diff -Naur -X exclude-files ac_cur/arch/um/Makefile-i386 ac/arch/um/Makefile-i386
--- ac_cur/arch/um/Makefile-i386	Sat Sep 15 15:56:11 2001
+++ ac/arch/um/Makefile-i386	Sat Sep 15 20:58:19 2001
@@ -1,3 +1,3 @@
 START_ADDR = 0x10000000
-ARCH_CFLAGS = -U__$(SUBARCH)__ -U$(SUBARCH)
+ARCH_CFLAGS = -U__$(SUBARCH)__ -U$(SUBARCH) -DUM_FASTCALL
 ELF_SUBARCH = $(SUBARCH)
diff -Naur -X exclude-files ac_cur/arch/um/include/sysdep-ppc/sigcontext.h ac/arch/um/include/sysdep-ppc/sigcontext.h
--- ac_cur/arch/um/include/sysdep-ppc/sigcontext.h	Sat Sep 15 15:56:11 2001
+++ ac/arch/um/include/sysdep-ppc/sigcontext.h	Sat Sep 15 20:58:19 2001
@@ -11,6 +11,8 @@
 	struct sigcontext name; \
 	name.regs = &name##_regs
 
+#define DSISR_WRITE 0x02000000
+
 #define SC_FAULT_ADDR(sc) ({ \
 		struct sigcontext_struct *_sc = (sc); \
 		long retval = -1; \
@@ -29,7 +31,23 @@
 		retval; \
 	})
 
-#define SC_FAULT_WRITE(sc) (!!(((sc)->regs->dsisr) & 0x02000000))
+#define SC_FAULT_WRITE(sc) ({ \
+		struct sigcontext_struct *_sc = (sc); \
+		long retval = -1; \
+		switch (_sc->regs->trap) { \
+		case 0x300: \
+			/* data exception */ \
+			retval = !!(_sc->regs->dsisr & DSISR_WRITE); \
+			break; \
+		case 0x400: \
+			/* instruction exception: not a write */ \
+			retval = 0; \
+			break; \
+		default: \
+			panic("SC_FAULT_ADDR: unhandled trap type\n"); \
+		} \
+		retval; \
+	})
 
 #define SC_IP(sc) ((sc)->regs->nip)
 #define SC_SP(sc) ((sc)->regs->gpr[1])
diff -Naur -X exclude-files ac_cur/arch/um/sys-ppc/Makefile ac/arch/um/sys-ppc/Makefile
--- ac_cur/arch/um/sys-ppc/Makefile	Sat Sep 15 16:46:07 2001
+++ ac/arch/um/sys-ppc/Makefile	Sat Sep 15 20:58:19 2001
@@ -14,7 +14,7 @@
 	rm -f $@
 	$(LD) $(LINKFLAGS) --start-group $^ --end-group -o $@
 
-ptrace.o: ptrace.c
+ptrace_user.o: ptrace_user.c
 	$(CC) -D__KERNEL__ $(USER_CFLAGS) $(EXTRA_CFLAGS) -c -o $@ $<
 
 sigcontext.o: sigcontext.c
diff -Naur -X exclude-files ac_cur/arch/um/sys-ppc/sigcontext.c ac/arch/um/sys-ppc/sigcontext.c
--- ac_cur/arch/um/sys-ppc/sigcontext.c	Sat Sep 15 15:56:11 2001
+++ ac/arch/um/sys-ppc/sigcontext.c	Sat Sep 15 20:58:19 2001
@@ -24,8 +24,11 @@
         sc->regs->trap = err;
         sc->regs->dar = cr2;
 #endif
-        *(sc->regs) = *regs;
-        // DAR, DSISR, RESULT?
+	/* This is a bit of a hack; there's some confusion with the
+	 * various definitions of [sys_]pt_regs, and everything isn't
+	 * quite coming together quite right. */
+	memcpy(sc->regs, regs, sizeof(struct sys_pt_regs));
+        /*(sc->regs) = *regs; */
 }
 
 /*
diff -Naur -X exclude-files ac_cur/include/asm-um/processor-ppc.h ac/include/asm-um/processor-ppc.h
--- ac_cur/include/asm-um/processor-ppc.h	Sat Sep 15 15:56:38 2001
+++ ac/include/asm-um/processor-ppc.h	Sat Sep 15 20:58:27 2001
@@ -2,7 +2,11 @@
 #define __UM_PROCESSOR_PPC_H
 
 #if defined(__ASSEMBLY__)
+
 #define CONFIG_ALL_PPC
+#include "arch/processor.h"
+
+#else
 
 #include "asm/processor-generic.h"
 
diff -Naur -X exclude-files ac_cur/include/asm-um/system-ppc.h ac/include/asm-um/system-ppc.h
--- ac_cur/include/asm-um/system-ppc.h	Sat Sep 15 15:56:38 2001
+++ ac/include/asm-um/system-ppc.h	Sat Sep 15 20:58:31 2001
@@ -3,6 +3,12 @@
 
 #define pt_regs sys_pt_regs
 
+#define _switch_to _ppc_switch_to
+
+#include "asm/arch/system.h"
+
+#undef _switch_to
+ 
 #include "asm/system-generic.h"
 
 #undef pt_regs
diff -Naur -X exclude-files ac_cur/include/linux/kernel.h ac/include/linux/kernel.h
--- ac_cur/include/linux/kernel.h	Sat Sep 15 20:48:05 2001
+++ ac/include/linux/kernel.h	Sat Sep 15 21:03:45 2001
@@ -40,7 +40,7 @@
 # define ATTRIB_NORET  __attribute__((noreturn))
 # define NORET_AND     noreturn,
 
-#ifdef __i386__
+#if defined(__i386__) || defined(UM_FASTCALL)
 #define FASTCALL(x)	x __attribute__((regparm(3)))
 #else
 #define FASTCALL(x)	x