diff --git a/os/hal/ports/STM32/STM32L4xx/ext_lld_isr.h b/os/hal/ports/STM32/STM32L4xx/ext_lld_isr.h
index ceb2a8f91..3e9d686b6 100644
--- a/os/hal/ports/STM32/STM32L4xx/ext_lld_isr.h
+++ b/os/hal/ports/STM32/STM32L4xx/ext_lld_isr.h
@@ -95,13 +95,6 @@
 #define STM32_EXT_EXTI16_IRQ_PRIORITY       6
 #endif
 
-/**
- * @brief   EXTI17 interrupt priority level setting.
- */
-#if !defined(STM32_EXT_EXTI17_IRQ_PRIORITY) || defined(__DOXYGEN__)
-#define STM32_EXT_EXTI17_IRQ_PRIORITY       6
-#endif
-
 /**
  * @brief   EXTI18 interrupt priority level setting.
  */
diff --git a/readme.txt b/readme.txt
index f3d5f1cc0..8cb06a397 100644
--- a/readme.txt
+++ b/readme.txt
@@ -76,6 +76,7 @@
 - ALL: Startup files relicensed under Apache 2.0.
 - RT:  Added RT-STM32L476-DISCOVERY demo.
 - HAL: Updated all STM32F476 mcuconf.h files.
+- HAL: Fixed wrong definition in STM32L4 ext_lld_isr.h (bug #717).
 - HAL: Fixed wrong definitions in STM32F746 mcuconf.h files (bug #716)
 - RT:  Fixed wrong SysTick initialization in generic demos (bug #715).
 - NIL: Fixed wrong SysTick initialization in generic demos (bug #715).