What's the memory before 0x08048000 used for in 32 bit machine?

Question

In Linux, I learned that every process stores data starting at 0x08048000 in 32 bit machine (and 0x00400000 in 64 bit machine).

But I don\'t know the reason why star

Answer 1

Typical Load Map for x86 for 32 bit Small static app looks like :

 Address     Contents

 0x08048000  code
 0x08052000  data
 0x0805A000  bss (zero data)
 0x08072000  end of data (brk marker)
 0xBFFFE000  stack

All this being in reverse - stack being on top and moving down while data moving up. My guess is the address before 0x08048000 are statically linked something similar to the MBR per OS.