From: Ilya Leoshkevich <iii@linux.ibm.com>
Date: Sat, 28 Jan 2023 01:06:29 +0100
Subject: [PATCH] selftests/bpf: Fix xdp_do_redirect on s390x
References: bsc#1012628
Patch-mainline: 6.2.3
Git-commit: 06c1865b0b0c7820ea53af2394dd7aff31100295

[ Upstream commit 06c1865b0b0c7820ea53af2394dd7aff31100295 ]

s390x cache line size is 256 bytes, so skb_shared_info must be aligned
on a much larger boundary than for x86. This makes the maximum packet
size smaller.

Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Link: https://lore.kernel.org/r/20230128000650.1516334-11-iii@linux.ibm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Stable-dep-of: 6c20822fada1 ("bpf, test_run: fix &xdp_frame misplacement for LIVE_FRAMES")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 tools/testing/selftests/bpf/prog_tests/xdp_do_redirect.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/xdp_do_redirect.c b/tools/testing/selftests/bpf/prog_tests/xdp_do_redirect.c
index a50971c6..ac70e871 100644
--- a/tools/testing/selftests/bpf/prog_tests/xdp_do_redirect.c
+++ b/tools/testing/selftests/bpf/prog_tests/xdp_do_redirect.c
@@ -65,7 +65,11 @@ static int attach_tc_prog(struct bpf_tc_hook *hook, int fd)
 /* The maximum permissible size is: PAGE_SIZE - sizeof(struct xdp_page_head) -
  * sizeof(struct skb_shared_info) - XDP_PACKET_HEADROOM = 3368 bytes
  */
+#if defined(__s390x__)
+#define MAX_PKT_SIZE 3176
+#else
 #define MAX_PKT_SIZE 3368
+#endif
 static void test_max_pkt_size(int fd)
 {
 	char data[MAX_PKT_SIZE + 1] = {};
-- 
2.35.3