um: Remove SKAS3/4 support

Before we had SKAS0 UML had two modes of operation
TT (tracing thread) and SKAS3/4 (separated kernel address space).
TT was known to be insecure and got removed a long time ago.
SKAS3/4 required a few (3 or 4) patches on the host side which never went
mainline. The last host patch is 10 years old.

With SKAS0 mode (separated kernel address space using 0 host patches),
default since 2005, SKAS3/4 is obsolete and can be removed.

Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 14 insertions, 21 deletions

diff --git a/arch/um/kernel/reboot.c b/arch/um/kernel/reboot.c
index ced8903..9bdf67a 100644
--- a/arch/um/kernel/reboot.c
+++ b/arch/um/kernel/reboot.c
@@ -15,28 +15,21 @@ void (*pm_power_off)(void);
 
 static void kill_off_processes(void)
 {
-	if (proc_mm)
-		/*
-		 * FIXME: need to loop over userspace_pids
-		 */
-		os_kill_ptraced_process(userspace_pid[0], 1);
-	else {
-		struct task_struct *p;
-		int pid;
-
-		read_lock(&tasklist_lock);
-		for_each_process(p) {
-			struct task_struct *t;
-
-			t = find_lock_task_mm(p);
-			if (!t)
-				continue;
-			pid = t->mm->context.id.u.pid;
-			task_unlock(t);
-			os_kill_ptraced_process(pid, 1);
-		}
-		read_unlock(&tasklist_lock);
+	struct task_struct *p;
+	int pid;
+
+	read_lock(&tasklist_lock);
+	for_each_process(p) {
+		struct task_struct *t;
+
+		t = find_lock_task_mm(p);
+		if (!t)
+			continue;
+		pid = t->mm->context.id.u.pid;
+		task_unlock(t);
+		os_kill_ptraced_process(pid, 1);
 	}
+	read_unlock(&tasklist_lock);
 }
 
 void uml_cleanup(void)