[PATCH 1/3] can: mcp251xfd: mcp251xfd_remove(): fix order of unregistration calls
From: Marc Kleine-Budde
Date: Fri May 02 2025 - 10:16:21 EST
If a driver is removed, the driver framework invokes the driver's
remove callback. A CAN driver's remove function calls
unregister_candev(), which calls net_device_ops::ndo_stop further down
in the call stack for interfaces which are in the "up" state.
With the mcp251xfd driver the removal of the module causes the
following warning:
| WARNING: CPU: 0 PID: 352 at net/core/dev.c:7342 __netif_napi_del_locked+0xc8/0xd8
as can_rx_offload_del() deletes the NAPI, while it is still active,
because the interface is still up.
To fix the warning, first unregister the network interface, which
calls net_device_ops::ndo_stop, which disables the NAPI, and then call
can_rx_offload_del().
Fixes: 55e5b97f003e ("can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
index 3bc56517fe7a..dd0b3fb42f1b 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c
@@ -2174,8 +2174,8 @@ static void mcp251xfd_remove(struct spi_device *spi)
struct mcp251xfd_priv *priv = spi_get_drvdata(spi);
struct net_device *ndev = priv->ndev;
- can_rx_offload_del(&priv->offload);
mcp251xfd_unregister(priv);
+ can_rx_offload_del(&priv->offload);
spi->max_speed_hz = priv->spi_max_speed_hz_orig;
free_candev(ndev);
}
--
2.47.2