Re: [PATCH v2 16/19] driver core: Cover trust authorization and binding with KUnit

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] driver core: unskipped driver boot rules in device-trust-full
  KUnit tests
--

commit 8b5fffad66e1e6c0223d2943cea1b5d209f585ac
Author: Leon Romanovsky <leon@kernel.org>

driver core: Cover trust authorization and binding with KUnit

This commit adds KUnit test suites covering device trust policy parsing,
authorization, driver binding, and full-only manual attachment.

> diff --git a/drivers/base/test/device-trust-test.c b/drivers/base/test/device-trust-test.c
> new file mode 100644
> index 0000000000000..b6ad3b0c1b536
> --- /dev/null
> +++ b/drivers/base/test/device-trust-test.c

[ ... ]

> +static void device_trust_full_boot_policy_test(struct kunit *test)
> +{
> +#if IS_BUILTIN(CONFIG_DM_KUNIT_TEST)
> +	struct device_trust_test_context *ctx;
> +	enum device_trust_policy policy;
> +	bool allowed;
> +	int ret;
> +
> +	ctx = device_trust_full_test_register(test, &device_trust_test_plain_bus, NULL);
> +	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
> +	policy = ctx->dev.trust_policy;
> +	allowed = device_trust_test_global_full(test) &&
> +		(policy == DEVICE_TRUST_POLICY_DEFAULT || policy == DEVICE_TRUST_POLICY_FULL) &&
> +		(!device_trust_full_test_driver_rules(test) ||
> +		 ctx->dev.p->trust_policy_override);
> +
> +	ret = device_driver_attach_full(&ctx->drv, &ctx->dev);
> +	KUNIT_ASSERT_EQ(test, ret, allowed ? 0 : -EPERM);
> +	KUNIT_EXPECT_EQ(test, device_is_bound(&ctx->dev), allowed);
> +	KUNIT_EXPECT_EQ(test, ctx->probe_count, allowed ? 1 : 0);
> +	KUNIT_EXPECT_EQ(test, ctx->configure_count, 0);
> +	KUNIT_EXPECT_EQ(test, ctx->dev.trust_policy, policy);
> +	KUNIT_EXPECT_EQ(test, device_get_trust_level(&ctx->dev),
> +			allowed ? DEVICE_TRUST_FULL : DEVICE_TRUST_DISABLED);
> +	KUNIT_EXPECT_EQ(test, device_get_committed_trust_level(&ctx->dev),
> +			allowed ? DEVICE_TRUST_FULL : DEVICE_TRUST_DISABLED);
> +	if (!allowed)
> +		KUNIT_EXPECT_PTR_EQ(test, ctx->dev.driver, NULL);
> +#else
> +	kunit_skip(test, "boot policy coverage requires built-in tests");
> +#endif
> +}
> +
> +static void device_trust_full_attach_test(struct kunit *test)
> +{
> +	struct device_trust_test_context *ctx;
> +	struct device *parent;
> +	int ret;
> +
> +	if (!device_trust_test_global_full(test))
> +		kunit_skip(test, "requires device_trust.default=full");
> +	parent = root_device_register(test->name);
> +	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, parent);
> +	ret = kunit_add_action_or_reset(test,
> +					device_trust_test_parent_unregister, parent);
> +	KUNIT_ASSERT_EQ(test, ret, 0);
> +	ctx = device_trust_full_test_register(test, &device_trust_test_plain_bus, parent);
> +	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
> +
> +	device_lock(parent);
> +	device_lock(&ctx->dev);
> +	ret = device_driver_attach_full(&ctx->drv, &ctx->dev);
> +	device_unlock(&ctx->dev);
> +	device_unlock(parent);
> +	KUNIT_ASSERT_EQ(test, ret, 0);

[ ... ]

> +static void device_trust_full_probe_failure_test(struct kunit *test)
> +{
> +	static const int errors[] = { -EIO, -EPROBE_DEFER };
> +	static const int expected[] = { -EIO, -EAGAIN };
> +	struct device_trust_test_context *ctx;
> +	int i;
> +
> +	if (!device_trust_test_global_full(test))
> +		kunit_skip(test, "requires device_trust.default=full");
> +	ctx = device_trust_full_test_register(test, &device_trust_test_plain_bus, NULL);
> +	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
> +	ctx->drv.probe = device_trust_full_test_probe;
> +
> +	for (i = 0; i < ARRAY_SIZE(errors); i++) {
> +		ctx->probe_ret = errors[i];
> +		KUNIT_ASSERT_EQ(test, device_driver_attach_full(&ctx->drv, &ctx->dev),
> +				expected[i]);

[Severity: Low]
Should device_trust_full_attach_test() and
device_trust_full_probe_failure_test() also skip when device_trust.driver=
boot rules disallow full attachment?

Unlike device_trust_full_boot_policy_test(), both tests only check
device_trust_test_global_full(), which inspects device_trust_init() on a
stub device.  When the kernel is booted with both device_trust.default=full
and a device_trust.driver= rule, device_trust_prepare_full() rejects the
unoverridden test device with -EPERM, causing the device_driver_attach_full()
assertions in both tests to fail instead of skipping.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261109-device-trust-core-v2-0-3b12d9a9f861@nvidia.com?part=16