diff --git a/drivers/accel/qaic/qaic_control.c b/drivers/accel/qaic/qaic_control.c index f698d5dfd326..43f84d438960 100644 --- a/drivers/accel/qaic/qaic_control.c +++ b/drivers/accel/qaic/qaic_control.c @@ -914,7 +914,7 @@ static int decode_deactivate(struct qaic_device *qdev, void *trans, u32 *msg_len */ return -ENODEV; - if (status) { + if (usr && status) { /* * Releasing resources failed on the device side, which puts * us in a bind since they may still be in use, so enable the @@ -1109,6 +1109,9 @@ static void *msg_xfer(struct qaic_device *qdev, struct wrapper_list *wrappers, u mutex_lock(&qdev->cntl_mutex); if (!list_empty(&elem.list)) list_del(&elem.list); + /* resp_worker() processed the response but the wait was interrupted */ + else if (ret == -ERESTARTSYS) + ret = 0; if (!ret && !elem.buf) ret = -ETIMEDOUT; else if (ret > 0 && !elem.buf) @@ -1419,9 +1422,49 @@ static void resp_worker(struct work_struct *work) } mutex_unlock(&qdev->cntl_mutex); - if (!found) + if (!found) { + /* + * The user might have gone away at this point without waiting + * for QAIC_TRANS_DEACTIVATE_FROM_DEV transaction coming from + * the device. If this is not handled correctly, the host will + * not know that the DBC[n] has been freed on the device. + * Due to this failure in synchronization between the device and + * the host, if another user requests to activate a network, and + * the device assigns DBC[n] again, save_dbc_buf() will hang, + * waiting for dbc[n]->in_use to be set to false, which will not + * happen unless the qaic_dev_reset_clean_local_state() gets + * called by resetting the device (or re-inserting the module). + * + * As a solution, we look for QAIC_TRANS_DEACTIVATE_FROM_DEV + * transactions in the message before disposing of it, then + * handle releasing the DBC resources. + * + * Since the user has gone away, if the device could not + * deactivate the network (status != 0), there is no way to + * enable and reassign the DBC to the user. We can put trust in + * the device that it will release all the active DBCs in + * response to the QAIC_TRANS_TERMINATE_TO_DEV transaction, + * otherwise, the user can issue an soc_reset to the device. + */ + u32 msg_count = le32_to_cpu(msg->hdr.count); + u32 msg_len = le32_to_cpu(msg->hdr.len); + u32 len = 0; + int j; + + for (j = 0; j < msg_count && len < msg_len; ++j) { + struct wire_trans_hdr *trans_hdr; + + trans_hdr = (struct wire_trans_hdr *)(msg->data + len); + if (le32_to_cpu(trans_hdr->type) == QAIC_TRANS_DEACTIVATE_FROM_DEV) { + if (decode_deactivate(qdev, trans_hdr, &len, NULL)) + len += le32_to_cpu(trans_hdr->len); + } else { + len += le32_to_cpu(trans_hdr->len); + } + } /* request must have timed out, drop packet */ kfree(msg); + } kfree(resp); }