Regarding the compilation warning reported above: "sparse: shift too big (64) for type unsigned long" at line 639 "sparse: invalid access past the end of 'old' (8 8)" at line 638 Kindly refer to the code above, at these line numbers. I am in the process of fixing this warning. But what would be the fix? ? At the moment can't think of a code-fix to make the compilation warning disappear (specially at line 639). Can anyone please explain to me the meaning of the compilation warning more deeply?