On 25 August 2025 16.43.06 EEST, Maxime Ripard <mrip...@kernel.org> wrote: >The drm_atomic_get_connector_state() tries to lookup if a connector >state was already allocated in the global state to return early if it >was the case. drm_atomic_get_plane_state() and >drm_atomic_get_crtc_state() behave similarly. > >However, and unlike the other two, drm_atomic_get_connector_state() will >do that lookup after having called drm_modeset_lock(), when the others >will do it before. > >Let's move the early return before the lock to make it consistent. > >Signed-off-by: Maxime Ripard <mrip...@kernel.org> >--- > drivers/gpu/drm/drm_atomic.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > >diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c >index >cd15cf52f0c9144711da5879da57884674aea9e4..fe21f154e0fa030f85fb3d6d35e2684adcf36e26 > 100644 >--- a/drivers/gpu/drm/drm_atomic.c >+++ b/drivers/gpu/drm/drm_atomic.c >@@ -1128,10 +1128,13 @@ drm_atomic_get_connector_state(struct drm_atomic_state >*state, > struct drm_mode_config *config = &connector->dev->mode_config; > struct drm_connector_state *connector_state; > > WARN_ON(!state->acquire_ctx); > >+ if (state->connectors[index].state) >+ return state->connectors[index].state;
Unlike other DRM objects, connectors are dynamic. There is no guarantee that at this point this array entry exists and it's valid. You might be tampering with the unallocated memory. >+ > ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx); > if (ret) > return ERR_PTR(ret); > > index = drm_connector_index(connector); >@@ -1150,13 +1153,10 @@ drm_atomic_get_connector_state(struct drm_atomic_state >*state, > sizeof(*state->connectors) * (alloc - > state->num_connector)); > > state->num_connector = alloc; > } > >- if (state->connectors[index].state) >- return state->connectors[index].state; >- > connector_state = connector->funcs->atomic_duplicate_state(connector); > if (!connector_state) > return ERR_PTR(-ENOMEM); > > drm_connector_get(connector); > With best wishes Dmitry
