FIXADDR_TOP        61 include/asm-um/fixmap.h #define FIXADDR_TOP	(TASK_SIZE - 2 * PAGE_SIZE)
FIXADDR_TOP       115 include/asm-x86/fixmap_32.h #define FIXADDR_TOP	((unsigned long)__FIXADDR_TOP)
FIXADDR_TOP        75 include/asm-x86/fixmap_64.h #define FIXADDR_TOP	(VSYSCALL_END-PAGE_SIZE)