tests: kernel: fatal: Add ARC-specific stack protection test

Add ARC-specific variant of kernel.common.stack_protection test that
omits frame pointers to work around GNU toolchain code generation issue.

The GNU toolchain generates FP-relative memory accesses (st r0,[fp,-8])
for local variables when frame pointers are enabled, which bypasses ARC
hardware stack checking that only monitors SP-based instructions. This
causes the test to fail with MPU violations instead of
stack check violations.

Signed-off-by: Mohamed Moawad <[email protected]>

Author: M-Moawad

tests/kernel/fatal/exception/src/main.c

@@ -415,17 +415,11 @@ ZTEST(fatal_exception, test_fatal)
 
 #ifdef CONFIG_USERSPACE
 
-	/* on arc, this fails with an MPU error instead of a stack
-	 * overflow because the priv stack is merged into the defined
-	 * stack.
-	 */
-#if !defined(CONFIG_ARC)
 	TC_PRINT("test stack HW-based overflow - user 1\n");
 	check_stack_overflow(stack_hw_overflow, K_USER);
 
 	TC_PRINT("test stack HW-based overflow - user 2\n");
 	check_stack_overflow(stack_hw_overflow, K_USER);
-#endif
 
 	TC_PRINT("test stack HW-based overflow - user priv stack 1\n");
 	check_stack_overflow(user_priv_stack_hw_overflow, K_USER);

tests/kernel/fatal/exception/testcase.yaml

@@ -9,6 +9,17 @@ tests:
     filter: CONFIG_ARCH_HAS_STACK_PROTECTION
     arch_exclude:
       - posix
+      - arc
+    tags:
+      - kernel
+      - userspace
+  kernel.common.stack_protection.arc:
+    extra_args: CONF_FILE=prj.conf
+    filter: CONFIG_ARCH_HAS_STACK_PROTECTION
+    arch_allow: arc
+    extra_configs:
+      - CONFIG_OVERRIDE_FRAME_POINTER_DEFAULT=y
+      - CONFIG_OMIT_FRAME_POINTER=y
     tags:
       - kernel
       - userspace