PAGE_MASK is usually found in <asm/page.h>, this just includes an effectively empty <asm-x86_64/page.h>: #ifndef _X86_64_PAGE_H #define _X86_64_PAGE_H #endif /* _X86_64_PAGE_H */
This breaks directfb and pm-utils. :(
Those programs are broken, then. They should not be relying on kernel-private stuff like PAGE_SIZE. Use getpagesize() instead.