diff --git a/drivers/staging/lustre/lustre/llite/statahead.c b/drivers/staging/lustre/lustre/llite/statahead.c
index c8624b5a9875..74d95b04d235 100644
--- a/drivers/staging/lustre/lustre/llite/statahead.c
+++ b/drivers/staging/lustre/lustre/llite/statahead.c
@@ -964,7 +964,11 @@ static int ll_agl_thread(void *arg)
 	atomic_inc(&sbi->ll_agl_total);
 	spin_lock(&plli->lli_agl_lock);
 	sai->sai_agl_valid = 1;
-	thread_set_flags(thread, SVC_RUNNING);
+	if (thread_is_init(thread))
+		/* If someone else has changed the thread state
+		 * (e.g. already changed to SVC_STOPPING), we can't just
+		 * blindly overwrite that setting. */
+		thread_set_flags(thread, SVC_RUNNING);
 	spin_unlock(&plli->lli_agl_lock);
 	wake_up(&thread->t_ctl_waitq);
 
@@ -1058,7 +1062,11 @@ static int ll_statahead_thread(void *arg)
 
 	atomic_inc(&sbi->ll_sa_total);
 	spin_lock(&plli->lli_sa_lock);
-	thread_set_flags(thread, SVC_RUNNING);
+	if (thread_is_init(thread))
+		/* If someone else has changed the thread state
+		 * (e.g. already changed to SVC_STOPPING), we can't just
+		 * blindly overwrite that setting. */
+		thread_set_flags(thread, SVC_RUNNING);
 	spin_unlock(&plli->lli_sa_lock);
 	wake_up(&thread->t_ctl_waitq);
 
@@ -1658,6 +1666,12 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
 	CDEBUG(D_READA, "start statahead thread: [pid %d] [parent %.*s]\n",
 	       current_pid(), parent->d_name.len, parent->d_name.name);
 
+	/* The sai buffer already has one reference taken at allocation time,
+	 * but as soon as we expose the sai by attaching it to the lli that
+	 * default reference can be dropped by another thread calling
+	 * ll_stop_statahead. We need to take a local reference to protect
+	 * the sai buffer while we intend to access it. */
+	ll_sai_get(sai);
 	lli->lli_sai = sai;
 
 	plli = ll_i2info(parent->d_inode);
@@ -1670,6 +1684,9 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
 		lli->lli_opendir_key = NULL;
 		thread_set_flags(thread, SVC_STOPPED);
 		thread_set_flags(&sai->sai_agl_thread, SVC_STOPPED);
+		/* Drop both our own local reference and the default
+		 * reference from allocation time. */
+		ll_sai_put(sai);
 		ll_sai_put(sai);
 		LASSERT(lli->lli_sai == NULL);
 		return -EAGAIN;
@@ -1678,6 +1695,7 @@ int do_statahead_enter(struct inode *dir, struct dentry **dentryp,
 	l_wait_event(thread->t_ctl_waitq,
 		     thread_is_running(thread) || thread_is_stopped(thread),
 		     &lwi);
+	ll_sai_put(sai);
 
 	/*
 	 * We don't stat-ahead for the first dirent since we are already in