--- ./drivers/char/drm/drmP.h.orig	2004-10-13 03:54:30.000000000 +0000
+++ ./drivers/char/drm/drmP.h	2004-10-15 12:45:48.000000000 +0000
@@ -927,6 +927,7 @@
 
 /* Missing cmpxchg implementation for i386 kernel, copied from old drmP.h -KK Mar 2003 */
 #if __i386__
+#if __missing_cmpxchg__ /* you'd think "#ifndef __cmpxchg" would work, but no */
 static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
                                       unsigned long new, int size)
 {
@@ -957,6 +958,7 @@
 #define cmpxchg(ptr,o,n)                                                \
   ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),              \
                                  (unsigned long)(n),sizeof(*(ptr))))
+#endif /* undefined __cmpxchg */
 #endif /* i386 */
 
 #endif /* __KERNEL__ */