diff --git a/arch/powerpc/include/asm/feature-fixups.h b/arch/powerpc/include/asm/feature-fixups.h
index 96a7d067fbb2..921a8470e18a 100644
--- a/arch/powerpc/include/asm/feature-fixups.h
+++ b/arch/powerpc/include/asm/feature-fixups.h
@@ -37,18 +37,21 @@ label##2:						\
 	.align 2;					\
 label##3:
 
-#define MAKE_FTR_SECTION_ENTRY(msk, val, label, sect)	\
-label##4:						\
-	.popsection;					\
-	.pushsection sect,"a";				\
-	.align 3;					\
-label##5:					       	\
-	FTR_ENTRY_LONG msk;				\
-	FTR_ENTRY_LONG val;				\
-	FTR_ENTRY_OFFSET label##1b-label##5b;		\
-	FTR_ENTRY_OFFSET label##2b-label##5b;	 	\
-	FTR_ENTRY_OFFSET label##3b-label##5b;		\
-	FTR_ENTRY_OFFSET label##4b-label##5b;	 	\
+#define MAKE_FTR_SECTION_ENTRY(msk, val, label, sect)		\
+label##4:							\
+	.popsection;						\
+	.pushsection sect,"a";					\
+	.align 3;						\
+label##5:							\
+	FTR_ENTRY_LONG msk;					\
+	FTR_ENTRY_LONG val;					\
+	FTR_ENTRY_OFFSET label##1b-label##5b;			\
+	FTR_ENTRY_OFFSET label##2b-label##5b;			\
+	FTR_ENTRY_OFFSET label##3b-label##5b;			\
+	FTR_ENTRY_OFFSET label##4b-label##5b;			\
+	.ifgt (label##4b-label##3b)-(label##2b-label##1b);	\
+	.error "Feature section else case larger than body";	\
+	.endif;							\
 	.popsection;
 
 
diff --git a/arch/powerpc/lib/feature-fixups-test.S b/arch/powerpc/lib/feature-fixups-test.S
index cb737484c5aa..f4613118132e 100644
--- a/arch/powerpc/lib/feature-fixups-test.S
+++ b/arch/powerpc/lib/feature-fixups-test.S
@@ -172,6 +172,25 @@ globl(ftr_fixup_test6_expected)
 3:	or	3,3,3
 
 
+#if 0
+/* Test that if we have a larger else case the assembler spots it and
+ * reports an error. #if 0'ed so as not to break the build normally.
+ */
+ftr_fixup_test7:
+	or	1,1,1
+BEGIN_FTR_SECTION
+	or	2,2,2
+	or	2,2,2
+	or	2,2,2
+FTR_SECTION_ELSE
+	or	3,3,3
+	or	3,3,3
+	or	3,3,3
+	or	3,3,3
+ALT_FTR_SECTION_END(0, 1)
+	or	1,1,1
+#endif
+
 #define	MAKE_MACRO_TEST(TYPE)						\
 globl(ftr_fixup_test_ ##TYPE##_macros)					\
 	or	1,1,1;							\