From patchwork Tue Jan 30 12:48:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bartosz Golaszewski X-Patchwork-Id: 768653 Received: from mail-wr1-f47.google.com (mail-wr1-f47.google.com [209.85.221.47]) (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 6E4921292F9 for ; Tue, 30 Jan 2024 12:49:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.47 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706618943; cv=none; b=lHONxfBwWPgw+fh4sIgxpQ7368yMH+cj8RwyD2ScPQUhlrpX0Rr934C4vP7CT6GkInyaIwq9FeVHDFO0oQ5WoaRAVBH8rSg2kFwhHzaOl/R1jijtnDiuy7bc2IPAU8+lr8b1eGujIMLkl2k+e659/78e4j0F38Q4WP7JkxYrVVs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706618943; c=relaxed/simple; bh=p9qFxfRDRuKahCeEITtAp/nZTu9vev5Cmk1NVuQ7PFc=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=DYMrMIMUoevIFlVEoCczaEmBu3WGmnYDINbA67P+/seLeIdpxuOxvo32ZLk70g0xISSV7s0n8w1qkomCBQs+7grJXb80xIBybYGV4gbjJB/VjDQxR0JLMV893QTcAV8dlcDcZy3ZFzmOBpMuYX+SdEh1qUkyOZpT8zwN5sYvy98= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=bgdev.pl; spf=none smtp.mailfrom=bgdev.pl; dkim=pass (2048-bit key) header.d=bgdev-pl.20230601.gappssmtp.com header.i=@bgdev-pl.20230601.gappssmtp.com header.b=DUZqnO4K; arc=none smtp.client-ip=209.85.221.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=bgdev.pl Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bgdev.pl Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bgdev-pl.20230601.gappssmtp.com header.i=@bgdev-pl.20230601.gappssmtp.com header.b="DUZqnO4K" Received: by mail-wr1-f47.google.com with SMTP id ffacd0b85a97d-33ae7ae1c32so1714656f8f.3 for ; Tue, 30 Jan 2024 04:49:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20230601.gappssmtp.com; s=20230601; t=1706618940; x=1707223740; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=3mlp9NoRNWG5wkw0gnE37vvJcfWnX6lVcfqfuQVzAw4=; b=DUZqnO4KCNJgb4pBBA8CSjJuCPOyuE5s5ZjBXIF8c9XkSAI+3UYiRx+9uW8F4jNf6v 6SwOc8D2sxT4Gd6tYe6aahVcH7qt0vNZwdHZX+hdwJG/BLPX4yAzLSyKmwhhSmX+oSve KWD1TDGzEJCcu1Zg64tiytwBXoVOCF6w0QonbyBkiTKOmEW3CQJT0wxIIwBhKNwoy4yb TsjFmBn5rch2ha6S9FDlspKMx+OP80LQ98PIYMQvtNeKK3ug4Wb+/eGPeGWcrhwCgwzk nIGNMMXUTk0ML20ZXWlqpvLpJyTPitbof+A7sfSHijHFF3J41o/B12Pu1ETEPz8uG+0a ozJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1706618940; x=1707223740; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=3mlp9NoRNWG5wkw0gnE37vvJcfWnX6lVcfqfuQVzAw4=; b=gfqvDUUGTxXMrwX8DCSga3kB+zt+RYn8K+D1uqAmvJHVHqlHWFhE3w7yTGiDaPcizl yCtMTJnd9o5Jut20HZyyBGckYU0cacMVS2MalVxTgnm8LrAyUWpgfjSU2YWKYP8rUkKi RtoHI+QV/gB5yeuPp5+iHaFVuucXghSY5wVB9LyW8gZW9i7xdDX5OuUIo5xgv9xdkqA9 hzuiD3phqmXBcPolg3zsOPIPOs7Y32doJn2Wm5406H1Cb9tUNjoT75eGjdEt6R4K8t4/ 2sxs0A9t9XR3swRb6pSYR4AlsT+1TJHQKE4GxGFnAqWUE1VpH4A7HUG2NnsySSDJMztH +4gQ== X-Gm-Message-State: AOJu0YySnCmOBm4kn52qd9bPJoOo2lK+aRagI9sevGpG3TKv8vV4FZiw 58WCc5Nit/aZNOpoGP2DBpfgoiMgiejT/yPsmaZ6IOSS+5h7HPI/dId6yYPIekE= X-Google-Smtp-Source: AGHT+IGDWA2iBJpdCn+igJe5tAk5amog3d34nSIBkescrm60Rf5It6dm8S+wfa5Hoowj22tI2nU+Ng== X-Received: by 2002:a5d:588b:0:b0:33a:f4d6:613 with SMTP id n11-20020a5d588b000000b0033af4d60613mr3528661wrf.69.1706618939847; Tue, 30 Jan 2024 04:48:59 -0800 (PST) Received: from brgl-uxlite.home ([2a01:cb1d:334:ac00:abc8:f77e:abeb:129c]) by smtp.gmail.com with ESMTPSA id en8-20020a056000420800b0033940016d6esm6625337wrb.93.2024.01.30.04.48.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 30 Jan 2024 04:48:59 -0800 (PST) From: Bartosz Golaszewski To: Linus Walleij , Kent Gibson , Alex Elder , Geert Uytterhoeven , "Paul E . McKenney" , Andy Shevchenko , Wolfram Sang Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Bartosz Golaszewski Subject: [PATCH 22/22] gpio: mark unsafe gpio_chip manipulators as deprecated Date: Tue, 30 Jan 2024 13:48:28 +0100 Message-Id: <20240130124828.14678-23-brgl@bgdev.pl> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20240130124828.14678-1-brgl@bgdev.pl> References: <20240130124828.14678-1-brgl@bgdev.pl> Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Bartosz Golaszewski We still have some functions that return the address of the GPIO chip associated with the GPIO device. This is dangerous and the users should find a better solution. Let's add appropriate comments to the kernel docs. Signed-off-by: Bartosz Golaszewski Reviewed-by: Linus Walleij --- drivers/gpio/gpiolib.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 5741bbfdc178..7ecdd8cc39c5 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -211,6 +211,11 @@ EXPORT_SYMBOL_GPL(desc_to_gpio); /** * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs * @desc: descriptor to return the chip of + * + * *DEPRECATED* + * This function is unsafe and should not be used. Using the chip address + * without taking the SRCU read lock may result in dereferencing a dangling + * pointer. */ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) { @@ -275,6 +280,7 @@ EXPORT_SYMBOL(gpio_device_get_label); * Returns: * Address of the GPIO chip backing this device. * + * *DEPRECATED* * Until we can get rid of all non-driver users of struct gpio_chip, we must * provide a way of retrieving the pointer to it from struct gpio_device. This * is *NOT* safe as the GPIO API is considered to be hot-unpluggable and the