tree 679251f45a7a1ab02886e816ff418fdc4f227cb8
parent 5474b13233eb46ab9b80f12f9c8003aabd383283
author Daniel Borkmann <daniel@iogearbox.net> 1432672543 +0200
committer David S. Miller <davem@davemloft.net> 1432749959 -0400

test_bpf: add similarly conflicting jump test case only for classic

While 3b52960266a3 ("test_bpf: add more eBPF jump torture cases")
added the int3 bug test case only for eBPF, which needs exactly 11
passes to converge, here's a version for classic BPF with 11 passes,
and one that would need 70 passes on x86_64 to actually converge for
being successfully JITed. Effectively, all jumps are being optimized
out resulting in a JIT image of just 89 bytes (from originally max
BPF insns), only returning K.

Might be useful as a receipe for folks wanting to craft a test case
when backporting the fix in commit 3f7352bf21f8 ("x86: bpf_jit: fix
compilation of large bpf programs") while not having eBPF. The 2nd
one is delegated to the interpreter as the last pass still results
in shrinking, in other words, this one won't be JITed on x86_64.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>