Re: [PATCH v3] kunit: added lockdep support

On Fri, Aug 14, 2020 at 08:55:27PM +0000, Uriel Guajardo wrote:

+void kunit_check_lockdep(struct kunit *test, struct kunit_lockdep *lockdep) {

• int saved_preempt_count = lockdep->preempt_count;
• bool saved_debug_locks = lockdep->debug_locks;
• if (DEBUG_LOCKS_WARN_ON(preempt_count() != saved_preempt_count))

• preempt_count_set(saved_preempt_count);
  

+#ifdef CONFIG_TRACE_IRQFLAGS

• if (softirq_count())

• current->softirqs_enabled = 0;
  

• else

• current->softirqs_enabled = 1;
  

+#endif

This block is pointless. The only way to get softirq tracing out of sync is an unbalanced local_bh_disable(), but then the above preempt_count() test will trigger and kill IRQ tracing.

• if (saved_debug_locks && !debug_locks) {

• kunit_set_failure(test);
  

• kunit_warn(test, "Dynamic analysis tool failure from LOCKDEP.");
  

• kunit_warn(test, "Further tests will have LOCKDEP disabled.");
  

• }

+}