diff --git a/arch/alpha/kernel/process.c b/arch/alpha/kernel/process.c
index a8682612abc0..abb739b88ed1 100644
--- a/arch/alpha/kernel/process.c
+++ b/arch/alpha/kernel/process.c
@@ -43,6 +43,11 @@
 #include "proto.h"
 #include "pci_impl.h"
 
+/*
+ * Power off function, if any
+ */
+void (*pm_power_off)(void) = machine_power_off;
+
 void
 cpu_idle(void)
 {
diff --git a/arch/m32r/kernel/process.c b/arch/m32r/kernel/process.c
index cc4b571e5db7..3bf55d92933f 100644
--- a/arch/m32r/kernel/process.c
+++ b/arch/m32r/kernel/process.c
@@ -50,6 +50,10 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
  * Powermanagement idle function, if any..
  */
 void (*pm_idle)(void) = NULL;
+EXPORT_SYMBOL(pm_idle);
+
+void (*pm_power_off)(void) = NULL;
+EXPORT_SYMBOL(pm_power_off);
 
 void disable_hlt(void)
 {
diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c
index a637e885c583..6f1a3a288117 100644
--- a/arch/um/kernel/reboot.c
+++ b/arch/um/kernel/reboot.c
@@ -12,6 +12,8 @@
 #include "mode.h"
 #include "choose-mode.h"
 
+void (*pm_power_off)(void);
+
 #ifdef CONFIG_SMP
 static void kill_idlers(int me)
 {
diff --git a/kernel/sys.c b/kernel/sys.c
index eecf84526afe..d8e49e659027 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -489,6 +489,12 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
 	                magic2 != LINUX_REBOOT_MAGIC2C))
 		return -EINVAL;
 
+	/* Instead of trying to make the power_off code look like
+	 * halt when pm_power_off is not set do it the easy way.
+	 */
+	if ((cmd == LINUX_REBOOT_CMD_POWER_OFF) && !pm_power_off)
+		cmd = LINUX_REBOOT_CMD_HALT;
+
 	lock_kernel();
 	switch (cmd) {
 	case LINUX_REBOOT_CMD_RESTART: