Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-07-14

The following pull-request contains BPF updates for your *net-next* tree.

We've added 21 non-merge commits during the last 1 day(s) which contain
a total of 20 files changed, 308 insertions(+), 279 deletions(-).

The main changes are:

1) Fix selftests/bpf build, from Alexei.

2) Fix resolve_btfids build issues, from Jiri.

3) Pull usermode-driver-cleanup set, from Eric.

4) Two minor fixes to bpfilter, from Alexei and Masahiro.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 1 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 727150f28103..39226a018ed7 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -804,7 +804,6 @@ void __noreturn do_exit(long code)
 	exit_task_namespaces(tsk);
 	exit_task_work(tsk);
 	exit_thread(tsk);
-	exit_umh(tsk);
 
 	/*
 	 * Flush inherited counters to the parent - before the parent
@@ -1711,6 +1710,30 @@ Efault:
 }
 #endif
 
+/**
+ * thread_group_exited - check that a thread group has exited
+ * @pid: tgid of thread group to be checked.
+ *
+ * Test if the thread group represented by tgid has exited (all
+ * threads are zombies, dead or completely gone).
+ *
+ * Return: true if the thread group has exited. false otherwise.
+ */
+bool thread_group_exited(struct pid *pid)
+{
+	struct task_struct *task;
+	bool exited;
+
+	rcu_read_lock();
+	task = pid_task(pid, PIDTYPE_PID);
+	exited = !task ||
+		(READ_ONCE(task->exit_state) && thread_group_empty(task));
+	rcu_read_unlock();
+
+	return exited;
+}
+EXPORT_SYMBOL(thread_group_exited);
+
 __weak void abort(void)
 {
 	BUG();