I have found a solution, maybe the reason is mksquashfs uses all my 4 processors by default, so I add "-processors 1". It runs slower but at least my computer is still awake :).
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/718656 Title: mksquashfs makes Ubuntu shutdown -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs