Commit f0ad56e8 authored Oct 22, 2018 by Paul E. McKenney

rcu: Eliminate BUG_ON() for kernel/rcu/update.c

The update.c file has a number of calls to BUG_ON(), which panics the
kernel, which is not a good strategy for devices (like embedded) that
don't have a way to capture console output. This commit therefore
converts these BUG_ON() calls to WARN_ON_ONCE() and WARN_ONCE().

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>

parent 9213784b

kernel/rcu/update.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -822,7 +822,8 @@ static int __init rcu_spawn_tasks_kthread(void)
		struct task_struct *t;

		t = kthread_run(rcu_tasks_kthread, NULL, "rcu_tasks_kthread");
		BUG_ON(IS_ERR(t));
		if (WARN_ONCE(IS_ERR(t), "%s: Could not start Tasks-RCU grace-period kthread, OOM is now expected behavior\n", __func__))
		return 0;
		smp_mb(); /* Ensure others see full kthread. */
		WRITE_ONCE(rcu_tasks_kthread_ptr, t);
		return 0;

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