This is just a virtual number that the guest can query through the
various means. Will affect mesa with how many helper threads it
generates at the very least
4GB virtual memory is too small and causes things to fault.
Previously we were at `1 << 36` but it caused oom issues on devices with
smaller amounts of memory.
This time ensure the the SHM memory is allocated with MEM_NORESERVE so
devices can actually allocate the virtual memory region.
We need to reserve that space for EXEC apps and 32bit apps. Hard throw a
warning if any of our mapping space ends up in the lower 32bits.
PIE and potentially a custom dynamic linker can enforce this.
Ryan Houdek