diff -upN reference/include/asm-i386/mach-generic/mach_mpspec.h current/include/asm-i386/mach-generic/mach_mpspec.h
--- reference/include/asm-i386/mach-generic/mach_mpspec.h	2003-06-24 16:41:44.000000000 -0700
+++ current/include/asm-i386/mach-generic/mach_mpspec.h	2004-03-31 12:32:15.000000000 -0800
@@ -8,6 +8,8 @@
 
 #define MAX_IRQ_SOURCES 256
 
-#define MAX_MP_BUSSES 32
+/* Summit or generic (i.e. installer) kernels need lots of bus entries. */
+/* Maximum 256 PCI busses, plus 1 ISA bus in each of 4 cabinets. */
+#define MAX_MP_BUSSES 260
 
 #endif /* __ASM_MACH_MPSPEC_H */
diff -upN reference/include/asm-i386/mach-summit/mach_mpspec.h current/include/asm-i386/mach-summit/mach_mpspec.h
--- reference/include/asm-i386/mach-summit/mach_mpspec.h	2003-06-24 16:41:44.000000000 -0700
+++ current/include/asm-i386/mach-summit/mach_mpspec.h	2004-03-31 12:32:15.000000000 -0800
@@ -8,6 +8,7 @@
 
 #define MAX_IRQ_SOURCES 256
 
-#define MAX_MP_BUSSES 32
+/* Maximum 256 PCI busses, plus 1 ISA bus in each of 4 cabinets. */
+#define MAX_MP_BUSSES 260
 
 #endif /* __ASM_MACH_MPSPEC_H */