6.1-stable review patch. If anyone has any objections, please let me know.
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From: Biju Das biju.das.jz@bp.renesas.com
[ Upstream commit 661efa2284bbc2338da0424e219603f034072c74 ]
Fix the below random NULL pointer crash during boot by serializing pinctrl group and function creation/remove calls in rzg2l_dt_subnode_to_map() with mutex lock.
Crash log: 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 rzg2l_dt_subnode_to_map+0x314/0x44c rzg2l_dt_node_to_map+0x164/0x194 pinctrl_dt_to_map+0x218/0x37c create_pinctrl+0x70/0x3d8
While at it, add comments for bitmap_lock and lock.
Fixes: c4c4637eb57f ("pinctrl: renesas: Add RZ/G2L pin and gpio controller driver") Tested-by: Chris Paterson Chris.Paterson2@renesas.com 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/20230815131558.33787-2-biju.das.jz@bp.renesas.com Signed-off-by: Geert Uytterhoeven geert+renesas@glider.be Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/pinctrl/renesas/pinctrl-rzg2l.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/pinctrl/renesas/pinctrl-rzg2l.c b/drivers/pinctrl/renesas/pinctrl-rzg2l.c index fd11d28e5a1e4..2a617832a7e60 100644 --- a/drivers/pinctrl/renesas/pinctrl-rzg2l.c +++ b/drivers/pinctrl/renesas/pinctrl-rzg2l.c @@ -11,6 +11,7 @@ #include <linux/io.h> #include <linux/interrupt.h> #include <linux/module.h> +#include <linux/mutex.h> #include <linux/of_device.h> #include <linux/of_irq.h> #include <linux/pinctrl/pinconf-generic.h> @@ -146,10 +147,11 @@ struct rzg2l_pinctrl { struct gpio_chip gpio_chip; struct pinctrl_gpio_range gpio_range; DECLARE_BITMAP(tint_slot, RZG2L_TINT_MAX_INTERRUPT); - spinlock_t bitmap_lock; + spinlock_t bitmap_lock; /* protect tint_slot bitmap */ unsigned int hwirq[RZG2L_TINT_MAX_INTERRUPT];
- spinlock_t lock; + spinlock_t lock; /* lock read/write registers */ + struct mutex mutex; /* serialize adding groups and functions */ };
static const unsigned int iolh_groupa_mA[] = { 2, 4, 8, 12 }; @@ -359,11 +361,13 @@ static int rzg2l_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; }
/* @@ -377,6 +381,8 @@ static int rzg2l_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; @@ -388,6 +394,8 @@ static int rzg2l_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); @@ -1501,6 +1509,7 @@ static int rzg2l_pinctrl_probe(struct platform_device *pdev)
spin_lock_init(&pctrl->lock); spin_lock_init(&pctrl->bitmap_lock); + mutex_init(&pctrl->mutex);
platform_set_drvdata(pdev, pctrl);