On Fri, Jun 18, 2021 at 10:35:21AM -0400, Jason J. Herne wrote: > On 6/18/21 10:10 AM, Jason Gunthorpe wrote: > > On Fri, Jun 18, 2021 at 09:35:24AM -0400, Jason J. Herne wrote: > > > vfio_ap_matrix_dev_release is shadowing the global matrix_dev with driver > > > data that never gets set. So when release is called we end up not freeing > > > matrix_dev. The fix is to remove the shadow variable and just free the > > > global. > > > > I would clarify this commit message to say that the drv_data of the > > matrix_dev is never set and so dev_get_drvdata() always returns NULL > > > > And I would suggest to use > > > > container_of(dev, struct ap_matrix_dev, dev) > > > > instead of the global variable, and probably NULL the global > > too.. > > > > The use of driver_data seems to have been completely erroneous here. In this > case the global matrix_dev is the top level struct. It is not contained in > anything. matrix_dev is created upon module load, and it is freed when the > module exits. > > So I don't think using container_of makes sense. Unless I've > misunderstood your suggestion? matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL); matrix_dev->device.release = vfio_ap_matrix_dev_release; ret = device_register(&matrix_dev->device); "dev" is contained inside matrix_dev which is why we should use container of to go from a struct device pointer back to the containing matrix_dev pointer Jason
