@@ -14,6 +14,7 @@
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinconf.h>
@@ -121,7 +122,8 @@ 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 };
@@ -320,11 +322,13 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev,
name = np->name;
}
+ mutex_lock(&pctrl->mutex);
+
/* 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;
}
/*
@@ -338,6 +342,8 @@ 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;
@@ -349,6 +355,8 @@ static int rzv2m_dt_subnode_to_map(struct pinctrl_dev *pctldev,
remove_group:
pinctrl_generic_remove_group(pctldev, gsel);
+unlock:
+ mutex_unlock(&pctrl->mutex);
done:
*index = idx;
kfree(configs);
@@ -1070,6 +1078,7 @@ static int rzv2m_pinctrl_probe(struct platform_device *pdev)
}
spin_lock_init(&pctrl->lock);
+ mutex_init(&pctrl->mutex);
platform_set_drvdata(pdev, pctrl);
commit f982b9d57e7f834138fc908804fe66f646f2b108 upstream. Fix the below random NULL pointer crash during boot by serializing pinctrl group and function creation/remove calls 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 a comment for lock. Fixes: 92a9b8252576 ("pinctrl: renesas: Add RZ/V2M pin and gpio controller driver") Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20230815131558.33787-3-biju.das.jz@bp.renesas.com Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- drivers/pinctrl/renesas/pinctrl-rzv2m.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)