>> + >>> stmmac_config_hw_tstamping(priv, priv->ptpaddr, systime_flags); >>> priv->systime_flags = systime_flags; >>> >>> >>> --- >>> base-commit: e0e2f78243385e7188a57fcfceb6a19f723f1dff >>> change-id: 20250522-stmmac_tstamp_div-f55112f06029 >>> >>> Best regards, > > >