[$] mseal() and what comes after

Jeff Xu recently proposedthe addition of a new system call, named mseal(), that would allowapplications to prevent modifications to selected memory mappings. Itwould enable the hardening of user-space applications against certain typesof attacks; some other operating systems have this type of feature already.There is support for adding this type of mechanism to the Linux kernel aswell, but it has become clear that mseal() will not land in themainline in anything resembling its current form. Instead, it has becomean example of how not to do kernel development at a number of levels.