From mboxrd@z Thu Jan 1 00:00:00 1970 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 6337C37107E for ; Mon, 1 Jun 2026 19:59:16 +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=1780343959; cv=none; b=IDts3+VbhVv9ePsBmcw4UX6B/kzeoC9h1rVZEwaCbYgkjdwfmU8sq+h6ElSVTCTQWBtekJI6MjNVO+ROonO0iTBoKb7CbXz0Mm2mr7lmZiyFbhlvOnLY0NUakmsDmN0aTca2mxfSig3asTsxy4jJoFM7hfeLl1lJe2MOzKDekgo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780343959; c=relaxed/simple; bh=xudYHSX3gEKvM8xeFlafswYKy/aJakOw1m5HANXf9zU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Fzbn+oFGRvaM5AldkWo7a7OCN/RxtTgAxN6etP9zn2ypV+IqcDKcEJIJyrhZTp6kczVvyQnLkW2BaVh5g2LGJt/9mcjwAw2c8Azya9UoLJ5cucSxrBwzv+z0Qd3cmzJSHDNqeGAtjwesmh/fmchSWfPVWhF4VxtythrRAhRuH/Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iTtS+BfG; 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="iTtS+BfG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 233D21F00893; Mon, 1 Jun 2026 19:59:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780343956; bh=SvBe1yOr2Uh/v5H92upKLAaXAKnWjtrsVXCG+QShwsI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=iTtS+BfGEebRcEDxwJ93XAT7qRHadGMWG060BpwxI9jWnBB4G3QhMBPrTyqy1m6u0 5Rf1iA0bX/6JOGu6LWMq6T4zBPUvgOw0pGdWc5CCRH+v1S4OElSOtjEEK4LBcRwCpi jFBCvaoBVnxO+ThaUQ/xJbWlcViTT5SxL0+orwc1KQJ1ZU3cgG9X4/AR1Bnp9zPySN ILLztHboUGJPePzRg/TMOix51+IVq+8izJNnYecnD4496daEnOQvl+9676TOPfyOqq Jl7r+IKToBOScAsmsOiODcX0mQkFBP+ZhI8FZ+9zErHidgRw1hI2VZJ733BNSgkUHU D684Ozh6aQjLQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Abdurrahman Hussain , Bartosz Golaszewski , Guenter Roeck , Sasha Levin Subject: [PATCH 6.12.y] hwmon: (pmbus/adm1266) serialize GPIO PMBus accesses with pmbus_lock Date: Mon, 1 Jun 2026 15:59:14 -0400 Message-ID: <20260601195914.1214650-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026052841-turbulent-emblaze-4f92@gregkh> References: <2026052841-turbulent-emblaze-4f92@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Abdurrahman Hussain [ Upstream commit bab8c6fb5af8df7e753d196c1262cb78e92ca872 ] adm1266_gpio_get(), adm1266_gpio_get_multiple(), and adm1266_gpio_dbg_show() all issue PMBus reads against the device but none of them take pmbus_lock. The pmbus_core framework holds pmbus_lock around its own multi-transaction sequences (notably the "set PAGE, then read paged register" pattern used by hwmon attributes), so an unlocked GPIO accessor can land between a PAGE write and the subsequent paged read in another thread and corrupt either side's view of the device state machine. Take pmbus_lock at the top of each of the three accessors via the scope-based guard(). The lock is uncontended in the common case and adds only a single mutex round-trip per call. Fixes: d98dfad35c38 ("hwmon: (pmbus/adm1266) Add support for GPIOs") Cc: stable@vger.kernel.org Signed-off-by: Abdurrahman Hussain Reviewed-by: Bartosz Golaszewski Link: https://lore.kernel.org/r/20260518-adm1266-gpio-fixes-v3-6-e425e4f88139@nexthop.ai Signed-off-by: Guenter Roeck [ open-coded each `guard(pmbus_lock)(data->client)` as explicit `pmbus_lock_interruptible()`/`pmbus_unlock()` ] Signed-off-by: Sasha Levin --- drivers/hwmon/pmbus/adm1266.c | 40 +++++++++++++++++++++++++++++------ 1 file changed, 34 insertions(+), 6 deletions(-) diff --git a/drivers/hwmon/pmbus/adm1266.c b/drivers/hwmon/pmbus/adm1266.c index 432a7088e22bbb..e9e2d4f32a6326 100644 --- a/drivers/hwmon/pmbus/adm1266.c +++ b/drivers/hwmon/pmbus/adm1266.c @@ -173,7 +173,12 @@ static int adm1266_gpio_get(struct gpio_chip *chip, unsigned int offset) else pmbus_cmd = ADM1266_PDIO_STATUS; + ret = pmbus_lock_interruptible(data->client); + if (ret) + return ret; + ret = i2c_smbus_read_block_data(data->client, pmbus_cmd, read_buf); + pmbus_unlock(data->client); if (ret < 0) return ret; if (ret < 2) @@ -195,11 +200,19 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask unsigned int gpio_nr; int ret; + ret = pmbus_lock_interruptible(data->client); + if (ret) + return ret; + ret = i2c_smbus_read_block_data(data->client, ADM1266_GPIO_STATUS, read_buf); - if (ret < 0) + if (ret < 0) { + pmbus_unlock(data->client); return ret; - if (ret < 2) + } + if (ret < 2) { + pmbus_unlock(data->client); return -EIO; + } status = read_buf[0] + (read_buf[1] << 8); @@ -210,10 +223,14 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask } ret = i2c_smbus_read_block_data(data->client, ADM1266_PDIO_STATUS, read_buf); - if (ret < 0) + if (ret < 0) { + pmbus_unlock(data->client); return ret; - if (ret < 2) + } + if (ret < 2) { + pmbus_unlock(data->client); return -EIO; + } status = read_buf[0] + (read_buf[1] << 8); @@ -222,6 +239,8 @@ static int adm1266_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask set_bit(gpio_nr, bits); } + pmbus_unlock(data->client); + return 0; } @@ -236,11 +255,16 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) int ret; int i; + if (pmbus_lock_interruptible(data->client)) + return; + for (i = 0; i < ADM1266_GPIO_NR; i++) { write_cmd = adm1266_gpio_mapping[i][1]; ret = adm1266_pmbus_block_xfer(data, ADM1266_GPIO_CONFIG, 1, &write_cmd, read_buf); - if (ret != 2) + if (ret != 2) { + pmbus_unlock(data->client); return; + } gpio_config = read_buf[0]; seq_puts(s, adm1266_names[i]); @@ -262,8 +286,10 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) write_cmd = 0xFF; ret = adm1266_pmbus_block_xfer(data, ADM1266_PDIO_CONFIG, 1, &write_cmd, read_buf); - if (ret != 32) + if (ret != 32) { + pmbus_unlock(data->client); return; + } for (i = 0; i < ADM1266_PDIO_NR; i++) { seq_puts(s, adm1266_names[ADM1266_GPIO_NR + i]); @@ -286,6 +312,8 @@ static void adm1266_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip) seq_puts(s, ")\n"); } + + pmbus_unlock(data->client); } static int adm1266_config_gpio(struct adm1266_data *data) -- 2.53.0