+extern void enable_sep_cpu(void);
+extern int sysenter_setup(void);
+
+/* Defined in head.S */
+extern struct desc_ptr early_gdt_descr;
+
+extern void cpu_set_gdt(int);
+extern void switch_to_new_gdt(void);
+extern void cpu_init(void);
+extern void init_gdt(int cpu);
+
+/* from system description table in BIOS. Mostly for MCA use, but
+ * others may find it useful. */
+extern unsigned int machine_id;
+extern unsigned int machine_submodel_id;
+extern unsigned int BIOS_revision;
+extern unsigned int mca_pentium_flag;
+