On 01/04/2021 14:33, Anirudh Rayabharam wrote: > syzbot has reported the following warning in pvr2_i2c_done: > > sysfs group 'power' not found for kobject '1-0043' > > When the device is disconnected (pvr_hdw_disconnect), the i2c adapter is > not unregistered along with the USB and vl42 teardown. As part of the vl42 -> v4l2 > USB device disconnect, the sysfs files of the subdevices are also > deleted. So, by the time pvr_i2c_core_done is called by > pvr_context_destroy, the sysfs files have been deleted. > > To fix this, unregister the i2c adapter too in pvr_hdw_disconnect. Make > the device deregistration code shared by calling pvr_hdw_disconnect from > pvr2_hdw_destory. destory -> destroy > > Reported-and-tested-by: syzbot+e74a998ca8f1df9cc332@xxxxxxxxxxxxxxxxxxxxxxxxx > Signed-off-by: Anirudh Rayabharam <mail@xxxxxxxxxxxxx> > --- > drivers/media/usb/pvrusb2/pvrusb2-hdw.c | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/drivers/media/usb/pvrusb2/pvrusb2-hdw.c b/drivers/media/usb/pvrusb2/pvrusb2-hdw.c > index f4a727918e35..791227787ff5 100644 > --- a/drivers/media/usb/pvrusb2/pvrusb2-hdw.c > +++ b/drivers/media/usb/pvrusb2/pvrusb2-hdw.c > @@ -2676,9 +2676,7 @@ void pvr2_hdw_destroy(struct pvr2_hdw *hdw) > pvr2_stream_destroy(hdw->vid_stream); > hdw->vid_stream = NULL; > } > - pvr2_i2c_core_done(hdw); > - v4l2_device_unregister(&hdw->v4l2_dev); I think this should still remain since pvr2_hdw_disconnect() doesn't call v4l2_device_unregister(). Can you test that with syzbot? Regards, Hans > - pvr2_hdw_remove_usb_stuff(hdw); > + pvr2_hdw_disconnect(hdw); > mutex_lock(&pvr2_unit_mtx); > do { > if ((hdw->unit_number >= 0) && > @@ -2705,6 +2703,7 @@ void pvr2_hdw_disconnect(struct pvr2_hdw *hdw) > { > pvr2_trace(PVR2_TRACE_INIT,"pvr2_hdw_disconnect(hdw=%p)",hdw); > LOCK_TAKE(hdw->big_lock); > + pvr2_i2c_core_done(hdw); > LOCK_TAKE(hdw->ctl_lock); > pvr2_hdw_remove_usb_stuff(hdw); > LOCK_GIVE(hdw->ctl_lock); >