diff --git a/bootother.S b/bootother.S
index 5e8348e..f243f41 100644
--- a/bootother.S
+++ b/bootother.S
@@ -15,8 +15,8 @@
 #
 # This code is identical to bootasm.S except:
 #   - it does not need to enable A20
-#   - it uses 0(start-4) for the %esp
-#   - it jumps to 0(start-8) instead of calling cmain
+#   - it uses the address at start-4 for the %esp
+#   - it jumps to the address at start-8 instead of calling cmain
 
 .set PROT_MODE_CSEG, 0x8         # kernel code segment selector
 .set PROT_MODE_DSEG, 0x10        # kernel data segment selector
diff --git a/defs.h b/defs.h
index cbacf61..af22433 100644
--- a/defs.h
+++ b/defs.h
@@ -23,7 +23,7 @@ void            kbd_intr(void);
 void            panic(char*) __attribute__((noreturn));
 
 // exec.c
-int            exec(char*, char**);
+int             exec(char*, char**);
 
 // file.c
 struct file*    filealloc(void);
diff --git a/x86.h b/x86.h
index 009fa33..1ef79cb 100644
--- a/x86.h
+++ b/x86.h
@@ -5,6 +5,7 @@ static inline uchar
 inb(ushort port)
 {
   uchar data;
+
   asm volatile("in %1,%0" : "=a" (data) : "d" (port));
   return data;
 }
@@ -91,6 +92,7 @@ static inline void
 cpuid(uint info, uint *eaxp, uint *ebxp, uint *ecxp, uint *edxp)
 {
   uint eax, ebx, ecx, edx;
+
   asm volatile("cpuid" :
                "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx) :
                "a" (info));