Kernel development is always strange. Andrea Parri recently posted a patch to
change the order of memory reads during multithreaded operation, such that if
one read depended upon the next, the second could not actually occur before the
The problem with this was that the bug never could actually occur, and the fix
made the kernel's behavior less intuitive for developers. Peter
particular, voted nay to this patch, saying it was impossible to construct a
physical system capable of triggering the bug in question.