GNU/Fiwix is a 32-bit x86 operating system kernel based on the Unix architecture and fully focused on being Linux compatible. It is designed exclusively for educational purposes, so the kernel code is kept as simple as possible for the benefit of students. In the latest version, the virtual memory manager code has been improved to support SVGAlib-based applications and to add the ability to mmap() physical addresses. The way to map physical addresses in the /dev/mem driver has been improved. The mmap() and readpage() methods have been added to the VFS structure. Among other improvements in the VFS layer, the code to build with gcc 4.x has been fixed.