diff options
| author | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2025-09-15 12:12:47 +0200 |
|---|---|---|
| committer | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2025-09-23 22:20:05 +0200 |
| commit | 27312a8f24419b5fe544e30f75d692492790304c (patch) | |
| tree | 151fd0712132e6ed21f353c1526b90bda953f6c8 | |
| parent | 17805a15d1751f5d6bb06f924f9bed216feb8db7 (diff) | |
drm/debugfs: show lingering bridges
The usefulness of /sys/kernel/debug/dri/bridges is limited as it only shows
bridges between drm_bridge_add() and drm_bridge_remove(). However
refcounted bridges can stay allocated and lingering for a long time after
drm_bridge_remove(), and a memory leak due to a missing drm_bridge_put()
would not be visible in this debugfs file.
Add lingering bridges to the /sys/kernel/debug/dri/bridges output.
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://lore.kernel.org/r/20250915-drm-bridge-debugfs-removed-v9-2-6e5c0aff5de9@bootlin.com
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
| -rw-r--r-- | drivers/gpu/drm/drm_bridge.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c index 034dbe7203bf..4d959a34ee46 100644 --- a/drivers/gpu/drm/drm_bridge.c +++ b/drivers/gpu/drm/drm_bridge.c @@ -1447,17 +1447,20 @@ EXPORT_SYMBOL(devm_drm_put_bridge); static void drm_bridge_debugfs_show_bridge(struct drm_printer *p, struct drm_bridge *bridge, - unsigned int idx) + unsigned int idx, + bool lingering) { drm_printf(p, "bridge[%u]: %ps\n", idx, bridge->funcs); - drm_printf(p, "\trefcount: %u\n", kref_read(&bridge->refcount)); + drm_printf(p, "\trefcount: %u%s\n", kref_read(&bridge->refcount), + lingering ? " [lingering]" : ""); drm_printf(p, "\ttype: [%d] %s\n", bridge->type, drm_get_connector_type_name(bridge->type)); - if (bridge->of_node) + /* The OF node could be freed after drm_bridge_remove() */ + if (bridge->of_node && !lingering) drm_printf(p, "\tOF: %pOFfc\n", bridge->of_node); drm_printf(p, "\tops: [0x%x]", bridge->ops); @@ -1483,7 +1486,10 @@ static int allbridges_show(struct seq_file *m, void *data) mutex_lock(&bridge_lock); list_for_each_entry(bridge, &bridge_list, list) - drm_bridge_debugfs_show_bridge(&p, bridge, idx++); + drm_bridge_debugfs_show_bridge(&p, bridge, idx++, false); + + list_for_each_entry(bridge, &bridge_lingering_list, list) + drm_bridge_debugfs_show_bridge(&p, bridge, idx++, true); mutex_unlock(&bridge_lock); @@ -1498,7 +1504,7 @@ static int encoder_bridges_show(struct seq_file *m, void *data) unsigned int idx = 0; drm_for_each_bridge_in_chain_scoped(encoder, bridge) - drm_bridge_debugfs_show_bridge(&p, bridge, idx++); + drm_bridge_debugfs_show_bridge(&p, bridge, idx++, false); return 0; } |