diff --git a/doc/mach.texi b/doc/mach.texi
index 9ad9e70..d089224 100644
--- a/doc/mach.texi
+++ b/doc/mach.texi
@@ -5037,6 +5037,17 @@ total system run time for live threads
 This is a pointer to a @code{struct task_thread_times_info}.
 @end deftp
 
+@deftypefun kern_return_t task_set_name (@w{task_t @var{target_task}}, @w{kernel_debug_name_t @var{name}})
+
+The function @code{task_set_name} sets the name of @var{target_task}
+to @var{name}, truncating it if necessary.
+
+This is a debugging aid.  The name is used in diagnostic messages
+printed by the kernel.
+
+The function returns @code{KERN_SUCCESS} if the call succeeded.
+@end deftypefun
+
 
 @node Task Execution
 @subsection Task Execution
diff --git a/include/mach/gnumach.defs b/include/mach/gnumach.defs
index 12c4e99..6cfbb0d 100644
--- a/include/mach/gnumach.defs
+++ b/include/mach/gnumach.defs
@@ -27,6 +27,7 @@ subsystem
 
 #include <mach/std_types.defs>
 #include <mach/mach_types.defs>
+#include <mach_debug/mach_debug_types.defs>
 
 type vm_cache_statistics_data_t = struct[11] of integer_t;
 
@@ -63,3 +64,11 @@ simpleroutine thread_terminate_release(
 		reply_port	: mach_port_name_t;
 		address		: vm_address_t;
 		size		: vm_size_t);
+
+/*
+ *	Set the name of task TASK to NAME.  This is a debugging aid.
+ *	NAME will be used in error messages printed by the kernel.
+ */
+simpleroutine task_set_name(
+		task	: task_t;
+		name	: kernel_debug_name_t);
diff --git a/kern/task.c b/kern/task.c
index 0b5a6f7..66eb25c 100644
--- a/kern/task.c
+++ b/kern/task.c
@@ -37,6 +37,7 @@
 #include <mach/vm_param.h>
 #include <mach/task_info.h>
 #include <mach/task_special_ports.h>
+#include <mach_debug/mach_debug_types.h>
 #include <ipc/ipc_space.h>
 #include <ipc/ipc_types.h>
 #include <kern/debug.h>
@@ -1071,6 +1072,22 @@ task_priority(
 }
 
 /*
+ *	task_set_name
+ *
+ *	Set the name of task TASK to NAME.  This is a debugging aid.
+ *	NAME will be used in error messages printed by the kernel.
+ */
+kern_return_t
+task_set_name(
+	task_t			task,
+	kernel_debug_name_t	name)
+{
+	strncpy(task->name, name, sizeof task->name - 1);
+	task->name[sizeof task->name - 1] = '\0';
+	return KERN_SUCCESS;
+}
+
+/*
  *	task_collect_scan:
  *
  *	Attempt to free resources owned by tasks.
diff --git a/kern/task.h b/kern/task.h
index 7ae10cd..3c10dc0 100644
--- a/kern/task.h
+++ b/kern/task.h
@@ -39,6 +39,7 @@
 #include <mach/time_value.h>
 #include <mach/mach_param.h>
 #include <mach/task_info.h>
+#include <mach_debug/mach_debug_types.h>
 #include <kern/kern_types.h>
 #include <kern/lock.h>
 #include <kern/queue.h>
@@ -169,6 +170,9 @@ extern kern_return_t	task_assign(
 extern kern_return_t	task_assign_default(
 	task_t		task,
 	boolean_t	assign_threads);
+extern kern_return_t	task_set_name(
+	task_t			task,
+	kernel_debug_name_t	name);
 extern void consider_task_collect(void);
 
 /*