The named mode could be invalid and then cmdline parser misses to validate
mode's dimensions, happily adding 0x0 mode as a valid mode. One case where
this happens is NVIDIA Tegra devices that are using downstream bootloader
which adds "video=tegrafb" to the kernel's cmdline and thus upstream Tegra
DRM driver fails to probe because of the invalid mode.
Fixes: 3aeeb13d8996 ("drm/modes: Support modes names on the command line")
Signed-off-by: Dmitry Osipenko <dig...@gmail.com>
---
drivers/gpu/drm/drm_client_modeset.c | 3 ++-
drivers/gpu/drm/drm_modes.c | 6 ++++++
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/drm_client_modeset.c
b/drivers/gpu/drm/drm_client_modeset.c
index e95fceac8f8b..56d36779d213 100644
--- a/drivers/gpu/drm/drm_client_modeset.c
+++ b/drivers/gpu/drm/drm_client_modeset.c
@@ -180,7 +180,8 @@ drm_connector_pick_cmdline_mode(struct drm_connector
*connector)
create_mode:
mode = drm_mode_create_from_cmdline_mode(connector->dev, cmdline_mode);
- list_add(&mode->head, &connector->modes);
+ if (mode)
+ list_add(&mode->head, &connector->modes);
return mode;
}
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 910561d4f071..74a5739df506 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -158,6 +158,9 @@ struct drm_display_mode *drm_cvt_mode(struct drm_device
*dev, int hdisplay,
int interlace;
u64 tmp;
+ if (!hdisplay || !vdisplay)
+ return NULL;
+
/* allocate the drm_display_mode structure. If failure, we will
* return directly
*/
@@ -392,6 +395,9 @@ drm_gtf_mode_complex(struct drm_device *dev, int hdisplay,
int vdisplay,
int hsync, hfront_porch, vodd_front_porch_lines;
unsigned int tmp1, tmp2;
+ if (!hdisplay || !vdisplay)
+ return NULL;
+
drm_mode = drm_mode_create(dev);
if (!drm_mode)
return NULL;
--
2.22.0
