From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [217.70.183.194]) (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 3EBED2690D0; Wed, 28 May 2025 08:30:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.194 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748421010; cv=none; b=mS8/UEFJvaNS7n2w3jq25YkqBpADEnOzwZJULDrxKZr4HXRV2ovz+35M3kt5+Uc8Lck2YOS20+jUfCyjuySNStSIcMwDoJqpqNh/CzaBu9EyKCzmG6+rFqfuoLsqJhGfzC6Kmj0nckUbGxSQv1sDtksZeeQ8q3Ox/fYz8DXUX9g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748421010; c=relaxed/simple; bh=zVMhBykYafqvfCGtnRDyOCKWQDF3UHJ/6B0XGwg+nsU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=CQ0hP8uqTYlqmDx4RxM16cdWxRmxmnOVZK1yqWpd+3Z+Dr/osIEkJIputkbvDJMIbn1/cXzmxb9T4Wr0l5lGpLjbsoWF2cnWKFN++mriFKH8pMNJ40a2Hoj0BzmuPR46pTOCeKPPsjmrbqtPSgcSymJN0QrtDb93egLzmhtqRvE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=Ef1iKOEY; arc=none smtp.client-ip=217.70.183.194 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="Ef1iKOEY" Received: by mail.gandi.net (Postfix) with ESMTPSA id 86C6943195; Wed, 28 May 2025 08:29:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1748421000; 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=q0z9ri+70Fs+CgFUVGQkY1TOdR2du9mAIdijZA8JTVA=; b=Ef1iKOEYnzY+LmVqROaqkhZPQomDgmIowgIPw82gpaCY/dCccNE+xH9pwLHs0ScQCJLwiv G2HYScMCC5qvK2A9VIeHPOIAv9eGrARc62IXWDQ9rd4qojVFvXUfshOHr8iGMsf+PMANVK xiPs5yb1yJCvv2U6Cwo12U4hQXYFbhHMsz2p8lrvuvZI480YbycX14cH/DEuXG8Ty8AwiH y3NcFuc+i91abPFg6c75HRqGv+5cuqq04nVQC/3PNBK1/Xk9UitVYhUth7cZ9m6vC0BUUX AGowNvn5lhHy8MEXBh2SEosUYLKVPjYRxyks/+iVtcI2gs/RvJDYKkWOEcMUFw== From: =?utf-8?q?Alexis_Lothor=C3=A9?= Date: Wed, 28 May 2025 10:29:50 +0200 Subject: [PATCH v3 1/2] net: stmmac: make sure that ptp_rate is not 0 before configuring timestamping Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-Id: <20250528-stmmac_tstamp_div-v3-1-b525ecdfd84c@bootlin.com> References: <20250528-stmmac_tstamp_div-v3-0-b525ecdfd84c@bootlin.com> In-Reply-To: <20250528-stmmac_tstamp_div-v3-0-b525ecdfd84c@bootlin.com> To: Alexandre Torgue , Jose Abreu , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Richard Cochran , Phil Reid 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, Jose Abreu , =?utf-8?q?Alexis_Lothor=C3=A9?= X-Mailer: b4 0.14.2 X-GND-State: clean X-GND-Score: -100 X-GND-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtddtgddvvdejkeculddtuddrgeefvddrtddtmdcutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfitefpfffkpdcuggftfghnshhusghstghrihgsvgenuceurghilhhouhhtmecufedtudenucesvcftvggtihhpihgvnhhtshculddquddttddmnecujfgurhephfffufggtgfgkfhfjgfvvefosehtkeertdertdejnecuhfhrohhmpeetlhgvgihishcunfhothhhohhrrocuoegrlhgvgihishdrlhhothhhohhrvgessghoohhtlhhinhdrtghomheqnecuggftrfgrthhtvghrnhepgeevgefhteffuefhheekkeelffffvdeugffgveejffdtvdffudehtedtieevteetnecukfhppeeltddrkeelrdduieefrdduvdejnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehinhgvthepledtrdekledrudeifedruddvjedphhgvlhhopegludelvddrudeikedrtddrvddungdpmhgrihhlfhhrohhmpegrlhgvgihishdrlhhothhhohhrvgessghoohhtlhhinhdrtghomhdpnhgspghrtghpthhtohepudekpdhrtghpthhtohepthhhohhmrghsrdhpvghtrgiiiihonhhisegsohhothhlihhnrdgtohhmpdhrtghpthhtoheplhhinhhugidqrghrmhdqkhgvrhhnvghlsehlihhsthhsrdhinhhfrhgruggvrggurdhorhhgpdhrtghpthhtoheprghlvgigihhsrdhlohhthhhorhgvsegsohhothhlihhnrdgtohhmpdhrtghpthhtohepmhgtohhquhgvlhhin hdrshhtmhefvdesghhmrghilhdrtghomhdprhgtphhtthhopegrlhgvgigrnhgurhgvrdhtohhrghhuvgesfhhoshhsrdhsthdrtghomhdprhgtphhtthhopehlihhnuhigqdhsthhmfedvsehsthdqmhguqdhmrghilhhmrghnrdhsthhorhhmrhgvphhlhidrtghomhdprhgtphhtthhopehmrgigihhmvgdrtghhvghvrghllhhivghrsegsohhothhlihhnrdgtohhmpdhrtghpthhtohepuggrvhgvmhesuggrvhgvmhhlohhfthdrnhgvth X-GND-Sasl: alexis.lothore@bootlin.com The stmmac platform drivers that do not open-code the clk_ptp_rate value after having retrieved the default one from the device-tree can end up with 0 in clk_ptp_rate (as clk_get_rate can return 0). It will eventually propagate up to PTP initialization when bringing up the interface, leading to a divide by 0: Division by zero in kernel. CPU: 1 UID: 0 PID: 1 Comm: swapper/0 Not tainted 6.12.30-00001-g48313bd5768a #22 Hardware name: STM32 (Device Tree Support) Call trace: unwind_backtrace from show_stack+0x18/0x1c show_stack from dump_stack_lvl+0x6c/0x8c dump_stack_lvl from Ldiv0_64+0x8/0x18 Ldiv0_64 from stmmac_init_tstamp_counter+0x190/0x1a4 stmmac_init_tstamp_counter from stmmac_hw_setup+0xc1c/0x111c stmmac_hw_setup from __stmmac_open+0x18c/0x434 __stmmac_open from stmmac_open+0x3c/0xbc stmmac_open from __dev_open+0xf4/0x1ac __dev_open from __dev_change_flags+0x1cc/0x224 __dev_change_flags from dev_change_flags+0x24/0x60 dev_change_flags from ip_auto_config+0x2e8/0x11a0 ip_auto_config from do_one_initcall+0x84/0x33c do_one_initcall from kernel_init_freeable+0x1b8/0x214 kernel_init_freeable from kernel_init+0x24/0x140 kernel_init from ret_from_fork+0x14/0x28 Exception stack(0xe0815fb0 to 0xe0815ff8) Prevent this division by 0 by adding an explicit check and error log about the actual issue. While at it, remove the same check from stmmac_ptp_register, which then becomes duplicate Fixes: 19d857c9038e ("stmmac: Fix calculations for ptp counters when clock input = 50Mhz.") Signed-off-by: Alexis Lothoré --- Changes in v3: - remove now-duplicate check - reword commit message --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 5 +++++ drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) 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; diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c index a6b1de9a251dd4fdc083e59717b57ff3b94cefb4..5c85040a1b937ecd1deb701ceaca47df5f3834f3 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_ptp.c @@ -303,7 +303,7 @@ void stmmac_ptp_register(struct stmmac_priv *priv) /* Calculate the clock domain crossing (CDC) error if necessary */ priv->plat->cdc_error_adj = 0; - if (priv->plat->has_gmac4 && priv->plat->clk_ptp_rate) + if (priv->plat->has_gmac4) priv->plat->cdc_error_adj = (2 * NSEC_PER_SEC) / priv->plat->clk_ptp_rate; stmmac_ptp_clock_ops.n_per_out = priv->dma_cap.pps_out_num; -- 2.49.0