From: Andreas Larsson <andreas@gaisler.com> stable inclusion from stable-v5.10.115 commit 11adc9ab3eb36ef31bcb4f6d2cda3d7399bcbb49 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I5IZ9C Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 2873d4d52f7c52d60b316ba6c47bd7122b5a9861 upstream. The previous split budget between TX and RX made it return not using the entire budget but at the same time not having calling called napi_complete. This sometimes led to the poll to not be called, and at the same time having TX and RX interrupts disabled resulting in the driver getting stuck. Fixes: 6cec9b07fe6a ("can: grcan: Add device driver for GRCAN and GRHCAN cores") Link: https://lore.kernel.org/all/20220429084656.29788-4-andreas@gaisler.com Cc: stable@vger.kernel.org Signed-off-by: Andreas Larsson <andreas@gaisler.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com> Acked-by: Xie XiuQi <xiexiuqi@huawei.com> --- drivers/net/can/grcan.c | 22 +++++++--------------- 1 file changed, 7 insertions(+), 15 deletions(-) diff --git a/drivers/net/can/grcan.c b/drivers/net/can/grcan.c index beefa095259b..4923f9ac6a43 100644 --- a/drivers/net/can/grcan.c +++ b/drivers/net/can/grcan.c @@ -1137,7 +1137,7 @@ static int grcan_close(struct net_device *dev) return 0; } -static int grcan_transmit_catch_up(struct net_device *dev, int budget) +static void grcan_transmit_catch_up(struct net_device *dev) { struct grcan_priv *priv = netdev_priv(dev); unsigned long flags; @@ -1145,7 +1145,7 @@ static int grcan_transmit_catch_up(struct net_device *dev, int budget) spin_lock_irqsave(&priv->lock, flags); - work_done = catch_up_echo_skb(dev, budget, true); + work_done = catch_up_echo_skb(dev, -1, true); if (work_done) { if (!priv->resetting && !priv->closing && !(priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)) @@ -1159,8 +1159,6 @@ static int grcan_transmit_catch_up(struct net_device *dev, int budget) } spin_unlock_irqrestore(&priv->lock, flags); - - return work_done; } static int grcan_receive(struct net_device *dev, int budget) @@ -1242,19 +1240,13 @@ static int grcan_poll(struct napi_struct *napi, int budget) struct net_device *dev = priv->dev; struct grcan_registers __iomem *regs = priv->regs; unsigned long flags; - int tx_work_done, rx_work_done; - int rx_budget = budget / 2; - int tx_budget = budget - rx_budget; + int work_done; - /* Half of the budget for receiving messages */ - rx_work_done = grcan_receive(dev, rx_budget); + work_done = grcan_receive(dev, budget); - /* Half of the budget for transmitting messages as that can trigger echo - * frames being received - */ - tx_work_done = grcan_transmit_catch_up(dev, tx_budget); + grcan_transmit_catch_up(dev); - if (rx_work_done < rx_budget && tx_work_done < tx_budget) { + if (work_done < budget) { napi_complete(napi); /* Guarantee no interference with a running reset that otherwise @@ -1271,7 +1263,7 @@ static int grcan_poll(struct napi_struct *napi, int budget) spin_unlock_irqrestore(&priv->lock, flags); } - return rx_work_done + tx_work_done; + return work_done; } /* Work tx bug by waiting while for the risky situation to clear. If that fails, -- 2.20.1