From patchwork Tue Jul 9 12:59:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krzysztof Kozlowski X-Patchwork-Id: 812245 Received: from mail-ed1-f50.google.com (mail-ed1-f50.google.com [209.85.208.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2C08715B552 for ; Tue, 9 Jul 2024 12:59:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.50 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720530000; cv=none; b=n4OnsRHtVG+YmgmekxxcbDgksmztSevNdRt3wL1BbF46VefDwGhmHIWZfpeMN0XK6vSaYJ3UU5cQ6kU0mX58ce2PBBmgWgSW8ZGasqosorI2Kt0NPbwWI9rLH2mQ9yAfp/79kOCRIEiRCX+EJwVBC61ODTds1mDoxKKJk+Ns9ho= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720530000; c=relaxed/simple; bh=iOmmg+031BO+zTgqj4Da5Rimz0tYxzcZBtos8xp+M6k=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=WWXX7hA9n2SH/wa8l72632ghXOSHeyhN85Y7IJp77qVlY6Vbi2EJEXB06JM7nl6FkJK+32eg9n+NsCFA8nUfzFU+rEWWZI2GsD81vl+as/NX6z3w68RCm+TXdCiCDixCKzEclhZwBp+sWBHzJCFzCegqW9BMgUIin/CDKpYqkpM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=r3p18c5+; arc=none smtp.client-ip=209.85.208.50 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="r3p18c5+" Received: by mail-ed1-f50.google.com with SMTP id 4fb4d7f45d1cf-58ef19aa6c4so5349693a12.2 for ; Tue, 09 Jul 2024 05:59:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1720529995; x=1721134795; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=Hpq15xCFbtYALDYFY4KDY3RIliIQDLzZlDT5dVHuf9o=; b=r3p18c5+wh7LfWBepgVgu2EyR5nasCnEG41JkyIj/nzLfBc5hXwJPb6oOv5Vnh4tMA zTOJu8NPoV0apuCbvClJgOSZIdz/yOQXg9R+Cnu0/6Y6CrGKiLB7OBzVr9bv3m1PUZF1 ejclrxDBfNcTLO4B/53B1sjR2WlgrAyJE8SIiCZLI5IYpbgwQ/ylLLGphyJyEp4Y4MEo tJCp6WG76IrNlN9HmdCJ9bOGeOiFyXotqXbYPvFp7ekmbo4EUNsxqSepPEqpV0pROAKH 9hHdWlDylFRK7ib62APSaAD/pTTG2GtumSBBqLQzUcv0jhnIznXA/9xyF48Dw9JaUNIh YdjA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1720529995; x=1721134795; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Hpq15xCFbtYALDYFY4KDY3RIliIQDLzZlDT5dVHuf9o=; b=DAligg1t7SfjKCFy7zNxqgAp/kZdIOrJA6xqLaS+G/X4nXulTCaHl9Qh4g+JgwI3iC fcMEMF8U4YqiB2AQxNzHl1DVJ/teuKNHhYX3axtmAUYC4/4F6ZYM6Q+Q3YpEeIXoKI25 ZFZnqAgzWS7Svq4qHJnPnQj8+T3WXGMn7CNgxQfLvWqrqu1l1orHRm7Qh9pCQu05eeuA 2Fw6YWg1b7hZES6qwgPNZO0/K1m8iuEtCpB8pPCfTTI7Rm9G/Z+ECyuMYII5LNKgDjVY v7AR7tPG4zXSDMIQOYoFxGKgVUWEZkI4+I+HLWirOw6UO0VrnsQm0DxJ6WHAWRGOnoei oCvQ== X-Forwarded-Encrypted: i=1; AJvYcCV8OA1C9eJskZ5FcFvnDPsweOF7EbOAO622B0K5zn1kKbg8SiwZWYQZZYP71ye2j8zzjCMyrVdDQzhCP8vdEUkiDyZ8uwPdXRFQEslF2NermUU= X-Gm-Message-State: AOJu0YyeufPMwApj8r9CDs18b58UEgdXxjLNDp192icd4iYaMcEZjAp7 i/3qW3Id4GdmqqZlX98Zp1h33OQI5OSc8jT9ao+LKYEiglXfMUDXNPAfe2EXu5sn9M5xuQ5RKAV N X-Google-Smtp-Source: AGHT+IEnBykQHOg72vb+3a+PwqhhC6nKKTeE5KfSm0UJxuh/0+T6xpvhz21MgJnNUb9TuX3+w8AJwQ== X-Received: by 2002:a05:6402:5256:b0:58d:eca:b9bf with SMTP id 4fb4d7f45d1cf-594bcab156emr1744682a12.37.1720529995591; Tue, 09 Jul 2024 05:59:55 -0700 (PDT) Received: from [127.0.1.1] ([178.197.219.137]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a780a6e157bsm76643166b.80.2024.07.09.05.59.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 09 Jul 2024 05:59:55 -0700 (PDT) From: Krzysztof Kozlowski Date: Tue, 09 Jul 2024 14:59:31 +0200 Subject: [PATCH 01/12] thermal/drivers/broadcom: fix race between removal and clock disable Precedence: bulk X-Mailing-List: linux-samsung-soc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240709-thermal-probe-v1-1-241644e2b6e0@linaro.org> References: <20240709-thermal-probe-v1-0-241644e2b6e0@linaro.org> In-Reply-To: <20240709-thermal-probe-v1-0-241644e2b6e0@linaro.org> To: "Rafael J. Wysocki" , Daniel Lezcano , Zhang Rui , Lukasz Luba , Florian Fainelli , Ray Jui , Scott Branden , Broadcom internal kernel review list , Bartlomiej Zolnierkiewicz , Krzysztof Kozlowski , Alim Akhtar , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Amit Kucheria , Thara Gopinath Cc: linux-pm@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org, imx@lists.linux.dev, linux-arm-msm@vger.kernel.org, stable@vger.kernel.org, Krzysztof Kozlowski X-Mailer: b4 0.14.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3012; i=krzysztof.kozlowski@linaro.org; h=from:subject:message-id; bh=iOmmg+031BO+zTgqj4Da5Rimz0tYxzcZBtos8xp+M6k=; b=owEBbQKS/ZANAwAKAcE3ZuaGi4PXAcsmYgBmjTQ83IPlStNA8YpS9fGSEe7VT+gKCvXpGdAfJ 5hWjtkURB6JAjMEAAEKAB0WIQTd0mIoPREbIztuuKjBN2bmhouD1wUCZo00PAAKCRDBN2bmhouD 117aEACEcxeLvNx+Ph7F3Sf3xCVkyz8ERxrRXQXccTRTOYxedP0TJzaaKHlqyz+OlCmtcu9wKpm WRjmQxWKqPDDFmWgr4Y04n4SFXB05HI6p/7z3w+Qythc9voHFnPIezcyDwyr0H0DR+jZ1HLki57 pixbSiu1Oh7tFR6L/Za/4zrtmS0BDmJqfKOyUciOuKmucNdB5o2lOEIG5pGuaTP95+3pVvbGYoO ECPivYLlIIgzh4JRpRQdSKVewxs5TqSOc7Fjq9LI/I9XylD0k3GwhSVwvYdKAPJ6fhQcCIyeagv uX+tI+vwiGKZIXEGskAnZfwjacFGXNFY8hQKwXSiBooGOi5Bmdqh7FwGlomD0+XPFzSqUkyLJ4u qqUQ13wRtzhsc7FhtAlIHw2yrME7IeTNrORvMj9NSD1BEixkbPEN6uc22OqcVS/+bF+PyFVIL4j NEJbL+MzL5fhn176g4N+LyG+L7fpLqJvjWwgHOOmOZk0CTwie+3BOocSd40x7giMK+RhpOJPiDQ v0SF1Cy6EIdDlduw+X5sl681DnxfiPWMg3FZ1Sy2OGhh7M0UKc20QG3ecnPvMZys7AmalVQY14E 8ywJEmETlZS04IXHms1rYHSYGBL2DP4tNxOGJNNE4Prn+GgvrOltn4hs5agcW27LEZSHJsj9d7N 8KUwp2YTb4FzNfQ== X-Developer-Key: i=krzysztof.kozlowski@linaro.org; a=openpgp; fpr=9BD07E0E0C51F8D59677B7541B93437D3B41629B During the probe, driver enables clocks necessary to access registers (in get_temp()) and then registers thermal zone with managed-resources (devm) interface. Removal of device is not done in reversed order, because: 1. Clock will be disabled in driver remove() callback - thermal zone is still registered and accessible to users, 2. devm interface will unregister thermal zone. This leaves short window between (1) and (2) for accessing the get_temp() callback with disabled clock. Fix this by enabling clock also via devm-interface, so entire cleanup path will be in proper, reversed order. Fixes: 8454c8c09c77 ("thermal/drivers/bcm2835: Remove buggy call to thermal_of_zone_unregister") Cc: Signed-off-by: Krzysztof Kozlowski --- drivers/thermal/broadcom/bcm2835_thermal.c | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) diff --git a/drivers/thermal/broadcom/bcm2835_thermal.c b/drivers/thermal/broadcom/bcm2835_thermal.c index 5c1cebe07580..3b1030fc4fbf 100644 --- a/drivers/thermal/broadcom/bcm2835_thermal.c +++ b/drivers/thermal/broadcom/bcm2835_thermal.c @@ -185,7 +185,7 @@ static int bcm2835_thermal_probe(struct platform_device *pdev) return err; } - data->clk = devm_clk_get(&pdev->dev, NULL); + data->clk = devm_clk_get_enabled(&pdev->dev, NULL); if (IS_ERR(data->clk)) { err = PTR_ERR(data->clk); if (err != -EPROBE_DEFER) @@ -193,10 +193,6 @@ static int bcm2835_thermal_probe(struct platform_device *pdev) return err; } - err = clk_prepare_enable(data->clk); - if (err) - return err; - rate = clk_get_rate(data->clk); if ((rate < 1920000) || (rate > 5000000)) dev_warn(&pdev->dev, @@ -211,7 +207,7 @@ static int bcm2835_thermal_probe(struct platform_device *pdev) dev_err(&pdev->dev, "Failed to register the thermal device: %d\n", err); - goto err_clk; + return err; } /* @@ -236,7 +232,7 @@ static int bcm2835_thermal_probe(struct platform_device *pdev) dev_err(&pdev->dev, "Not able to read trip_temp: %d\n", err); - goto err_tz; + return err; } /* set bandgap reference voltage and enable voltage regulator */ @@ -269,17 +265,11 @@ static int bcm2835_thermal_probe(struct platform_device *pdev) */ err = thermal_add_hwmon_sysfs(tz); if (err) - goto err_tz; + return err; bcm2835_thermal_debugfs(pdev); return 0; -err_tz: - devm_thermal_of_zone_unregister(&pdev->dev, tz); -err_clk: - clk_disable_unprepare(data->clk); - - return err; } static void bcm2835_thermal_remove(struct platform_device *pdev) @@ -287,7 +277,6 @@ static void bcm2835_thermal_remove(struct platform_device *pdev) struct bcm2835_thermal_data *data = platform_get_drvdata(pdev); debugfs_remove_recursive(data->debugfsdir); - clk_disable_unprepare(data->clk); } static struct platform_driver bcm2835_thermal_driver = {