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* [PATCH] pinctrl: renesas: rzt2h: fix invalid wait context
@ 2026-02-04 18:04 Cosmin Tanislav
  2026-02-04 19:14 ` Sebastian Andrzej Siewior
  0 siblings, 1 reply; 4+ messages in thread
From: Cosmin Tanislav @ 2026-02-04 18:04 UTC (permalink / raw)
  To: Geert Uytterhoeven, Linus Walleij, Sebastian Andrzej Siewior,
	Clark Williams, Steven Rostedt, Bartosz Golaszewski,
	Cosmin Tanislav
  Cc: linux-renesas-soc, linux-gpio, linux-kernel, linux-rt-devel

The following invalid wait context BUG is observed when running with
CONFIG_PROVE_LOCKING enabled.

This seems to stem from the fact that __setup_irq() takes a
raw_spinlock_t, while we take a spinlock_t inside gpiod_get_direction().

raw_spinlock_t is a strictly spinning lock, while spinlock_t can sleep
if PREEMPT_RT is enabled.

Switch to raw_spinlock_t to fix this.

[   20.641809] =============================
[   20.646336] [ BUG: Invalid wait context ]
[   20.650964] 6.19.0-rc8-next-20260202+ #417 Not tainted
[   20.656892] -----------------------------
[   20.661517] (udev-worker)/235 is trying to lock:
[   20.666842] ffff000182d4ab58 (&pctrl->lock){....}-{3:3}, at: rzt2h_gpio_get_direction+0x3c/0x150
[   20.676928] other info that might help us debug this:
[   20.682560] context-{5:5}
[   20.685572] 4 locks held by (udev-worker)/235:
[   20.690701]  #0: ffff000180b398f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0x10c/0x210
[   20.700480]  #1: ffff000186f41a60 (request_class){+.+.}-{4:4}, at: __setup_irq+0x10c/0x740
[   20.709952]  #2: ffff000186f418c8 (lock_class){....}-{2:2}, at: __setup_irq+0x12c/0x740
[   20.719057]  #3: ffff000182d4a690 (&gdev->srcu){.+.+}-{0:0}, at: gpiod_get_direction+0x40/0x24c
[   20.729135] stack backtrace:
[   20.732450] CPU: 2 UID: 0 PID: 235 Comm: (udev-worker) Not tainted 6.19.0-rc8-next-20260202+ #417 PREEMPT
[   20.732459] Hardware name: Renesas RZ/T2H EVK Board based on r9a09g077m44 (DT)
[   20.732464] Call trace:
[   20.732467]  show_stack+0x18/0x30 (C)
[   20.732479]  dump_stack_lvl+0x70/0x98
[   20.732489]  dump_stack+0x18/0x24
[   20.732497]  __lock_acquire+0x910/0x1594
[   20.732508]  lock_acquire+0x2f0/0x42c
[   20.732517]  _raw_spin_lock_irqsave+0x5c/0x94
[   20.732529]  rzt2h_gpio_get_direction+0x3c/0x150
[   20.732538]  gpiochip_get_direction+0x34/0x90
[   20.732547]  gpiod_get_direction+0xd8/0x24c
[   20.732556]  gpiochip_lock_as_irq+0x68/0x144
[   20.732565]  gpiochip_irq_domain_activate+0x18/0x30
[   20.732574]  __irq_domain_activate_irq+0x60/0xb0
[   20.732583]  irq_domain_activate_irq+0x34/0x5c
[   20.732593]  irq_activate+0x2c/0x38
[   20.732600]  __setup_irq+0x2d8/0x740
[   20.732610]  request_threaded_irq+0xb0/0x180
[   20.732620]  request_any_context_irq+0x58/0xac
[   20.732629]  devm_request_any_context_irq+0x78/0x160
[   20.732637]  gpio_keys_probe+0x344/0xb40 [gpio_keys]
[   20.732657]  platform_probe+0x5c/0xa4
[   20.732666]  really_probe+0xbc/0x2ac
[   20.732675]  __driver_probe_device+0x78/0x118
[   20.732684]  driver_probe_device+0x3c/0x170
[   20.732693]  __driver_attach+0x118/0x210
[   20.732701]  bus_for_each_dev+0x7c/0xdc
[   20.732710]  driver_attach+0x24/0x3c
[   20.732718]  bus_add_driver+0xe4/0x204
[   20.732727]  driver_register+0x68/0x124
[   20.732736]  __platform_driver_register+0x20/0x2c
[   20.732746]  gpio_keys_init+0x20/0x1000 [gpio_keys]
[   20.732758]  do_one_initcall+0x7c/0x530
[   20.732770]  do_init_module+0x54/0x23c
[   20.732780]  load_module+0x181c/0x1ed0
[   20.732789]  init_module_from_file+0xd8/0xfc
[   20.732797]  idempotent_init_module+0x1e0/0x2d0
[   20.732806]  __arm64_sys_finit_module+0x60/0xa4
[   20.732814]  invoke_syscall.constprop.0+0x40/0xf0
[   20.732824]  el0_svc_common.constprop.0+0xb8/0xd8
[   20.732832]  do_el0_svc+0x1c/0x28
[   20.732839]  el0_svc+0x4c/0x2dc
[   20.732850]  el0t_64_sync_handler+0xa0/0xe4
[   20.732860]  el0t_64_sync+0x198/0x19c

Fixes: 829dde3369a9 ("pinctrl: renesas: rzt2h: Add GPIO IRQ chip to handle interrupts")
Signed-off-by: Cosmin Tanislav <cosmin-gabriel.tanislav.xa@renesas.com>
---
 drivers/pinctrl/renesas/pinctrl-rzt2h.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/pinctrl/renesas/pinctrl-rzt2h.c b/drivers/pinctrl/renesas/pinctrl-rzt2h.c
index 9949108a35bb..d810dc0dae95 100644
--- a/drivers/pinctrl/renesas/pinctrl-rzt2h.c
+++ b/drivers/pinctrl/renesas/pinctrl-rzt2h.c
@@ -85,7 +85,7 @@ struct rzt2h_pinctrl {
 	struct gpio_chip		gpio_chip;
 	struct pinctrl_gpio_range	gpio_range;
 	DECLARE_BITMAP(used_irqs, RZT2H_INTERRUPTS_NUM);
-	spinlock_t			lock; /* lock read/write registers */
+	raw_spinlock_t			lock; /* lock read/write registers */
 	struct mutex			mutex; /* serialize adding groups and functions */
 	bool				safety_port_enabled;
 	atomic_t			wakeup_path;
@@ -145,7 +145,7 @@ static void rzt2h_pinctrl_set_pfc_mode(struct rzt2h_pinctrl *pctrl,
 	u64 reg64;
 	u16 reg16;
 
-	guard(spinlock_irqsave)(&pctrl->lock);
+	guard(raw_spinlock_irqsave)(&pctrl->lock);
 
 	/* Set pin to 'Non-use (Hi-Z input protection)'  */
 	reg16 = rzt2h_pinctrl_readw(pctrl, port, PM(port));
@@ -474,7 +474,7 @@ static int rzt2h_gpio_request(struct gpio_chip *chip, unsigned int offset)
 	if (ret)
 		return ret;
 
-	guard(spinlock_irqsave)(&pctrl->lock);
+	guard(raw_spinlock_irqsave)(&pctrl->lock);
 
 	/* Select GPIO mode in PMC Register */
 	rzt2h_pinctrl_set_gpio_en(pctrl, port, bit, true);
@@ -487,7 +487,7 @@ static void rzt2h_gpio_set_direction(struct rzt2h_pinctrl *pctrl, u32 port,
 {
 	u16 reg;
 
-	guard(spinlock_irqsave)(&pctrl->lock);
+	guard(raw_spinlock_irqsave)(&pctrl->lock);
 
 	reg = rzt2h_pinctrl_readw(pctrl, port, PM(port));
 	reg &= ~PM_PIN_MASK(bit);
@@ -509,7 +509,7 @@ static int rzt2h_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
 	if (ret)
 		return ret;
 
-	guard(spinlock_irqsave)(&pctrl->lock);
+	guard(raw_spinlock_irqsave)(&pctrl->lock);
 
 	if (rzt2h_pinctrl_readb(pctrl, port, PMC(port)) & BIT(bit)) {
 		/*
@@ -547,7 +547,7 @@ static int rzt2h_gpio_set(struct gpio_chip *chip, unsigned int offset,
 	u8 bit = RZT2H_PIN_ID_TO_PIN(offset);
 	u8 reg;
 
-	guard(spinlock_irqsave)(&pctrl->lock);
+	guard(raw_spinlock_irqsave)(&pctrl->lock);
 
 	reg = rzt2h_pinctrl_readb(pctrl, port, P(port));
 	if (value)
@@ -964,7 +964,7 @@ static int rzt2h_pinctrl_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	spin_lock_init(&pctrl->lock);
+	raw_spin_lock_init(&pctrl->lock);
 	mutex_init(&pctrl->mutex);
 	platform_set_drvdata(pdev, pctrl);
 
-- 
2.52.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread

* Re: [PATCH] pinctrl: renesas: rzt2h: fix invalid wait context
  2026-02-04 18:04 [PATCH] pinctrl: renesas: rzt2h: fix invalid wait context Cosmin Tanislav
@ 2026-02-04 19:14 ` Sebastian Andrzej Siewior
  2026-02-04 19:53   ` Cosmin-Gabriel Tanislav
  0 siblings, 1 reply; 4+ messages in thread
From: Sebastian Andrzej Siewior @ 2026-02-04 19:14 UTC (permalink / raw)
  To: Cosmin Tanislav
  Cc: Geert Uytterhoeven, Linus Walleij, Clark Williams, Steven Rostedt,
	Bartosz Golaszewski, linux-renesas-soc, linux-gpio, linux-kernel,
	linux-rt-devel

On 2026-02-04 20:04:48 [+0200], Cosmin Tanislav wrote:
> The following invalid wait context BUG is observed when running with
> CONFIG_PROVE_LOCKING enabled.
> 
> This seems to stem from the fact that __setup_irq() takes a
> raw_spinlock_t, while we take a spinlock_t inside gpiod_get_direction().

From the backtrace yes. It is more that the irqchip used interrupt chip
needs to be able to mask interrupts in hardirq context which it needs a
raw_spinlock_t.

> raw_spinlock_t is a strictly spinning lock, while spinlock_t can sleep
> if PREEMPT_RT is enabled.
> 
> Switch to raw_spinlock_t to fix this.
> 
> [   20.641809] =============================
> [   20.646336] [ BUG: Invalid wait context ]
> [   20.650964] 6.19.0-rc8-next-20260202+ #417 Not tainted
> [   20.656892] -----------------------------
> [   20.661517] (udev-worker)/235 is trying to lock:
> [   20.666842] ffff000182d4ab58 (&pctrl->lock){....}-{3:3}, at: rzt2h_gpio_get_direction+0x3c/0x150
> [   20.676928] other info that might help us debug this:
> [   20.682560] context-{5:5}
> [   20.685572] 4 locks held by (udev-worker)/235:
> [   20.690701]  #0: ffff000180b398f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0x10c/0x210
> [   20.700480]  #1: ffff000186f41a60 (request_class){+.+.}-{4:4}, at: __setup_irq+0x10c/0x740
> [   20.709952]  #2: ffff000186f418c8 (lock_class){....}-{2:2}, at: __setup_irq+0x12c/0x740
> [   20.719057]  #3: ffff000182d4a690 (&gdev->srcu){.+.+}-{0:0}, at: gpiod_get_direction+0x40/0x24c
> [   20.729135] stack backtrace:
> [   20.732450] CPU: 2 UID: 0 PID: 235 Comm: (udev-worker) Not tainted 6.19.0-rc8-next-20260202+ #417 PREEMPT
> [   20.732459] Hardware name: Renesas RZ/T2H EVK Board based on r9a09g077m44 (DT)
> [   20.732464] Call trace:
> [   20.732467]  show_stack+0x18/0x30 (C)
> [   20.732479]  dump_stack_lvl+0x70/0x98
> [   20.732489]  dump_stack+0x18/0x24
> [   20.732497]  __lock_acquire+0x910/0x1594
> [   20.732508]  lock_acquire+0x2f0/0x42c
> [   20.732517]  _raw_spin_lock_irqsave+0x5c/0x94
> [   20.732529]  rzt2h_gpio_get_direction+0x3c/0x150
> [   20.732538]  gpiochip_get_direction+0x34/0x90
> [   20.732547]  gpiod_get_direction+0xd8/0x24c
> [   20.732556]  gpiochip_lock_as_irq+0x68/0x144
> [   20.732565]  gpiochip_irq_domain_activate+0x18/0x30
> [   20.732574]  __irq_domain_activate_irq+0x60/0xb0
> [   20.732583]  irq_domain_activate_irq+0x34/0x5c
> [   20.732593]  irq_activate+0x2c/0x38
> [   20.732600]  __setup_irq+0x2d8/0x740
> [   20.732610]  request_threaded_irq+0xb0/0x180
> [   20.732620]  request_any_context_irq+0x58/0xac
> [   20.732629]  devm_request_any_context_irq+0x78/0x160
> [   20.732637]  gpio_keys_probe+0x344/0xb40 [gpio_keys]
> [   20.732657]  platform_probe+0x5c/0xa4
> [   20.732666]  really_probe+0xbc/0x2ac
> [   20.732675]  __driver_probe_device+0x78/0x118
> [   20.732684]  driver_probe_device+0x3c/0x170
> [   20.732693]  __driver_attach+0x118/0x210
> [   20.732701]  bus_for_each_dev+0x7c/0xdc
> [   20.732710]  driver_attach+0x24/0x3c
> [   20.732718]  bus_add_driver+0xe4/0x204
> [   20.732727]  driver_register+0x68/0x124
> [   20.732736]  __platform_driver_register+0x20/0x2c
> [   20.732746]  gpio_keys_init+0x20/0x1000 [gpio_keys]
> [   20.732758]  do_one_initcall+0x7c/0x530
> [   20.732770]  do_init_module+0x54/0x23c
> [   20.732780]  load_module+0x181c/0x1ed0
> [   20.732789]  init_module_from_file+0xd8/0xfc
> [   20.732797]  idempotent_init_module+0x1e0/0x2d0
> [   20.732806]  __arm64_sys_finit_module+0x60/0xa4
> [   20.732814]  invoke_syscall.constprop.0+0x40/0xf0
> [   20.732824]  el0_svc_common.constprop.0+0xb8/0xd8
> [   20.732832]  do_el0_svc+0x1c/0x28
> [   20.732839]  el0_svc+0x4c/0x2dc
> [   20.732850]  el0t_64_sync_handler+0xa0/0xe4
> [   20.732860]  el0t_64_sync+0x198/0x19c

Please get rid of this backtrace. It adds no value to the description.

> Fixes: 829dde3369a9 ("pinctrl: renesas: rzt2h: Add GPIO IRQ chip to handle interrupts")
> Signed-off-by: Cosmin Tanislav <cosmin-gabriel.tanislav.xa@renesas.com>

Sebastian

^ permalink raw reply	[flat|nested] 4+ messages in thread

* RE: [PATCH] pinctrl: renesas: rzt2h: fix invalid wait context
  2026-02-04 19:14 ` Sebastian Andrzej Siewior
@ 2026-02-04 19:53   ` Cosmin-Gabriel Tanislav
  2026-02-04 20:00     ` Sebastian Andrzej Siewior
  0 siblings, 1 reply; 4+ messages in thread
From: Cosmin-Gabriel Tanislav @ 2026-02-04 19:53 UTC (permalink / raw)
  To: Sebastian Andrzej Siewior
  Cc: Geert Uytterhoeven, Linus Walleij, Clark Williams, Steven Rostedt,
	Bartosz Golaszewski, linux-renesas-soc@vger.kernel.org,
	linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-rt-devel@lists.linux.dev

> From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> Sent: Wednesday, February 4, 2026 9:14 PM
> 
> On 2026-02-04 20:04:48 [+0200], Cosmin Tanislav wrote:
> > The following invalid wait context BUG is observed when running with
> > CONFIG_PROVE_LOCKING enabled.
> >
> > This seems to stem from the fact that __setup_irq() takes a
> > raw_spinlock_t, while we take a spinlock_t inside gpiod_get_direction().
> 
> From the backtrace yes. It is more that the irqchip used interrupt chip
> needs to be able to mask interrupts in hardirq context which it needs a
> raw_spinlock_t.
> 

Would you like me to reword the commit message? I only analyzed why it
happens, I didn't investigate why it needs to happen. :D

> > raw_spinlock_t is a strictly spinning lock, while spinlock_t can sleep
> > if PREEMPT_RT is enabled.
> >
> > Switch to raw_spinlock_t to fix this.
> >
> > [   20.641809] =============================
> > [   20.646336] [ BUG: Invalid wait context ]
> > [   20.650964] 6.19.0-rc8-next-20260202+ #417 Not tainted
> > [   20.656892] -----------------------------
> > [   20.661517] (udev-worker)/235 is trying to lock:
> > [   20.666842] ffff000182d4ab58 (&pctrl->lock){....}-{3:3}, at: rzt2h_gpio_get_direction+0x3c/0x150
> > [   20.676928] other info that might help us debug this:
> > [   20.682560] context-{5:5}
> > [   20.685572] 4 locks held by (udev-worker)/235:
> > [   20.690701]  #0: ffff000180b398f8 (&dev->mutex){....}-{4:4}, at: __driver_attach+0x10c/0x210
> > [   20.700480]  #1: ffff000186f41a60 (request_class){+.+.}-{4:4}, at: __setup_irq+0x10c/0x740
> > [   20.709952]  #2: ffff000186f418c8 (lock_class){....}-{2:2}, at: __setup_irq+0x12c/0x740
> > [   20.719057]  #3: ffff000182d4a690 (&gdev->srcu){.+.+}-{0:0}, at: gpiod_get_direction+0x40/0x24c
> > [   20.729135] stack backtrace:
> > [   20.732450] CPU: 2 UID: 0 PID: 235 Comm: (udev-worker) Not tainted 6.19.0-rc8-next-20260202+ #417
> PREEMPT
> > [   20.732459] Hardware name: Renesas RZ/T2H EVK Board based on r9a09g077m44 (DT)
> > [   20.732464] Call trace:
> > [   20.732467]  show_stack+0x18/0x30 (C)
> > [   20.732479]  dump_stack_lvl+0x70/0x98
> > [   20.732489]  dump_stack+0x18/0x24
> > [   20.732497]  __lock_acquire+0x910/0x1594
> > [   20.732508]  lock_acquire+0x2f0/0x42c
> > [   20.732517]  _raw_spin_lock_irqsave+0x5c/0x94
> > [   20.732529]  rzt2h_gpio_get_direction+0x3c/0x150
> > [   20.732538]  gpiochip_get_direction+0x34/0x90
> > [   20.732547]  gpiod_get_direction+0xd8/0x24c
> > [   20.732556]  gpiochip_lock_as_irq+0x68/0x144
> > [   20.732565]  gpiochip_irq_domain_activate+0x18/0x30
> > [   20.732574]  __irq_domain_activate_irq+0x60/0xb0
> > [   20.732583]  irq_domain_activate_irq+0x34/0x5c
> > [   20.732593]  irq_activate+0x2c/0x38
> > [   20.732600]  __setup_irq+0x2d8/0x740
> > [   20.732610]  request_threaded_irq+0xb0/0x180
> > [   20.732620]  request_any_context_irq+0x58/0xac
> > [   20.732629]  devm_request_any_context_irq+0x78/0x160
> > [   20.732637]  gpio_keys_probe+0x344/0xb40 [gpio_keys]
> > [   20.732657]  platform_probe+0x5c/0xa4
> > [   20.732666]  really_probe+0xbc/0x2ac
> > [   20.732675]  __driver_probe_device+0x78/0x118
> > [   20.732684]  driver_probe_device+0x3c/0x170
> > [   20.732693]  __driver_attach+0x118/0x210
> > [   20.732701]  bus_for_each_dev+0x7c/0xdc
> > [   20.732710]  driver_attach+0x24/0x3c
> > [   20.732718]  bus_add_driver+0xe4/0x204
> > [   20.732727]  driver_register+0x68/0x124
> > [   20.732736]  __platform_driver_register+0x20/0x2c
> > [   20.732746]  gpio_keys_init+0x20/0x1000 [gpio_keys]
> > [   20.732758]  do_one_initcall+0x7c/0x530
> > [   20.732770]  do_init_module+0x54/0x23c
> > [   20.732780]  load_module+0x181c/0x1ed0
> > [   20.732789]  init_module_from_file+0xd8/0xfc
> > [   20.732797]  idempotent_init_module+0x1e0/0x2d0
> > [   20.732806]  __arm64_sys_finit_module+0x60/0xa4
> > [   20.732814]  invoke_syscall.constprop.0+0x40/0xf0
> > [   20.732824]  el0_svc_common.constprop.0+0xb8/0xd8
> > [   20.732832]  do_el0_svc+0x1c/0x28
> > [   20.732839]  el0_svc+0x4c/0x2dc
> > [   20.732850]  el0t_64_sync_handler+0xa0/0xe4
> > [   20.732860]  el0t_64_sync+0x198/0x19c
> 
> Please get rid of this backtrace. It adds no value to the description.
> 

I will remove it.

> > Fixes: 829dde3369a9 ("pinctrl: renesas: rzt2h: Add GPIO IRQ chip to handle interrupts")
> > Signed-off-by: Cosmin Tanislav <cosmin-gabriel.tanislav.xa@renesas.com>
> 
> Sebastian

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: RE: [PATCH] pinctrl: renesas: rzt2h: fix invalid wait context
  2026-02-04 19:53   ` Cosmin-Gabriel Tanislav
@ 2026-02-04 20:00     ` Sebastian Andrzej Siewior
  0 siblings, 0 replies; 4+ messages in thread
From: Sebastian Andrzej Siewior @ 2026-02-04 20:00 UTC (permalink / raw)
  To: Cosmin-Gabriel Tanislav
  Cc: Geert Uytterhoeven, Linus Walleij, Clark Williams, Steven Rostedt,
	Bartosz Golaszewski, linux-renesas-soc@vger.kernel.org,
	linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-rt-devel@lists.linux.dev

On 2026-02-04 19:53:36 [+0000], Cosmin-Gabriel Tanislav wrote:
> > From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
> > Sent: Wednesday, February 4, 2026 9:14 PM
> > 
> > On 2026-02-04 20:04:48 [+0200], Cosmin Tanislav wrote:
> > > The following invalid wait context BUG is observed when running with
> > > CONFIG_PROVE_LOCKING enabled.
> > >
> > > This seems to stem from the fact that __setup_irq() takes a
> > > raw_spinlock_t, while we take a spinlock_t inside gpiod_get_direction().
> > 
> > From the backtrace yes. It is more that the irqchip used interrupt chip
> > needs to be able to mask interrupts in hardirq context which it needs a
> > raw_spinlock_t.
> > 
> 
> Would you like me to reword the commit message? I only analyzed why it
> happens, I didn't investigate why it needs to happen. :D

It did explain. It would make sense to include the reasoning and not
symptoms.

Sebastian

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2026-02-04 20:00 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2026-02-04 18:04 [PATCH] pinctrl: renesas: rzt2h: fix invalid wait context Cosmin Tanislav
2026-02-04 19:14 ` Sebastian Andrzej Siewior
2026-02-04 19:53   ` Cosmin-Gabriel Tanislav
2026-02-04 20:00     ` Sebastian Andrzej Siewior

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