From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- drivers/pinctrl/pinctrl-utils.c | 129 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 129 insertions(+) create mode 100644 drivers/pinctrl/pinctrl-utils.c (limited to 'drivers/pinctrl/pinctrl-utils.c') diff --git a/drivers/pinctrl/pinctrl-utils.c b/drivers/pinctrl/pinctrl-utils.c new file mode 100644 index 000000000..b880e44b8 --- /dev/null +++ b/drivers/pinctrl/pinctrl-utils.c @@ -0,0 +1,129 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Utils functions to implement the pincontrol driver. + * + * Copyright (c) 2013, NVIDIA Corporation. + * + * Author: Laxman Dewangan + */ +#include +#include +#include +#include +#include + +#include + +#include "core.h" +#include "pinctrl-utils.h" + +int pinctrl_utils_reserve_map(struct pinctrl_dev *pctldev, + struct pinctrl_map **map, unsigned int *reserved_maps, + unsigned int *num_maps, unsigned int reserve) +{ + unsigned int old_num = *reserved_maps; + unsigned int new_num = *num_maps + reserve; + struct pinctrl_map *new_map; + + if (old_num >= new_num) + return 0; + + new_map = krealloc_array(*map, new_num, sizeof(*new_map), GFP_KERNEL); + if (!new_map) { + dev_err(pctldev->dev, "krealloc(map) failed\n"); + return -ENOMEM; + } + + memset(new_map + old_num, 0, (new_num - old_num) * sizeof(*new_map)); + + *map = new_map; + *reserved_maps = new_num; + return 0; +} +EXPORT_SYMBOL_GPL(pinctrl_utils_reserve_map); + +int pinctrl_utils_add_map_mux(struct pinctrl_dev *pctldev, + struct pinctrl_map **map, unsigned int *reserved_maps, + unsigned int *num_maps, const char *group, + const char *function) +{ + if (WARN_ON(*num_maps == *reserved_maps)) + return -ENOSPC; + + (*map)[*num_maps].type = PIN_MAP_TYPE_MUX_GROUP; + (*map)[*num_maps].data.mux.group = group; + (*map)[*num_maps].data.mux.function = function; + (*num_maps)++; + + return 0; +} +EXPORT_SYMBOL_GPL(pinctrl_utils_add_map_mux); + +int pinctrl_utils_add_map_configs(struct pinctrl_dev *pctldev, + struct pinctrl_map **map, unsigned int *reserved_maps, + unsigned int *num_maps, const char *group, + unsigned long *configs, unsigned int num_configs, + enum pinctrl_map_type type) +{ + unsigned long *dup_configs; + + if (WARN_ON(*num_maps == *reserved_maps)) + return -ENOSPC; + + dup_configs = kmemdup_array(configs, num_configs, + sizeof(*dup_configs), GFP_KERNEL); + if (!dup_configs) + return -ENOMEM; + + (*map)[*num_maps].type = type; + (*map)[*num_maps].data.configs.group_or_pin = group; + (*map)[*num_maps].data.configs.configs = dup_configs; + (*map)[*num_maps].data.configs.num_configs = num_configs; + (*num_maps)++; + + return 0; +} +EXPORT_SYMBOL_GPL(pinctrl_utils_add_map_configs); + +int pinctrl_utils_add_config(struct pinctrl_dev *pctldev, + unsigned long **configs, unsigned int *num_configs, + unsigned long config) +{ + unsigned int old_num = *num_configs; + unsigned int new_num = old_num + 1; + unsigned long *new_configs; + + new_configs = krealloc(*configs, sizeof(*new_configs) * new_num, + GFP_KERNEL); + if (!new_configs) { + dev_err(pctldev->dev, "krealloc(configs) failed\n"); + return -ENOMEM; + } + + new_configs[old_num] = config; + + *configs = new_configs; + *num_configs = new_num; + + return 0; +} +EXPORT_SYMBOL_GPL(pinctrl_utils_add_config); + +void pinctrl_utils_free_map(struct pinctrl_dev *pctldev, + struct pinctrl_map *map, unsigned int num_maps) +{ + int i; + + for (i = 0; i < num_maps; i++) { + switch (map[i].type) { + case PIN_MAP_TYPE_CONFIGS_GROUP: + case PIN_MAP_TYPE_CONFIGS_PIN: + kfree(map[i].data.configs.configs); + break; + default: + break; + } + } + kfree(map); +} +EXPORT_SYMBOL_GPL(pinctrl_utils_free_map); -- cgit v1.3.1