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Memory Layout

Sinux loads at the traditional 1 MiB mark and manages physical memory above the kernel through a bitmap-based physical memory manager (PMM).

0x000000 - 0x0FFFFF Low memory (BIOS, reserved)
0x100000 Kernel load address (1 MiB)
0x200000 PMM bitmap
[kernel BSS] Page tables, kernel stack (32 KiB)
[above kernel] Free physical pages (PMM managed)
/ ramfs (in RAM, lost on reboot)
/mnt/disk ext2 on ATA drive (persistent)
/proc procfs (kernel info)

Notes

  • The PMM bitmap tracks which physical pages are free or used.
  • The kernel stack is 32 KiB.
  • / is backed by ramfs and is therefore volatile — its contents are lost on reboot.
  • /mnt/disk is backed by ext2 on an ATA drive and provides persistent storage.
  • /proc exposes kernel information via procfs.

See the boot flow for how paging is enabled before the kernel runs.