diff --git a/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/defconfig b/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/defconfig
index c53d1d77b5..53065c67b0 100644
--- a/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/defconfig
+++ b/boards/arm/stm32/stm32f4discovery/configs/testlibcxx/defconfig
@@ -42,7 +42,8 @@ CONFIG_STM32_JTAG_SW_ENABLE=y
 CONFIG_STM32_USART2=y
 CONFIG_SYMTAB_ORDEREDBYNAME=y
 CONFIG_SYSTEM_NSH=y
-CONFIG_TLS_NELEM=4
+CONFIG_TLS_NELEM=16
+CONFIG_TLS_TASK_NELEM=8
 CONFIG_USART2_RXBUFSIZE=128
 CONFIG_USART2_SERIAL_CONSOLE=y
 CONFIG_USART2_TXBUFSIZE=128