diff options
| author | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2025-10-28 11:15:46 +0100 |
|---|---|---|
| committer | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2025-11-03 13:04:55 +0100 |
| commit | 9347f2fbb0183b04070cd7dfde080bfcc54c0f7c (patch) | |
| tree | 9e69eb6e3d1c048cf2a41f9e753d5cb7e2926eef /drivers/gpu | |
| parent | 76f1a9711b837f90fba91d00e33549ed1364bea2 (diff) | |
drm/bridge: add warning for bridges using neither devm_drm_bridge_alloc() nor drm_bridge_add()
The correct sequence for bridge initialization is:
1. devm_drm_bridge_alloc()
2. drm_bridge_add()
3. drm_bridge_attach()
For bridges missing either 1 or 2 there are warnings in place already,
presenting an explanatory error message.
Bridges missing both 1 and 2 would still face a poorly understandable
message, as reported in a recent regression report [0]:
WARNING: [...] at [...]/lib/refcount.c:25 drm_bridge_attach+0x2c/0x1dc
...
Call trace:
...
drm_bridge_attach
...
Add a new warning to ensure an understandable message is logged in such
cases. Use the same message and warning message already in place in
drm_bridge_add().
[0] https://lore.kernel.org/all/hlf4wdopapxnh4rekl5s3kvoi6egaga3lrjfbx6r223ar3txri@3ik53xw5idyh/
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://patch.msgid.link/20251028-b4-drm-bridge-alloc-add-before-attach-v3-5-bb8611acbbfb@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/drm_bridge.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 6dba601a056b..8f355df883d8 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -441,6 +441,9 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge, if (!encoder || !bridge) return -EINVAL; + if (!bridge->container) + DRM_WARN("DRM bridge corrupted or not allocated by devm_drm_bridge_alloc()\n"); + if (list_empty(&bridge->list)) DRM_WARN("Missing drm_bridge_add() before attach\n"); |