On Thu, 2012-08-02 at 17:41 +0900, Chanho Min wrote: > This patch is to fix a oops from a torn down device. When > scsi_run_queue process starved queues, scsi_request_fn can race with > scsi_remove_device. In this case, rarely, scsi_request_fn release the > last reference and set sdev->request_queue to NULL. It result in > NULL-pointer dereference when spin_unlock is tried with (NULL)-> > queue_lock. We need to add an extra reference to the device on both > sides of the __blk_run_queue to hold reference until scsi_request_fn > is finished. You need a recent kernel with this patch: commit 940f5d47e2f2e1fa00443921a0abf4822335b54d Author: Bart Van Assche <bvanassche@xxxxxxx> Date: Fri Jun 29 15:34:26 2012 +0000 [SCSI] Avoid dangling pointer in scsi_requeue_command() James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html