From: Yonghong Song <yhs@fb.com>
Date: Tue, 14 Sep 2021 15:30:41 -0700
Subject: selftests/bpf: Change NAME_NTH/IS_NAME_NTH for BTF_KIND_TAG format
Patch-mainline: v5.16-rc1
Git-commit: 3df3bd68d4811bccc74adc04d4d84512957a1a07
References: jsc#PED-1377

BTF_KIND_TAG ELF format has a component_idx which might have value -1.
test_btf may confuse it with common_type.name as NAME_NTH checkes
high 16bit to be 0xffff. Change NAME_NTH high 16bit check to be
0xfffe so it won't confuse with component_idx.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210914223041.248009-1-yhs@fb.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 tools/testing/selftests/bpf/prog_tests/btf.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/tools/testing/selftests/bpf/prog_tests/btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf.c
@@ -39,8 +39,8 @@ static bool always_log;
 #define BTF_END_RAW 0xdeadbeef
 #define NAME_TBD 0xdeadb33f
 
-#define NAME_NTH(N) (0xffff0000 | N)
-#define IS_NAME_NTH(X) ((X & 0xffff0000) == 0xffff0000)
+#define NAME_NTH(N) (0xfffe0000 | N)
+#define IS_NAME_NTH(X) ((X & 0xffff0000) == 0xfffe0000)
 #define GET_NAME_NTH_IDX(X) (X & 0x0000ffff)
 
 #define MAX_NR_RAW_U32 1024