arm: bugfix: save_boot_params_default accesses uninitalized stack when -O0

save_boot_params_default() in cpu.c accesses uninitialized stack area when it compiled with -O0 (not optimized).

Signed-off-by Tetsuyuki Kobayashi<[email protected]>

---
Changes for v2:
- include<linux/compiler.h> and use __naked instead of __attribute__((naked))

  arch/arm/cpu/armv7/cpu.c |    4 ++++
  1 file changed, 4 insertions(+)

arch/arm/cpu/armv7/cpu.c +4 -0

index c6fa8ef..3e2a75c 100644
@@ -36,9 +36,13 @@
  #include<asm/system.h>
  #include<asm/cache.h>
  #include<asm/armv7.h>
+#include<linux/compiler.h>
 
+__naked /* don't save anything to stack even if compiled with -O0 */
  void save_boot_params_default(u32 r0, u32 r1, u32 r2, u32 r3)
  {
+	/* stack is not yet initialized */
+	asm("bx lr");
  }
 
  void save_boot_params(u32 r0, u32 r1, u32 r2, u32 r3)