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From:   Daniel Xu <dxu@dxuuu.xyz>
To:     ast@kernel.org, andrii@kernel.org, shuah@kernel.org,
        daniel@iogearbox.net, steffen.klassert@secunet.com,
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        kpsingh@kernel.org, sdf@google.com, haoluo@google.com,
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        linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org,
        devel@linux-ipsec.org
Subject: [RFC bpf-next 5/6] bpf: selftests: test_tunnel: Disable CO-RE relocations
Date:   Fri, 27 Oct 2023 12:46:21 -0600
Message-ID: <111a64c3e6ccda6b8a2826491715d4e8a645e384.1698431765.git.dxu@dxuuu.xyz>
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Switching to vmlinux.h definitions seems to make the verifier very
unhappy with bitfield accesses. The error is:

    ; md.u.md2.dir = direction;
    33: (69) r1 = *(u16 *)(r2 +11)
    misaligned stack access off (0x0; 0x0)+-64+11 size 2

It looks like disabling CO-RE relocations seem to make the error go
away.

Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
---
 tools/testing/selftests/bpf/progs/test_tunnel_kern.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/testing/selftests/bpf/progs/test_tunnel_kern.c b/tools/testing/selftests/bpf/progs/test_tunnel_kern.c
index 3065a716544d..ec7e04e012ae 100644
--- a/tools/testing/selftests/bpf/progs/test_tunnel_kern.c
+++ b/tools/testing/selftests/bpf/progs/test_tunnel_kern.c
@@ -6,6 +6,7 @@
  * modify it under the terms of version 2 of the GNU General Public
  * License as published by the Free Software Foundation.
  */
+#define BPF_NO_PRESERVE_ACCESS_INDEX
 #include "vmlinux.h"
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_endian.h>
-- 
2.42.0