[PATCH net v2 2/3] net: lantiq_xrx200: fix lock under memory pressure

From: Aleksander Jan Bajkowski
Date: Mon Aug 15 2022 - 10:58:26 EST


When the xrx200_hw_receive() function returns -ENOMEM, the NAPI poll
function immediately returns an error.
This is incorrect for two reasons:
* the function terminates without enabling interrupts or scheduling NAPI,
* the error code (-ENOMEM) is returned instead of the number of received
packets.

After the first memory allocation failure occurs, packet reception is
locked due to disabled interrupts from DMA..

Fixes: fe1a56420cf2 ("net: lantiq: Add Lantiq / Intel VRX200 Ethernet driver")
Signed-off-by: Aleksander Jan Bajkowski <olek2@xxxxx>
---
drivers/net/ethernet/lantiq_xrx200.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c
index 6a83a6c19484..8f9155eacdb3 100644
--- a/drivers/net/ethernet/lantiq_xrx200.c
+++ b/drivers/net/ethernet/lantiq_xrx200.c
@@ -295,7 +295,7 @@ static int xrx200_poll_rx(struct napi_struct *napi, int budget)
if (ret == XRX200_DMA_PACKET_IN_PROGRESS)
continue;
if (ret != XRX200_DMA_PACKET_COMPLETE)
- return ret;
+ break;
rx++;
} else {
break;
--
2.30.2