summaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
authorLuca Ceresoli <luca.ceresoli@bootlin.com>2026-03-24 09:58:10 +0100
committerLuca Ceresoli <luca.ceresoli@bootlin.com>2026-04-16 09:08:42 +0200
commit6dc294c4d3666525ee80dc6a4c9e123c36ca773c (patch)
treebeb119bbed11a9abc627cc7675064a355a1b6494 /drivers
parentf6d20e06f42ad42e926f94661aebcde78f67ba4d (diff)
drm/bridge: drm_bridge_attach: lock the encoder chain mutex during insertion
drm_bridge_attach() modifies the encoder bridge chain, so take a mutex around such operations to allow users of the chain to protect themselves from chain modifications while iterating. Reviewed-by: Maxime Ripard <mripard@kernel.org> Reviewed-by: Louis Chauvet <louis.chauvet@bootlin.com> Link: https://patch.msgid.link/20260324-drm-bridge-alloc-encoder-chain-mutex-v5-3-8bf786c5c7e6@bootlin.com Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/gpu/drm/drm_bridge.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
index ba80bebb5685..fed8f1f06d94 100644
--- a/drivers/gpu/drm/drm_bridge.c
+++ b/drivers/gpu/drm/drm_bridge.c
@@ -574,10 +574,12 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
bridge->dev = encoder->dev;
bridge->encoder = encoder;
+ mutex_lock(&encoder->bridge_chain_mutex);
if (previous)
list_add(&bridge->chain_node, &previous->chain_node);
else
list_add(&bridge->chain_node, &encoder->bridge_chain);
+ mutex_unlock(&encoder->bridge_chain_mutex);
if (bridge->funcs->attach) {
ret = bridge->funcs->attach(bridge, encoder, flags);
@@ -594,7 +596,9 @@ int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
err_reset_bridge:
bridge->dev = NULL;
bridge->encoder = NULL;
+ mutex_lock(&encoder->bridge_chain_mutex);
list_del(&bridge->chain_node);
+ mutex_unlock(&encoder->bridge_chain_mutex);
if (ret != -EPROBE_DEFER)
DRM_ERROR("failed to attach bridge %pOF to encoder %s: %d\n",