If the bookkeeping weren't so massive you could cycle through the entire 64-bit address space before re-issuing the same memory address. That would be similar t

If the bookkeeping weren't so massive you could cycle through the entire 64-bit address space before re-issuing the same memory address. That would be similar to a bump allocator; once all the allocations on a page were freed you could unmap it so except for pathological cases you couldn't explode the number of page table entries too horribly. At 1 TB/sec of allocations it would take 500 years to reach the end of the 64-bit address space in the kernel. (It's actually 544 years ignoring leap years and leap seconds, but subtract 44 years for reserved address ranges). The benefit would be making it impossible to use-after-free because the same address would never be re-used.