Hi Alice, > Device reset thread uses kobject_uevent_env() to get kobj.parent > after scsi_evt_emit(), and it races with device init thread which > calls device_add() to create kobj.parent before kobject_uevent_env(). > > Device reset call trace: > fill_kobj_path > kobject_get_path > kobject_uevent_env > scsi_evt_emit <- add wait_event() > scsi_evt_thread > > Device init call trace: > fill_kobj_path > kobject_get_path > kobject_uevent_env > device_add <- create kobj.parent > scsi_target_add > scsi_sysfs_add_sdev > scsi_add_lun > scsi_probe_and_add_lun > > These two jobs are scheduled asynchronously, we can't guaranteed that > kobj.parent will be created in device init thread before device reset > thread calls kobj_get_path(). > > To resolve the racing issue between device init thread and device > reset thread, we use wait_event() in scsi_evt_emit() to wait for > device_add() to complete the creation of kobj.parent. > > Signed-off-by: Alice Chao <alice.chao@xxxxxxxxxxxx> > Change-Id: I2848cf054186739d3a125a0635dbed5539557e64 please remove Change-Id here thanks, Miles
