diff --git a/include/asm-um/ptrace-x86_64.h b/include/asm-um/ptrace-x86_64.h
index be51219..c894e68 100644
--- a/include/asm-um/ptrace-x86_64.h
+++ b/include/asm-um/ptrace-x86_64.h
@@ -8,6 +8,8 @@
 #define __UM_PTRACE_X86_64_H
 
 #include "linux/compiler.h"
+#include "asm/errno.h"
+#include "asm/host_ldt.h"
 
 #define signal_fault signal_fault_x86_64
 #define __FRAME_OFFSETS /* Needed to get the R* macros */
@@ -63,15 +65,26 @@
 
 #define profile_pc(regs) PT_REGS_IP(regs)
 
-#endif
+static inline int ptrace_get_thread_area(struct task_struct *child, int idx,
+                                         struct user_desc __user *user_desc)
+{
+        return -ENOSYS;
+}
 
-/*
- * Overrides for Emacs so that we follow Linus's tabbing style.
- * Emacs will notice this stuff at the end of the file and automatically
- * adjust the settings for this buffer only.  This must remain at the end
- * of the file.
- * ---------------------------------------------------------------------------
- * Local variables:
- * c-file-style: "linux"
- * End:
- */
+static inline int ptrace_set_thread_area(struct task_struct *child, int idx,
+                                         struct user_desc __user *user_desc)
+{
+        return -ENOSYS;
+}
+
+static inline void arch_switch_to_tt(struct task_struct *from,
+                                     struct task_struct *to)
+{
+}
+
+static inline void arch_switch_to_skas(struct task_struct *from,
+                                       struct task_struct *to)
+{
+}
+
+#endif