lantiq: xrx200: backport upstream network fixes

This series contains bug fixes that may occur under
memory pressure.

Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>

1 files changed, 33 insertions, 0 deletions

diff --git a/target/linux/lantiq/patches-5.10/0718-v6.0-net-lantiq_xrx200-fix-lock-under-memory-pressure.patch b/target/linux/lantiq/patches-5.10/0718-v6.0-net-lantiq_xrx200-fix-lock-under-memory-pressure.patch
new file mode 100644
index 0000000000..929ae57ace
--- /dev/null
+++ b/target/linux/lantiq/patches-5.10/0718-v6.0-net-lantiq_xrx200-fix-lock-under-memory-pressure.patch
@@ -0,0 +1,33 @@
+From c4b6e9341f930e4dd089231c0414758f5f1f9dbd Mon Sep 17 00:00:00 2001
+From: Aleksander Jan Bajkowski <olek2@wp.pl>
+Date: Wed, 24 Aug 2022 23:54:07 +0200
+Subject: [PATCH] net: lantiq_xrx200: fix lock under memory pressure
+
+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@wp.pl>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ drivers/net/ethernet/lantiq_xrx200.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+--- a/drivers/net/ethernet/lantiq_xrx200.c
++++ b/drivers/net/ethernet/lantiq_xrx200.c
+@@ -294,7 +294,7 @@ static int xrx200_poll_rx(struct napi_st
+ 			if (ret == XRX200_DMA_PACKET_IN_PROGRESS)
+ 				continue;
+ 			if (ret != XRX200_DMA_PACKET_COMPLETE)
+-				return ret;
++				break;
+ 			rx++;
+ 		} else {
+ 			break;