[PATCH] Remove CLONE_DETACHED

From: Andries.Brouwer@cwi.nl

Remove obsolete CLONE_DETACHED

include/linux/sched.h

@@ -50,7 +50,7 @@ struct exec_domain;
 #define CLONE_SETTLS	0x00080000	/* create a new TLS for the child */
 #define CLONE_PARENT_SETTID	0x00100000	/* set the TID in the parent */
 #define CLONE_CHILD_CLEARTID	0x00200000	/* clear the TID in the child */
-#define CLONE_DETACHED		0x00400000	/* Not used - CLONE_THREAD implies detached uniquely */
+#define CLONE_DETACHED		0x00400000	/* Unused, ignored */
 #define CLONE_UNTRACED		0x00800000	/* set if the tracing process can't force CLONE_PTRACE on this clone */
 #define CLONE_CHILD_SETTID	0x01000000	/* set the TID in the child */
 #define CLONE_STOPPED		0x02000000	/* Start in stopped state */

kernel/fork.c

@@ -859,22 +859,6 @@ struct task_struct *copy_process(unsigned long clone_flags,
 	if ((clone_flags & CLONE_SIGHAND) && !(clone_flags & CLONE_VM))
 		return ERR_PTR(-EINVAL);
 
-	/*
-	 * CLONE_DETACHED must match CLONE_THREAD: it's a historical
-	 * thing.
-	 */
-	if (!(clone_flags & CLONE_DETACHED) != !(clone_flags & CLONE_THREAD)) {
-		/* Warn about the old no longer supported case so that we see it */
-		if (clone_flags & CLONE_THREAD) {
-			static int count;
-			if (count < 5) {
-				count++;
-				printk(KERN_WARNING "%s trying to use CLONE_THREAD without CLONE_DETACH\n", current->comm);
-			}
-		}
-		return ERR_PTR(-EINVAL);
-	}
-
 	retval = security_task_create(clone_flags);
 	if (retval)
 		goto fork_out;