Hi, On 9/7/22 14:46, Tomi Valkeinen wrote:
Hi Maximilian, On 07/09/2022 15:33, Maximilian Luz wrote:Commit f69952a4dc1e ("media: subdev: add active state to struct v4l2_subdev") introduced the active_state member to struct v4l2_subdev. This state needs to be allocated via v4l2_subdev_init_finalize(). The intel-ipu3 driver unfortunately does not do that, due to which,That is fine, a driver only needs to allocate the active state if it uses the active state.active_state is NULL and we run into an oops (NULL pointer dereference) when that state is accessed. In particular, this happens subdev in IOCTLs as commit 3cc7a4bbc381 ("media: subdev: pass also the active state to subdevs from ioctls") passes that state on to the subdev IOCTLs. An example scenario where this happens is running libcamera's qcam or cam on a device with IPU3, for example the Microsoft Surface Book 2. In this case, the oops is reproducibly in v4l2_subdev_get_try_crop(), called via imgu_subdev_set_selection(). To fix this, allocate the active_state member via v4l2_subdev_init_finalize().This is not a correct fix. Sakari has sent (and maybe pushed?) this: https://lore.kernel.org/all/20220825190351.3241444-1-sakari.ailus@xxxxxxxxxxxxxxx/
Thanks! Unfortunately that doesn't fix the issue completely: That patch addresses imgu_subdev_get_selection() but imgu_subdev_set_selection() still runs into the oops. I assume a similar fix to the one you linked is needed? I'll give that a try. Regards, Max
