My old stuff

Signed-off-by: Calvin Leung Huang <cleung2010@gmail.com>
Merge branch 'master' of https://github.com/cleung2010/os_pj1
My old stuff

Signed-off-by: Calvin Leung Huang <cleung2010@gmail.com>
Merge branch 'master' of https://github.com/cleung2010/os_pj1