Commit 56b031f0 authored by Marco Elver's avatar Marco Elver Committed by Paul E. McKenney
Browse files

kcsan: Add jiffies test to test suite 



Add a test that KCSAN nor the compiler gets confused about accesses to
jiffies on different architectures.

Signed-off-by: default avatarMarco Elver <elver@google.com>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 7e766560

kernel/kcsan/kcsan-test.c

+23 −0
Original line number Diff line number Diff line
@@ -366,6 +366,11 @@ static noinline void test_kernel_read_struct_zero_size(void) 
	kcsan_check_read(&test_struct.val[3], 0);

}



static noinline void test_kernel_jiffies_reader(void)

{

	sink_value((long)jiffies);

}



static noinline void test_kernel_seqlock_reader(void)

{

	unsigned int seq;
@@ -817,6 +822,23 @@ static void test_assert_exclusive_access_scoped(struct kunit *test) 
	KUNIT_EXPECT_TRUE(test, match_expect_inscope);

}



/*

 * jiffies is special (declared to be volatile) and its accesses are typically

 * not marked; this test ensures that the compiler nor KCSAN gets confused about

 * jiffies's declaration on different architectures.

 */

__no_kcsan

static void test_jiffies_noreport(struct kunit *test)

{

	bool match_never = false;



	begin_test_checks(test_kernel_jiffies_reader, test_kernel_jiffies_reader);

	do {

		match_never = report_available();

	} while (!end_test_checks(match_never));

	KUNIT_EXPECT_FALSE(test, match_never);

}



/* Test that racing accesses in seqlock critical sections are not reported. */

__no_kcsan

static void test_seqlock_noreport(struct kunit *test)
@@ -867,6 +889,7 @@ static struct kunit_case kcsan_test_cases[] = { 
	KCSAN_KUNIT_CASE(test_assert_exclusive_bits_nochange),

	KCSAN_KUNIT_CASE(test_assert_exclusive_writer_scoped),

	KCSAN_KUNIT_CASE(test_assert_exclusive_access_scoped),

	KCSAN_KUNIT_CASE(test_jiffies_noreport),

	KCSAN_KUNIT_CASE(test_seqlock_noreport),

	{},

};