Hi, On 18/11/2025 14:40, Maxime Ripard wrote: > Hi, > > On Tue, Nov 18, 2025 at 05:22:49PM +0530, Harikrishna Shenoy wrote: >> With the DBANC framework, the connector is no longer initialized in >> bridge_attach() when the display controller sets the >> DRM_BRIDGE_ATTACH_NO_CONNECTOR flag. >> This causes a null pointer dereference in cdns_mhdp_modeset_retry_fn() >> when trying to access &conn->dev->mode_config.mutex. >> Observed on a board where EDID read failed. >> (log: https://gist.github.com/Jayesh2000/233f87f9becdf1e66f1da6fd53f77429) >> >> Patch 1 adds a connector_ptr which takes care of both >> DBANC and !DBANC case by setting the pointer in appropriate hooks >> and checking for pointer validity before accessing the connector. >> Patch 2 adds mode validation hook to bridge fucntions. >> Patch 3 fixes HDCP to work with both DBANC and !DBANC case by >> moving HDCP state handling into the bridge atomic check in line with >> the DBANC model. >> Patches 4,5 do necessary cleanup and alignment for using >> connector pointer. > > It's mentioned several times in your series, and it might be obvious to > you, but documenting what is the "DBANC framework" is would be helpful. > I have no idea what it's about, and it appears that Google doesn't know > either. Yes, I was a bit baffled initially. DRM_BRIDGE_ATTACH_NO_CONNECTOR.
I think it makes sense to only use "DBANC" if it's first introduced in that patch. So don't have a patch that just uses "DBANC", even if the previous patch did explain what it means. And if there's just one or two "DBANC"s, just spell it out "DRM_BRIDGE_ATTACH_NO_CONNECTOR". Tomi
