From nobody Tue Nov 26 06:56:11 2024 Received: from mail-wm1-f49.google.com (mail-wm1-f49.google.com [209.85.128.49]) (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 890311EB9FC; Mon, 21 Oct 2024 12:56:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.49 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729515389; cv=none; b=tShUNNuJhjJr+1SBm4jFy9Hq3vwP7J0wfvsUFEICJLFrEa+QK965Q34ddkfXe/ZCzrrIiT5C291jo8d662uuhYi5Lfy7rT75JJf9pQeV/C72rxa+z3GnuWxiHYTANyfSb98fkmKdJy/3gAI/cSDDZdNAjM+rExD9jJ5oCXWkn5o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729515389; c=relaxed/simple; bh=0ClYzGYWuo9R4ytQT8+YomjzZyyvK/shpte3TSu50RA=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=M6XclNvg3mzALkx8dc152QSrnmdm0byEevaQOvaSMe+pmmYLHQcx4EQYjhgW+vRQfmlXJNH4WyYBCnJ5r+c5zCwW7p/Dvb5FwXx40E8hm9sA5hPPBtW55gf2JVa9Cy/yELpgHs6tgDGLS2dwRETtrJ+SxHisJ4adSADZfJB2RSY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=WmzM8OMK; arc=none smtp.client-ip=209.85.128.49 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="WmzM8OMK" Received: by mail-wm1-f49.google.com with SMTP id 5b1f17b1804b1-4314fa33a35so45598175e9.1; Mon, 21 Oct 2024 05:56:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1729515386; x=1730120186; 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=M4DbDXoWuKEPG/SkjaxUaXOQ8tk/bgeFy/xVB16h3Gg=; b=WmzM8OMKa4chw4UtNMIkyqRM6W+MxkBbMEre5NVw6cFckW2SfuoFH2P4nw5EuFdKFQ 4jnFjKXZx4ZCVAt7ZAx3waKavoJ1w8ZFXJ9ChGWAL1fjVI4VLwUtIpmYfHtqFhtV41MS S+crv52UN5BD10hvzFGOVqyFqwf9I+BrkvhevuhuSIM/SZPDYZ9IBA+GsSYOPiLWYK8U jzD6ZCobqfv2/MdgL6gT0rPlYOLyR26gESLtdOgA49Wd9SoC7BHG6y9r7XC4Ht3gNBA9 8wptuKzNw1V3259E0PZPM1QJxKoU4tdhbSS4BlfQlLUq7r8cBCaxxqbo0D0cS3uij6Fd X3mg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1729515386; x=1730120186; 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=M4DbDXoWuKEPG/SkjaxUaXOQ8tk/bgeFy/xVB16h3Gg=; b=HlEVEXK4dHXCok8PQburPUJSM2Q0nahtKc9SYjwkUB8TZxNJ9sKvdKzoMURqCY/gcH RBylTQMecXSNJ9AcyYq+UeZokDjVWiUbpYXNMG8yvLYaOjV8WjeTqPkneHhBo+/6SAVy o1ugrC6+ec7mOGKCT/9Dtah5akgy+44s063y4AOxVEP5mbulZk+i+6yJiwJaAiIFh7Ug Dh/+p1XBJnKnjWHal48/x9MDKIE7H00X3KgkBgrEaiOrRa+VfsMarM70uviEqoPBFMhE Ppo8fxNExbxkPkQePmMkVKv8T8J8sX6PtuNvHRVIWJ7eHuKbT1D2fSFm0iVm9FxuULXj 0w2g== X-Forwarded-Encrypted: i=1; AJvYcCVR1ai9mNHq6vwcAPWtBxTi74b8IoyxzDezrjJfGVraxfLJ61BqLSrh2oTolt3DXsXoTmuahZlwMJdnWiU=@vger.kernel.org, AJvYcCW2hT+EGuYCLdwFelExaidHMAZwaaDhwnU320GeoRMHGMoj+hv8rd/OQx7RkeJo3wn8pbdgTiZ58K0=@vger.kernel.org, AJvYcCWzmza8AXjDsGxSI90z9hRBRS8Nb9DZTZDwIeefX3LC84/jF1UnMM3U2LKI32B6FQCcf8CIdubLzOYilg==@vger.kernel.org X-Gm-Message-State: AOJu0YzPx29M6813NAXlhbbg4nr+Cf1BYzXRzo0k3nqs9kwwiUC6rma3 lWQzWB5J0YwXNlxSxHDSy5q2aEptI3+7UD190drYqpgxJOgABO3h X-Google-Smtp-Source: AGHT+IGZ8MiqwunkQyNVTGOJ9VHraenoSHSD98vz/0FpWLI2bapcbutIDFCTUd2ygH4Rgow6TNUO/w== X-Received: by 2002:a05:6000:1f0a:b0:374:c8e5:d568 with SMTP id ffacd0b85a97d-37eab6ee8abmr6798456f8f.29.1729515385527; Mon, 21 Oct 2024 05:56:25 -0700 (PDT) Received: from localhost (host-82-56-18-47.retail.telecomitalia.it. [82.56.18.47]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4316f570dd5sm57210805e9.3.2024.10.21.05.56.24 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Oct 2024 05:56:25 -0700 (PDT) From: Matteo Martelli Date: Mon, 21 Oct 2024 14:54:14 +0200 Subject: [PATCH v5 1/5] iio: core: add read_avail_release_resource callback to fix race 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: quoted-printable Message-Id: <20241021-iio-read-avail-release-v5-1-b168713fab33@gmail.com> References: <20241021-iio-read-avail-release-v5-0-b168713fab33@gmail.com> In-Reply-To: <20241021-iio-read-avail-release-v5-0-b168713fab33@gmail.com> To: Jonathan Cameron , Lars-Peter Clausen , Michael Hennerich , Alisa-Dariana Roman , Christian Eggers , Peter Rosin , Paul Cercueil , Sebastian Reichel Cc: linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-pm@vger.kernel.org, Matteo Martelli X-Mailer: b4 0.14.2 Some iio drivers currently share an available info buffer that might be changed while iio core prints it to sysfs. To avoid the buffer corruption, add a release callback to let iio drivers allocate a copy of the available info buffer and later free it in the release callback. Such control is kept in the driver logic so that some driver that needs a big available info buffer might also perform some check to keep the copied buffer around in case no race has occurred. Signed-off-by: Matteo Martelli --- drivers/iio/industrialio-core.c | 14 +++++++++++--- include/linux/iio/iio.h | 4 ++++ 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-cor= e.c index 6a6568d4a2cb3a3f63381d5a6f25a2881b3ba2ed..4aea9de9f15a4d70f9d02fb3d47= df49eef8c8423 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -859,12 +859,20 @@ static ssize_t iio_read_channel_info_avail(struct dev= ice *dev, return ret; switch (ret) { case IIO_AVAIL_LIST: - return iio_format_avail_list(buf, vals, type, length); + ret =3D iio_format_avail_list(buf, vals, type, length); + break; case IIO_AVAIL_RANGE: - return iio_format_avail_range(buf, vals, type); + ret =3D iio_format_avail_range(buf, vals, type); + break; default: - return -EINVAL; + ret =3D -EINVAL; } + + if (indio_dev->info->read_avail_release_resource) + indio_dev->info->read_avail_release_resource( + indio_dev, this_attr->c, vals, this_attr->address); + + return ret; } =20 /** diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 3a9b57187a958d6e65c699cf7814df5bac9a99e3..03bb765670a0c5f0129fc677c3a= 4a4cb38f4dad1 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -491,6 +491,10 @@ struct iio_info { int *length, long mask); =20 + void (*read_avail_release_resource)(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + const int *vals, long mask); + int (*write_raw)(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, --=20 2.47.0