net: ethernet: mvneta: fix MVNETA_SKB_HEADROOM alignment

Commit ca23cb0bc50f ("mvneta: MVNETA_SKB_HEADROOM set last 3 bits to zero")
added headroom alignment check against 8.
Hovewer (if we imagine that NET_SKB_PAD or XDP_PACKET_HEADROOM is not
aligned to cacheline size), it actually aligns headroom down, while
skb/xdp_buff headroom should be *at least* equal to one of the values
(depending on XDP prog presence).
So, fix the check to align the value up. This satisfies both
hardware/driver and network stack requirements.

Fixes: ca23cb0bc50f ("mvneta: MVNETA_SKB_HEADROOM set last 3 bits to zero")
Signed-off-by: Alexander Lobakin <bloodyreaper@yandex.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
index 011cd26..4cc9abd 100644 (file)
--- a/drivers/net/ethernet/marvell/mvneta.c
+++ b/drivers/net/ethernet/marvell/mvneta.c
@@ -325,7 +325,7 @@
              cache_line_size())
 
 /* Driver assumes that the last 3 bits are 0 */
-#define MVNETA_SKB_HEADROOM    (max(XDP_PACKET_HEADROOM, NET_SKB_PAD) & ~0x7)
+#define MVNETA_SKB_HEADROOM    ALIGN(max(NET_SKB_PAD, XDP_PACKET_HEADROOM), 8)
 #define MVNETA_SKB_PAD (SKB_DATA_ALIGN(sizeof(struct skb_shared_info) + \
                         MVNETA_SKB_HEADROOM))
 #define MVNETA_SKB_SIZE(len)   (SKB_DATA_ALIGN(len) + MVNETA_SKB_PAD)