The scheduler apparently now requires this.
diff -ruN -X../cludes linux-2.5.66-moo.orig/arch/v850/kernel/entry.S linux-2.5.66-moo/arch/v850/kernel/entry.S
--- linux-2.5.66-moo.orig/arch/v850/kernel/entry.S 2003-02-25 10:44:59.000000000 +0900
+++ linux-2.5.66-moo/arch/v850/kernel/entry.S 2003-03-25 10:37:52.000000000 +0900
@@ -511,10 +511,8 @@
(copy_thread makes ret_from_fork the return address in each new thread's
saved context). */
C_ENTRY(ret_from_fork):
-#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
mov r10, r6 // switch_thread returns the prev task.
jarl CSYM(schedule_tail), lp // ...which is schedule_tail's arg
-#endif
mov r0, r10 // Child's fork call should return 0.
br ret_from_trap // Do normal trap return.
C_END(ret_from_fork)