rcu: Protect rcu_check_gp_kthread_starvation() access to ->gp_flags



The rcu_check_gp_kthread_starvation() function can be invoked without
holding locks, so the access to the rcu_state structure's ->gp_flags
field must be protected with READ_ONCE().  This commit therefore adds
this protection.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

parent fd897573

kernel/rcu/tree.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1192,7 +1192,7 @@ static void rcu_check_gp_kthread_starvation(void)
		pr_err("%s kthread starved for %ld jiffies! g%ld f%#x %s(%d) ->state=%#lx ->cpu=%d\n",
		rcu_state.name, j,
		(long)rcu_seq_current(&rcu_state.gp_seq),
		rcu_state.gp_flags,
		READ_ONCE(rcu_state.gp_flags),
		gp_state_getname(rcu_state.gp_state), rcu_state.gp_state,
		gpk ? gpk->state : ~0, gpk ? task_cpu(gpk) : -1);
		if (gpk) {