diff --git a/kernel/trunk/detect/getcache.inc b/kernel/trunk/detect/getcache.inc
index 08a79b7488..bd5da5f8c9 100644
--- a/kernel/trunk/detect/getcache.inc
+++ b/kernel/trunk/detect/getcache.inc
@@ -358,6 +358,7 @@ calculate_for_hd:
     shl  ebx,9
     pop  eax
     sub  eax,ebx
+    dec  ecx
     ret
 
 calculate_for_cd:
@@ -371,6 +372,7 @@ calculate_for_cd:
     shl  ebx,11
     pop  eax
     sub  eax,ebx
+    dec  ecx
     ret
     
 clear_ide_cache: