Hi Jakub, On Fri, 6 Oct 2023 14:47:02 -0700 Jakub Kicinski <kuba@kernel.org> wrote:
On Thu, 28 Sep 2023 09:06:28 +0200 Herve Codina wrote:
+static int qmc_hdlc_close(struct net_device *netdev) +{ + struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev); + struct qmc_hdlc_desc *desc; + int i; + + netif_stop_queue(netdev); + + qmc_chan_stop(qmc_hdlc->qmc_chan, QMC_CHAN_ALL); + qmc_chan_reset(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
stopping the queue looks a bit racy, a completion may come in and restart the queue
Indeed, qmc_hdlc_xmit_complete() completion can restart the queue. I will call netif_stop_queue() after calling qmc_chan_stop/reset(). This is the simple way to fix that without adding an internal flag. Thanks for pointing that. Best regards, Hervé
+ for (i = 0; i < ARRAY_SIZE(qmc_hdlc->tx_descs); i++) { + desc = &qmc_hdlc->tx_descs[i]; + if (!desc->skb) + continue; + dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, + DMA_TO_DEVICE); + kfree_skb(desc->skb); + desc->skb = NULL; + } + + for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) { + desc = &qmc_hdlc->rx_descs[i]; + if (!desc->skb) + continue; + dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, + DMA_FROM_DEVICE); + kfree_skb(desc->skb); + desc->skb = NULL; + } + + hdlc_close(netdev);