[PATCH 5.4 076/111] can: m_can: m_can_rx_peripheral(): fix RX being blocked by errors

From: Greg Kroah-Hartman
Date: Mon Mar 29 2021 - 04:25:52 EST


From: Torin Cooper-Bennun <torin@xxxxxxxxxxxxxxxxxx>

[ Upstream commit e98d9ee64ee2cc9b1d1a8e26610ec4d0392ebe50 ]

For M_CAN peripherals, m_can_rx_handler() was called with quota = 1,
which caused any error handling to block RX from taking place until
the next time the IRQ handler is called. This had been observed to
cause RX to be blocked indefinitely in some cases.

This is fixed by calling m_can_rx_handler with a sensibly high quota.

Fixes: f524f829b75a ("can: m_can: Create a m_can platform framework")
Link: https://lore.kernel.org/r/20210303144350.4093750-1-torin@xxxxxxxxxxxxxxxxxx
Suggested-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Torin Cooper-Bennun <torin@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/can/m_can/m_can.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index cf72a7e464ec..b2224113987c 100644
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -839,7 +839,7 @@ static int m_can_rx_peripheral(struct net_device *dev)
{
struct m_can_classdev *cdev = netdev_priv(dev);

- m_can_rx_handler(dev, 1);
+ m_can_rx_handler(dev, M_CAN_NAPI_WEIGHT);

m_can_enable_all_interrupts(cdev);

--
2.30.1