diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
index fdfaae194ddd..97a77b37daa3 100644
--- a/arch/powerpc/include/asm/processor.h
+++ b/arch/powerpc/include/asm/processor.h
@@ -426,6 +426,8 @@ extern int fix_alignment(struct pt_regs *);
 #endif
 
 int do_mathemu(struct pt_regs *regs);
+int do_spe_mathemu(struct pt_regs *regs);
+int speround_handler(struct pt_regs *regs);
 
 /* VMX copying */
 int enter_vmx_usercopy(void);
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index dadfcef5d6db..dcf4046f8565 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -2103,7 +2103,6 @@ DEFINE_INTERRUPT_HANDLER(CacheLockingException)
 #ifdef CONFIG_SPE
 DEFINE_INTERRUPT_HANDLER(SPEFloatingPointException)
 {
-	extern int do_spe_mathemu(struct pt_regs *regs);
 	unsigned long spefscr;
 	int fpexc_mode;
 	int code = FPE_FLTUNK;
@@ -2153,7 +2152,6 @@ DEFINE_INTERRUPT_HANDLER(SPEFloatingPointException)
 
 DEFINE_INTERRUPT_HANDLER(SPEFloatingPointRoundException)
 {
-	extern int speround_handler(struct pt_regs *regs);
 	int err;
 
 	interrupt_cond_local_irq_enable(regs);
diff --git a/arch/powerpc/math-emu/Makefile b/arch/powerpc/math-emu/Makefile
index 26fef2e5672e..603e59c3db10 100644
--- a/arch/powerpc/math-emu/Makefile
+++ b/arch/powerpc/math-emu/Makefile
@@ -16,3 +16,10 @@ obj-$(CONFIG_SPE)		+= math_efp.o
 
 CFLAGS_fabs.o = -fno-builtin-fabs
 CFLAGS_math.o = -fno-builtin-fabs
+
+ccflags-remove-y = -Wmissing-prototypes -Wmissing-declarations -Wunused-but-set-variable
+
+ifdef KBUILD_EXTRA_WARN
+CFLAGS_math.o += -Wmissing-prototypes -Wmissing-declarations -Wunused-but-set-variable
+CFLAGS_math_efp.o += -Wmissing-prototypes -Wmissing-declarations -Wunused-but-set-variable
+endif
diff --git a/arch/powerpc/math-emu/math_efp.c b/arch/powerpc/math-emu/math_efp.c
index f01e3475f689..34f62aafe706 100644
--- a/arch/powerpc/math-emu/math_efp.c
+++ b/arch/powerpc/math-emu/math_efp.c
@@ -890,7 +890,7 @@ int speround_handler(struct pt_regs *regs)
 	return 0;
 }
 
-int __init spe_mathemu_init(void)
+static int __init spe_mathemu_init(void)
 {
 	u32 pvr, maj, min;