Hello José Expósito,
Commit 600df32dac40 ("drm/vkms: Allow to configure multiple CRTCs")
from Feb 18, 2025 (linux-next), leads to the following Smatch static
checker warning:
drivers/gpu/drm/vkms/tests/vkms_config_test.c:220 vkms_config_test_get_planes()
error: 'plane_cfg1' dereferencing possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:258 vkms_config_test_get_crtcs()
error: 'crtc_cfg2' dereferencing possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:300
vkms_config_test_get_encoders() error: 'encoder_cfg2' dereferencing possible
ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:345
vkms_config_test_get_connectors() error: 'connector_cfg2' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:672
vkms_config_test_plane_attach_crtc() error: 'overlay_cfg' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:674
vkms_config_test_plane_attach_crtc() error: 'primary_cfg' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:676
vkms_config_test_plane_attach_crtc() error: 'cursor_cfg' dereferencing possible
ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:685
vkms_config_test_plane_attach_crtc() error: 'crtc_cfg' dereferencing possible
ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:746
vkms_config_test_plane_get_possible_crtcs() error: 'crtc_cfg1' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:746
vkms_config_test_plane_get_possible_crtcs() error: 'plane_cfg1' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:748
vkms_config_test_plane_get_possible_crtcs() error: 'crtc_cfg2' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:810
vkms_config_test_encoder_get_possible_crtcs() error: 'crtc_cfg1' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:810
vkms_config_test_encoder_get_possible_crtcs() error: 'encoder_cfg1'
dereferencing possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:812
vkms_config_test_encoder_get_possible_crtcs() error: 'crtc_cfg2' dereferencing
possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:876
vkms_config_test_connector_get_possible_encoders() error: 'connector_cfg1'
dereferencing possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:876
vkms_config_test_connector_get_possible_encoders() error: 'encoder_cfg1'
dereferencing possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c:878
vkms_config_test_connector_get_possible_encoders() error: 'encoder_cfg2'
dereferencing possible ERR_PTR()
drivers/gpu/drm/vkms/tests/vkms_config_test.c
231 static void vkms_config_test_get_crtcs(struct kunit *test)
232 {
233 struct vkms_config *config;
234 struct vkms_config_crtc *crtc_cfg;
235 struct vkms_config_crtc *crtc_cfg1, *crtc_cfg2;
236
237 config = vkms_config_create("test");
238 KUNIT_ASSERT_NOT_ERR_OR_NULL(test, config);
239
240 KUNIT_ASSERT_EQ(test, vkms_config_get_num_crtcs(config), 0);
241 vkms_config_for_each_crtc(config, crtc_cfg)
242 KUNIT_FAIL(test, "Unexpected CRTC");
243
244 crtc_cfg1 = vkms_config_create_crtc(config);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
This file has no error checking.
I didn't send an email about it at first because this is just test code so
who cares, but I was recently burned by ignoring errors so now I'm going
through a bunch of old warnings to say that, "Hey, if the author ignores the
error checking that's fine, but I'm in the clear."
245 KUNIT_ASSERT_EQ(test, vkms_config_get_num_crtcs(config), 1);
246 vkms_config_for_each_crtc(config, crtc_cfg) {
247 if (crtc_cfg != crtc_cfg1)
248 KUNIT_FAIL(test, "Unexpected CRTC");
249 }
250
251 crtc_cfg2 = vkms_config_create_crtc(config);
252 KUNIT_ASSERT_EQ(test, vkms_config_get_num_crtcs(config), 2);
253 vkms_config_for_each_crtc(config, crtc_cfg) {
254 if (crtc_cfg != crtc_cfg1 && crtc_cfg != crtc_cfg2)
255 KUNIT_FAIL(test, "Unexpected CRTC");
256 }
257
--> 258 vkms_config_destroy_crtc(config, crtc_cfg2);
259 KUNIT_ASSERT_EQ(test, vkms_config_get_num_crtcs(config), 1);
260 vkms_config_for_each_crtc(config, crtc_cfg) {
261 if (crtc_cfg != crtc_cfg1)
262 KUNIT_FAIL(test, "Unexpected CRTC");
263 }
264
265 vkms_config_destroy(config);
266 }
regards,
dan carpenter
