From d31fbbade43f880b7e59e2b3a72722fe2725d93f Mon Sep 17 00:00:00 2001 From: Ju Nan Date: Fri, 21 Aug 2026 10:47:57 +0800 Subject: [PATCH] irqchip/stm32mp-exti: Fix the unit of the hwspinlock timeout HWSPNLCK_TIMEOUT is passed to hwspin_lock_timeout_in_atomic(), whose timeout argument is in milliseconds, not microseconds: atomic_delay += HWSPINLOCK_RETRY_DELAY_US; if (atomic_delay > to * 1000) return -ETIMEDOUT; So stm32mp_exti_set_type() asks for a 1 second timeout where the comment next to the macro says it wants 1 millisecond. The semaphore is polled with udelay() from a section that holds chip_data->rlock, a raw_spinlock_t, so preemption stays disabled for the whole wait on every configuration, PREEMPT_RT included. The hwspinlock core documents this explicitly: If the mode is HWLOCK_IN_ATOMIC (called from an atomic context) the timeout is handled with busy-waiting delays, hence shall not exceed few msecs. Fixes: 5257169ade8c ("irqchip/stm32-exti: Use the hwspin_lock_timeout_in_atomic() API") Signed-off-by: Ju Nan Signed-off-by: Thomas Gleixner Reviewed-by: Radu Rendec Reviewed-by: Antonio Borneo Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260821024756.24927-2-junan76@163.com --- drivers/irqchip/irq-stm32mp-exti.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/irqchip/irq-stm32mp-exti.c b/drivers/irqchip/irq-stm32mp-exti.c index bf3a2def69ca..a19e91fbd010 100644 --- a/drivers/irqchip/irq-stm32mp-exti.c +++ b/drivers/irqchip/irq-stm32mp-exti.c @@ -22,7 +22,7 @@ #define IRQS_PER_BANK 32 -#define HWSPNLCK_TIMEOUT 1000 /* usec */ +#define HWSPNLCK_TIMEOUT_MS 1 #define EXTI_EnCIDCFGR(n) (0x180 + (n) * 4) #define EXTI_HWCFGR1 0x3f0 @@ -376,7 +376,7 @@ static int stm32mp_exti_set_type(struct irq_data *d, unsigned int type) raw_spin_lock(&chip_data->rlock); if (hwlock) { - err = hwspin_lock_timeout_in_atomic(hwlock, HWSPNLCK_TIMEOUT); + err = hwspin_lock_timeout_in_atomic(hwlock, HWSPNLCK_TIMEOUT_MS); if (err) { pr_err("%s can't get hwspinlock (%d)\n", __func__, err); goto unlock;