From nobody Fri Sep 25 11:59:57 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 CEDFC3C9EF3; Sun, 13 Sep 2026 06:49:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789282147; cv=none; b=qXxnScZUl8pZJ9IV73vMGGPsxrTPRFe4VO8u3QzEQwXa4R9HTUOYTdes6N5Fb02aOPLOlfA5YKHZROKCoKaLngYZfcObwhn+WdeLYiwd6CYYvWGDI2wYNP2AhUAruTD8kpF0tdH2sYXuJDyhFwPAGbFjxJBKQcQuCXxTwFu4PrQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789282147; c=relaxed/simple; bh=LhYpJ485ik2w81eWufq8H1TOWNuj5hgG26G3w9ZImN0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=IAv2p5DeMTkD7hI3CYtFZnkPvqh4SC0xCHNz7MfyPTIyvpsdsRs9UnzqBhqs3uaGgZzospqthZ0fFCwjqHwGpICsGqPjoA2s+aZLnWU662KLfAfobqXrZ/3sJX0G3BYaLeBdmwR2UtVDtOWm0JRZX4LAP1nNahuypGXFBl0YULA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BK3kBiin; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BK3kBiin" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 48BC01F00898; Sun, 13 Sep 2026 06:49:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789282145; bh=XKqnaSQmKuSO22y7wuizhyR47ub2Nz2pDtirMarQmXk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BK3kBiinbza54tXVCGMTi/ymbCbFXEU04osBef/03viMesZ+PPQiAQ7l7FnSLkJmk RrJEp3IQoHBR1hNO8wgiEf8AfGEF0uEMKGJIT3YpsRB4xyYJMkpLvE1HoDa61mhpZp CX1APxHKbUox4RBNj+o+0yK9u+Ib4EVBqEYRw3TOaAV1kJxOy/QyJKQZafLXknr56t yikfx1RT6iXqt7sN9172Z2EkY982D0JoIZtYLFE+DZAXaDaTPgoZr5pEMvj6yH4EF0 3o6QpahtKkCmTMppOLE/dzaQuBILTWF6brBVKFhB9eFy5n9uEWZZqcXioc0fTFkEjh EGSc17Z13eEfA== From: Tzung-Bi Shih To: Wim Van Sebroeck , Guenter Roeck Cc: Baruch Siach , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, tzungbi@kernel.org Subject: [PATCH 1/3] watchdog: digicolor: Avoid division by zero Date: Sun, 13 Sep 2026 14:48:49 +0800 Message-ID: <20260913064851.8239-2-tzungbi@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260913064851.8239-1-tzungbi@kernel.org> References: <20260913064851.8239-1-tzungbi@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" clk_get_rate() could return 0. Avoid a division by zero panic. Since get_timeleft() cannot propagate errors, check the clock rate early in probe() and cache the rate in the driver data as it is unlikely to change at runtime. Fixes: 336694a01dae ("watchdog: digicolor: driver for Conexant Digicolor CX= 92755 SoC") Signed-off-by: Tzung-Bi Shih Acked-by: Baruch Siach --- drivers/watchdog/digicolor_wdt.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/watchdog/digicolor_wdt.c b/drivers/watchdog/digicolor_= wdt.c index 073d37867f47..de1a3267a972 100644 --- a/drivers/watchdog/digicolor_wdt.c +++ b/drivers/watchdog/digicolor_wdt.c @@ -25,6 +25,7 @@ struct dc_wdt { void __iomem *base; struct clk *clk; spinlock_t lock; + unsigned long rate; }; =20 static unsigned timeout; @@ -61,7 +62,7 @@ static int dc_wdt_start(struct watchdog_device *wdog) { struct dc_wdt *wdt =3D watchdog_get_drvdata(wdog); =20 - dc_wdt_set(wdt, wdog->timeout * clk_get_rate(wdt->clk)); + dc_wdt_set(wdt, wdog->timeout * wdt->rate); =20 return 0; } @@ -79,7 +80,7 @@ static int dc_wdt_set_timeout(struct watchdog_device *wdo= g, unsigned int t) { struct dc_wdt *wdt =3D watchdog_get_drvdata(wdog); =20 - dc_wdt_set(wdt, t * clk_get_rate(wdt->clk)); + dc_wdt_set(wdt, t * wdt->rate); wdog->timeout =3D t; =20 return 0; @@ -90,7 +91,7 @@ static unsigned int dc_wdt_get_timeleft(struct watchdog_d= evice *wdog) struct dc_wdt *wdt =3D watchdog_get_drvdata(wdog); uint32_t count =3D readl_relaxed(wdt->base + TIMER_A_COUNT); =20 - return count / clk_get_rate(wdt->clk); + return count / wdt->rate; } =20 static const struct watchdog_ops dc_wdt_ops =3D { @@ -130,7 +131,11 @@ static int dc_wdt_probe(struct platform_device *pdev) wdt->clk =3D devm_clk_get(dev, NULL); if (IS_ERR(wdt->clk)) return PTR_ERR(wdt->clk); - dc_wdt_wdd.max_timeout =3D U32_MAX / clk_get_rate(wdt->clk); + + wdt->rate =3D clk_get_rate(wdt->clk); + if (!wdt->rate) + return -EINVAL; + dc_wdt_wdd.max_timeout =3D U32_MAX / wdt->rate; dc_wdt_wdd.timeout =3D dc_wdt_wdd.max_timeout; dc_wdt_wdd.parent =3D dev; =20 --=20 2.53.0 From nobody Fri Sep 25 11:59:57 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 6857C3CB560; Sun, 13 Sep 2026 06:49:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789282149; cv=none; b=FHxZo+lbE/6XXSs4VHaUcmU8Yd6VimSev4bQ04N68krP3004M8Vuqj29maT/Qg2rSOVHFmPpMbrqQ3PUK4qLOXRffhDuod1j93uz8u6/bU+/zlpEBTnmSdsdNG0+Jw7L0EItBXCgNoJnbZrYQR/l+FjTCKOel60ilbbUsv3LdtA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789282149; c=relaxed/simple; bh=r3jcwyTedaTxb9b3RfNhohViDgy9af5oaw4AG343a7k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=nFC+KJbMrXfrpN3xaaAz9o/yL1MpntCwq8xcSPhf1roeWOBlvk9W3qJF8OrzFCyvKlsSvCdn9fWaRoMiweNFV1Kbvp8vQbcaHrWlkt8UAKPIwdKtgHnmmKB3KWLapuV6mJSlxLsipSY+bOvE1GkZoB/1P+ojnhkcaJmbsxF+lAs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=DDyNRJAS; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="DDyNRJAS" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D36801F000FF; Sun, 13 Sep 2026 06:49:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789282147; bh=GR8e9OThUzczma4Aaeh5prTyfxSVnwc9ScJ2htIrV/8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=DDyNRJASTISkX1Dy52ifusp1KPyPNlpx3aqX37nwH6hiRkY9AWq6aOkLTdOfxbVWE 10bm+s18xrfWpmJYiX2/A6Vxi915K5YgxQeKrxR/0Wr89F12rhz/Xl588IsnohGuX6 +WKabKsqw4zSbBhhS7q5x2Hx4OvzKFux31eD422T7G0u2VGKrakLrq7DeYQ+37UvJO 8klPhhKdMhW4dpc0sssjr4ruTcJxg50ckRrPfQLrbvpAy3EolAE0aA97Bcu67Gt/g0 6IukYsoPM3V85ghU5xTIDj+i0pb8Sinm2n53WRRQfI3nvw1wWvyUKCztsxRhwdzVHE qNfaePycyACtg== From: Tzung-Bi Shih To: Wim Van Sebroeck , Guenter Roeck Cc: Baruch Siach , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, tzungbi@kernel.org Subject: [PATCH 2/3] watchdog: rtd119x: Avoid division by zero Date: Sun, 13 Sep 2026 14:48:50 +0800 Message-ID: <20260913064851.8239-3-tzungbi@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260913064851.8239-1-tzungbi@kernel.org> References: <20260913064851.8239-1-tzungbi@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" clk_get_rate() could return 0. Avoid a division by zero panic. Fixes: 2bdf6acbfead ("watchdog: Add Realtek RTD1295") Signed-off-by: Tzung-Bi Shih --- drivers/watchdog/rtd119x_wdt.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/rtd119x_wdt.c b/drivers/watchdog/rtd119x_wdt.c index 984905695dde..0bfadb58917b 100644 --- a/drivers/watchdog/rtd119x_wdt.c +++ b/drivers/watchdog/rtd119x_wdt.c @@ -98,6 +98,7 @@ static int rtd119x_wdt_probe(struct platform_device *pdev) { struct device *dev =3D &pdev->dev; struct rtd119x_watchdog_device *data; + unsigned long rate; =20 data =3D devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) @@ -111,10 +112,14 @@ static int rtd119x_wdt_probe(struct platform_device *= pdev) if (IS_ERR(data->clk)) return PTR_ERR(data->clk); =20 + rate =3D clk_get_rate(data->clk); + if (!rate) + return -EINVAL; + data->wdt_dev.info =3D &rtd119x_wdt_info; data->wdt_dev.ops =3D &rtd119x_wdt_ops; data->wdt_dev.timeout =3D 120; - data->wdt_dev.max_timeout =3D 0xffffffff / clk_get_rate(data->clk); + data->wdt_dev.max_timeout =3D 0xffffffff / rate; data->wdt_dev.min_timeout =3D 1; data->wdt_dev.parent =3D dev; =20 --=20 2.53.0 From nobody Fri Sep 25 11:59:57 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 34DEA3CAE7F; Sun, 13 Sep 2026 06:49:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789282150; cv=none; b=sAgujC/qHE55bJKd/gKs6itgDnuvvh6Jt1oHfITx9Q6PniEy/DvwTV8423OPfwvjfyMhCGyImNLcT9PkLmQp0rBWSRKYqYFZ3C50Lc0y4/3y/PGDtbZKIxYgF+YAuFCMf2J7im5MYTyLmuHUMtdqT+fGLiOCJHKIegcWOAQKSvA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789282150; c=relaxed/simple; bh=pa9bi2gTpvDqDAwkZftMhy3DJPdhjXbXtM/QyyiPXq8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=eg/zZu6fn8yxakDFpRozEu15/zr+Pc7n13hbWEU/DnDTcGSozvv9owgs6OArKpyDuiGSxYWfh74P5HNUhRVgHH7UgLKv5c5X7k3qhN36vTjvw8x6z3jq/Rnql1Nf8KVuBi8HYMjxJLkBO+s5H0mjrfpTfWWCmxMJt1ZUPKyAE4c= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=S6CBRuU8; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="S6CBRuU8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 668401F00893; Sun, 13 Sep 2026 06:49:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789282148; bh=RH7auDzRZm51pq9Ic6ls/26JXCqmBMKMAK5aSQaL8cM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=S6CBRuU8fsWJxZyFpdXf0wfRSrKuLpDjGZcDV1dnIryvvH4sAdlJkyeV7RxjSxQzD /vtiVpkwFmblTvKBN5UzFdaY0xTBNkzfnreTTev1lEnJ2CS93ns3S95Hi3snMfPJXm ZhUNvFTVTXrd1/HpFLchKpYcQ7y5lRy4uJd9PIp1DQsohY/CHA45UrrOg10zDzBC57 r0S7nzAjxiJlfBtEoRV8WOMsQMZUajBTXBIG7pfZccMI1Uqwg2xKAjYD8xKDrExA0V iiIUsJz+M0Eu6YGYRWEZt/O1kscRLwp81QYP/LUvTsqUUtWEEHoynEXFNbhjl+WV+e uAjkkvwyd74bg== From: Tzung-Bi Shih To: Wim Van Sebroeck , Guenter Roeck Cc: Baruch Siach , linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org, tzungbi@kernel.org Subject: [PATCH 3/3] watchdog: rzv2h: Avoid division by zero Date: Sun, 13 Sep 2026 14:48:51 +0800 Message-ID: <20260913064851.8239-4-tzungbi@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260913064851.8239-1-tzungbi@kernel.org> References: <20260913064851.8239-1-tzungbi@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" clk_get_rate() could return 0. Avoid a division by zero panic. Fixes: f6febd0a30b6 ("watchdog: Add Watchdog Timer driver for RZ/V2H(P)") Signed-off-by: Tzung-Bi Shih --- drivers/watchdog/rzv2h_wdt.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/watchdog/rzv2h_wdt.c b/drivers/watchdog/rzv2h_wdt.c index 3b6abb66a1da..83540dd9a37b 100644 --- a/drivers/watchdog/rzv2h_wdt.c +++ b/drivers/watchdog/rzv2h_wdt.c @@ -278,6 +278,7 @@ static int rzv2h_wdt_probe(struct platform_device *pdev) struct device *dev =3D &pdev->dev; struct rzv2h_wdt_priv *priv; struct clk *count_clk; + unsigned long rate; int ret; =20 priv =3D devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); @@ -314,8 +315,12 @@ static int rzv2h_wdt_probe(struct platform_device *pde= v) return dev_err_probe(dev, -EINVAL, "Invalid count source\n"); } =20 + rate =3D clk_get_rate(count_clk); + if (!rate) + return dev_err_probe(dev, -EINVAL, "Invalid clock rate\n"); + priv->wdev.max_hw_heartbeat_ms =3D (MILLI * priv->of_data->timeout_cycles= * - priv->of_data->cks_div) / clk_get_rate(count_clk); + priv->of_data->cks_div) / rate; dev_dbg(dev, "max hw timeout of %dms\n", priv->wdev.max_hw_heartbeat_ms); =20 ret =3D devm_pm_runtime_enable(dev); --=20 2.53.0