On 7/6/26 23:00, Gabriele Monaco wrote:
On Tue, 2026-06-16 at 00:44 +0800, [email protected] wrote:
+/*
+ * Test 2: panic notifier chain is reachable.
+ *
+ * vpanic() calls atomic_notifier_call_chain(&panic_notifier_list, ...).
+ * Drive the chain directly to verify panic notifiers receive the
notification —
+ * the observable side-effect of reactor_panic without halting the system.
+ */
+static void test_panic_notifier_called(struct kunit *test)
+{
+ atomic_notifier_chain_register(&panic_notifier_list, &mock_panic_nb);
+ atomic_notifier_call_chain(&panic_notifier_list, 0,
+ "panic violation message");
+ atomic_notifier_chain_unregister(&panic_notifier_list,
&mock_panic_nb);
I just realised this isn't even testing the reactor, it's testing the
notifier_chain thing, I don't think we really need this here or am I missing
something?
Thanks,
Since rv_panic_reaction calls vpanic() which is __noreturn, direct
testing is not feasible in KUnit.
A preparatory v2 drops reactor_printk_kunit.c and reactor_panic_kunit.c
entirely, replacing them with a single rv_reactors_kunit.c containing
two suites:
rv_reactor_registration: register/unregister lifecycle, duplicate
rejection (-EINVAL), name-too-long rejection, and safe unregister
of a never-registered reactor.
rv_react_dispatch: null-callback guard, callback invocation check,
and the mdelay lockdep stress test.
v2 also adds EXPORT_SYMBOL_GPL for rv_react(), rv_register_reactor(),
and rv_unregister_reactor(), and the Kconfig entry is tristate.
Additional fix: rv_unregister_reactor()
Testing exposed a real bug: rv_unregister_reactor() called list_del()
unconditionally. On a never-registered reactor the list_head is
zero-initialised, so list_del() dereferences NULL->prev and crashes.
v2 adds a patch that iterates rv_reactors_list first and only calls
list_del() when the reactor is found. test_unregister_nonexistent
documents and guards this behaviour.
--
Best wishes,
Wen
