shared with the kernel, mapped into kernel address space;
kernel is notified of its location. kernel segment size is
increased to make it fit.
- map in kernel and other processes that don't have their
own page table using single 4MB (global) mapping.
- new sanity check facility: objects that are allocated with
the slab allocator are, when running with sanity checking on,
marked readonly until they are explicitly unlocked using the USE()
macro.
- another sanity check facility: collect all uses of memory and
see if they don't overlap with (a) eachother and (b) free memory
- own munmap() and munmap_text() functions.
- exec() recovers from out-of-memory conditions properly now; this
solves some weird exec() behaviour
- chew off memory from the same side of the chunk as where we
start scanning, solving some memory fragmentation issues
- use avl trees for freelist and phys_ranges in regions
- implement most useful part of munmap()
- remap() stuff is GQ's for shared memory
read/write writable in the pagetable right away instead of waiting for
a pagefault. minor optimization.
some a sanity check of SLAB-allocated pointers.
vm gets its own _exit and __exit like PM, so the stock (library) panic works.
