@@ -14,6 +14,7 @@
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
@@ -123,7 +124,8 @@ struct rzv2m_pinctrl {
struct gpio_chip gpio_chip;
struct pinctrl_gpio_range gpio_range;
- spinlock_t lock;
+ spinlock_t lock; /* lock read/write registers */
+ struct mutex mutex; /* serialize adding groups and functions */
};
static const unsigned int drv_1_8V_group2_uA[] = { 1800, 3800, 7800, 11000 };
@@ -269,28 +271,6 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev,
if (num_pins)
nmaps += num_pins;
- maps = krealloc_array(maps, nmaps, sizeof(*maps), GFP_KERNEL);
- if (!maps) {
- ret = -ENOMEM;
- goto done;
- }
-
- *map = maps;
- *num_maps = nmaps;
- if (num_pins) {
- of_property_for_each_string(np, "pins", prop, pin) {
- ret = rzv2m_map_add_config(&maps[idx], pin,
- PIN_MAP_TYPE_CONFIGS_PIN,
- configs, num_configs);
- if (ret < 0)
- goto done;
-
- idx++;
- }
- ret = 0;
- goto done;
- }
-
pins = devm_kcalloc(pctrl->dev, num_pinmux, sizeof(*pins), GFP_KERNEL);
psel_val = devm_kcalloc(pctrl->dev, num_pinmux, sizeof(*psel_val),
GFP_KERNEL);
@@ -322,11 +302,34 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev,
name = np->name;
}
+ mutex_lock(&pctrl->mutex);
+ maps = krealloc_array(maps, nmaps, sizeof(*maps), GFP_KERNEL);
+ if (!maps) {
+ ret = -ENOMEM;
+ goto unlock_and_done;
+ }
+
+ *map = maps;
+ *num_maps = nmaps;
+ if (num_pins) {
+ of_property_for_each_string(np, "pins", prop, pin) {
+ ret = rzv2m_map_add_config(&maps[idx], pin,
+ PIN_MAP_TYPE_CONFIGS_PIN,
+ configs, num_configs);
+ if (ret < 0)
+ goto unlock_and_done;
+
+ idx++;
+ }
+ ret = 0;
+ goto unlock_and_done;
+ }
+
/* Register a single pin group listing all the pins we read from DT */
gsel = pinctrl_generic_add_group(pctldev, name, pins, num_pinmux, NULL);
if (gsel < 0) {
ret = gsel;
- goto done;
+ goto unlock_and_done;
}
/*
@@ -340,6 +343,8 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev,
goto remove_group;
}
+ mutex_unlock(&pctrl->mutex);
+
maps[idx].type = PIN_MAP_TYPE_MUX_GROUP;
maps[idx].data.mux.group = name;
maps[idx].data.mux.function = name;
@@ -351,6 +356,8 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev,
remove_group:
pinctrl_generic_remove_group(pctldev, gsel);
+unlock_and_done:
+ mutex_unlock(&pctrl->mutex);
done:
*index = idx;
kfree(configs);
@@ -1065,6 +1072,7 @@ static int rzv2m_pinctrl_probe(struct platform_device *pdev)
"failed to enable GPIO clk\n");
spin_lock_init(&pctrl->lock);
+ mutex_init(&pctrl->mutex);
platform_set_drvdata(pdev, pctrl);
Fix the below random NULL pointer crash during boot by serializing groups and functions creation in rzv2m_dt_subnode_to_map() with mutex lock. Crash logs: pc : __pi_strcmp+0x20/0x140 lr : pinmux_func_name_to_selector+0x68/0xa4 Call trace: __pi_strcmp+0x20/0x140 pinmux_generic_add_function+0x34/0xcc rzv2m_dt_subnode_to_map+0x2e4/0x418 rzv2m_dt_node_to_map+0x15c/0x18c pinctrl_dt_to_map+0x218/0x37c create_pinctrl+0x70/0x3d8 While at it, add comment for lock. Fixes: 92a9b8252576 ("pinctrl: renesas: Add RZ/V2M pin and gpio controller driver") Cc: stable@kernel.org Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- v2->v3: * Added comment for lock. * Moved map allocation down to reduce lock section. * Added locks for maps and pinctrl group and function creation/remove calls * Added unlock_and_done label for lock error path. v1->v2: * Updated crash logs as per submitting patches doc. --- drivers/pinctrl/renesas/pinctrl-rzv2m.c | 56 ++++++++++++++----------- 1 file changed, 32 insertions(+), 24 deletions(-)