From: "Nikita V. Shirokov" <tehnerd@tehnerd.com>
Date: Tue, 17 Apr 2018 21:42:17 -0700
Subject: bpf: make cavium thunder compatible w/ bpf_xdp_adjust_tail
Patch-mainline: v4.18-rc1
Git-commit: a48ce00f9aeb6ce1227e291c36a0fa4995273144
References: bsc#1110096

w/ bpf_xdp_adjust_tail helper xdp's data_end pointer could be changed as
well (only "decrease" of pointer's location is going to be supported).
changing of this pointer will change packet's size.
for cavium's thunder driver we will just calculate packet's length
unconditionally

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/cavium/thunder/nicvf_main.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
@@ -537,9 +537,9 @@ static inline bool nicvf_xdp_rx(struct n
 	action = bpf_prog_run_xdp(prog, &xdp);
 	rcu_read_unlock();
 
+	len = xdp.data_end - xdp.data;
 	/* Check if XDP program has changed headers */
 	if (orig_data != xdp.data) {
-		len = xdp.data_end - xdp.data;
 		offset = orig_data - xdp.data;
 		dma_addr -= offset;
 	}