Commit bdff746a authored Feb 04, 2008 by Andrew Morton Committed by Linus Torvalds Feb 05, 2008

clone: prepare to recycle CLONE_STOPPED



Ulrich says that we never used this clone flags and that nothing should be
using it.

As we're down to only a single bit left in clone's flags argument, let's add a
warning to check that no userspace is actually using it.  Hopefully we will
be able to recycle it.

Roland said:

  CLONE_STOPPED was previously used by some NTPL versions when under
  thread_db (i.e.  only when being actively debugged by gdb), but not for a
  long time now, and it never worked reliably when it was used.  Removing it
  seems fine to me.

[akpm@linux-foundation.org: it looks like CLONE_DETACHED is being used]
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 59714d65

kernel/fork.c

+17 −0

Original line number	Diff line number	Diff line
		@@ -1450,6 +1450,23 @@ long do_fork(unsigned long clone_flags,
		int trace = 0;
		long nr;

		/*
		* We hope to recycle these flags after 2.6.26
		*/
		if (unlikely(clone_flags & CLONE_STOPPED)) {
		static int __read_mostly count = 100;

		if (count > 0 && printk_ratelimit()) {
		char comm[TASK_COMM_LEN];

		count--;
		printk(KERN_INFO "fork(): process `%s' used deprecated "
		"clone flags 0x%lx\n",
		get_task_comm(comm, current),
		clone_flags & CLONE_STOPPED);
		}
		}

		if (unlikely(current->ptrace)) {
		trace = fork_traceflag (clone_flags);
		if (trace)