“Theodore Ts’o proposed a new patch allowing a userland program
to taint the kernel by writing to
/proc/sys/kernel/tainted, ‘to be used when userspace
is potentially doing something naughty that might compromise the
kernel.’ When asked when this would be needed, Theodore went on to
explain, ‘the problem is that the Real-Time Specification for Java
(RTSJ) **requires** that the JVM provide class functions which
provide direct access to physical memory; all physical memory. In
fact, the RTSJ compliance test explicitly checks for this; it
requires that you give the compliance test the address of a few
hundred megs of physical memory for the test…'”