diff --git a/kernel/Kconfig b/kernel/Kconfig
index 758d2ab0e7d..aa1f4bc3bf3 100644
--- a/kernel/Kconfig
+++ b/kernel/Kconfig
@@ -147,9 +147,7 @@ config SCHED_CPU_MASK
 
 config MAIN_STACK_SIZE
 	int "Size of stack for initialization and main thread"
-	default 640 if RISCV32
 	default 2048 if COVERAGE_GCOV
-	default 1024 if X86
 	default 512 if ZTEST
 	default 1024
 	help
diff --git a/tests/kernel/mem_protect/stackprot/prj.conf b/tests/kernel/mem_protect/stackprot/prj.conf
index 7c488ecbd98..e49577e1cb1 100644
--- a/tests/kernel/mem_protect/stackprot/prj.conf
+++ b/tests/kernel/mem_protect/stackprot/prj.conf
@@ -3,4 +3,5 @@ CONFIG_STACK_CANARIES=y
 CONFIG_ENTROPY_GENERATOR=y
 CONFIG_TEST_RANDOM_GENERATOR=y
 CONFIG_MAIN_THREAD_PRIORITY=7
+CONFIG_MAIN_STACK_SIZE=640
 CONFIG_TEST_USERSPACE=y