Merge 7.2-rc3 into tty-next

We need the tty/serial fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 6 insertions, 1 deletions

diff --git a/kernel/exit.c b/kernel/exit.c
index 1056422bc101..2c0b1c02920f 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -212,7 +212,12 @@ static void __exit_signal(struct release_task_post *post, struct task_struct *ts
 	__unhash_process(post, tsk, group_dead);
 	write_sequnlock(&sig->stats_lock);
 
-	tsk->sighand = NULL;
+	/*
+	 * Ensure that all preceeding state is visible. Pairs with
+	 * the smp_acquire__after_ctrl_dep() in the sighand == NULL
+	 * path of lock_task_sighand().
+	 */
+	smp_store_release(&tsk->sighand, NULL);
 	spin_unlock(&sighand->siglock);
 
 	__cleanup_sighand(sighand);