search for: drm_dp_port_setup_pdt

...4:45:54PM -0400, Lyude Paul wrote: > Since we're going to be implementing suspend/resume reprobing very soon, > we need to make sure we are extra careful to ensure that our locking > actually protects the topology state where we expect it to. Turns out > this isn't the case with drm_dp_port_setup_pdt() and > drm_dp_port_teardown_pdt(), both of which change port->mstb without > grabbing &mgr->lock. > > Additionally, since most callers of these functions are just using it to > teardown the port's previous PDT and setup a new one we can simplify > things a bit and...

Since we're going to be implementing suspend/resume reprobing very soon, we need to make sure we are extra careful to ensure that our locking actually protects the topology state where we expect it to. Turns out this isn't the case with drm_dp_port_setup_pdt() and drm_dp_port_teardown_pdt(), both of which change port->mstb without grabbing &mgr->lock. Additionally, since most callers of these functions are just using it to teardown the port's previous PDT and setup a new one we can simplify things a bit and combine drm_dp_port_setup_pdt(...

Since we're going to be implementing suspend/resume reprobing very soon, we need to make sure we are extra careful to ensure that our locking actually protects the topology state where we expect it to. Turns out this isn't the case with drm_dp_port_setup_pdt() and drm_dp_port_teardown_pdt(), both of which change port->mstb without grabbing &mgr->lock. Additionally, since most callers of these functions are just using it to teardown the port's previous PDT and setup a new one we can simplify things a bit and combine drm_dp_port_setup_pdt(...

...de Paul wrote: > > Since we're going to be implementing suspend/resume reprobing very soon, > > we need to make sure we are extra careful to ensure that our locking > > actually protects the topology state where we expect it to. Turns out > > this isn't the case with drm_dp_port_setup_pdt() and > > drm_dp_port_teardown_pdt(), both of which change port->mstb without > > grabbing &mgr->lock. > > > > Additionally, since most callers of these functions are just using it to > > teardown the port's previous PDT and setup a new one we can simpli...

This is the large series for adding MST suspend/resume reprobing that I've been working on for quite a while now. In addition, I: - Refactored and cleaned up any code I ended up digging through in the process of understanding how some parts of these helpers worked. - Added some debugging tools along the way that I ended up needing to figure out some issues in my own code Note that

This is the final portion of the large series for adding MST suspend/resume reprobing that I've been working on for quite a while now. In addition, I: * Refactored and cleaned up any code I ended up digging through in the process of understanding how some parts of these helpers worked. * Added some debugging tools along the way that I ended up needing to figure out some issues in my own

..._port *port; + int ret; list_for_each_entry(port, &mstb->ports, next) { if (port->port_num == port_num) { - kref_get(&port->kref); - return port; + ret = drm_dp_mst_topology_try_get_port(port); + return ret ? port : NULL; } } @@ -1095,6 +1410,11 @@ static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) if (port->mstb) { port->mstb->mgr = port->mgr; port->mstb->port_parent = port; + /* + * Make sure this port's memory allocation stays + * around until it's child MSTB releases it + */ + drm_dp_mst_get_port_malloc(port);...

..._port *port; + int ret; list_for_each_entry(port, &mstb->ports, next) { if (port->port_num == port_num) { - kref_get(&port->kref); - return port; + ret = drm_dp_mst_topology_try_get_port(port); + return ret ? port : NULL; } } @@ -1095,6 +1410,11 @@ static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) if (port->mstb) { port->mstb->mgr = port->mgr; port->mstb->port_parent = port; + /* + * Make sure this port's memory allocation stays + * around until it's child MSTB releases it + */ + drm_dp_mst_get_port_malloc(port);...

..._mst_port *port; + int ret; list_for_each_entry(port, &mstb->ports, next) { if (port->port_num == port_num) { - kref_get(&port->kref); - return port; + ret = drm_dp_mst_topology_get_port(port); + return ret ? port : NULL; } } @@ -1087,6 +1316,11 @@ static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) if (port->mstb) { port->mstb->mgr = port->mgr; port->mstb->port_parent = port; + /* + * Make sure this port's memory allocation stays + * around until it's child MSTB releases it + */ + drm_dp_mst_get_port_malloc(port);...

..._entry(port, &mstb->ports, next) { > if (port->port_num == port_num) { > - kref_get(&port->kref); > - return port; > + ret = drm_dp_mst_topology_get_port(port); > + return ret ? port : NULL; > } > } > > @@ -1087,6 +1316,11 @@ static bool drm_dp_port_setup_pdt(struct drm_dp_mst_port *port) > if (port->mstb) { > port->mstb->mgr = port->mgr; > port->mstb->port_parent = port; > + /* > + * Make sure this port's memory allocation stays > + * around until it's child MSTB releases it > + */ &g...

...num) { > > > - kref_get(&port->kref); > > > - return port; > > > + ret = drm_dp_mst_topology_get_port(port); > > > + return ret ? port : NULL; > > > } > > > } > > > > > > @@ -1087,6 +1316,11 @@ static bool drm_dp_port_setup_pdt(struct > > > drm_dp_mst_port *port) > > > if (port->mstb) { > > > port->mstb->mgr = port->mgr; > > > port->mstb->port_parent = port; > > > + /* > > > + * Make sure this port's memory allocation stays > &g...

...; > if (port->port_num == port_num) { > > - kref_get(&port->kref); > > - return port; > > + ret = drm_dp_mst_topology_get_port(port); > > + return ret ? port : NULL; > > } > > } > > > > @@ -1087,6 +1316,11 @@ static bool drm_dp_port_setup_pdt(struct > > drm_dp_mst_port *port) > > if (port->mstb) { > > port->mstb->mgr = port->mgr; > > port->mstb->port_parent = port; > > + /* > > + * Make sure this port's memory allocation stays > > + * around until it'...

This is the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream implementation requires a

This is a WIP version of the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream

This is the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream implementation requires a

This is the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream implementation requires a

This is the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream implementation requires a

This is the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream implementation requires a

This is the series I've been working on for a while now to get all of the atomic DRM drivers in the tree to use the atomic MST helpers, and to make the atomic MST helpers actually idempotent. Turns out it's a lot more difficult to do that without also fixing how port and branch device refcounting works so that it actually makes sense, since the current upstream implementation requires a