diff options
| author | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2026-03-24 09:58:10 +0100 |
|---|---|---|
| committer | Luca Ceresoli <luca.ceresoli@bootlin.com> | 2026-04-16 09:08:42 +0200 |
| commit | 6dc294c4d3666525ee80dc6a4c9e123c36ca773c (patch) | |
| tree | beb119bbed11a9abc627cc7675064a355a1b6494 | |
| parent | f6d20e06f42ad42e926f94661aebcde78f67ba4d (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>
| -rw-r--r-- | drivers/gpu/drm/drm_bridge.c | 4 |
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", |