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| author | Ilya Leoshkevich <[email protected]> | 2020-07-17 16:53:25 +0000 |
|---|---|---|
| committer | Alexei Starovoitov <[email protected]> | 2020-07-21 20:26:25 +0000 |
| commit | 1491b73311a15bb5beeab5d30e03bff761ef6c18 (patch) | |
| tree | fcef3f57edcb12923456221bdbdb6532a589368d /tools/lib/bpf/bpf_helpers.h | |
| parent | s390/bpf: Use brcl for jumping to exit_ip if necessary (diff) | |
| download | kernel-1491b73311a15bb5beeab5d30e03bff761ef6c18.tar.gz kernel-1491b73311a15bb5beeab5d30e03bff761ef6c18.zip | |
s390/bpf: Tolerate not converging code shrinking
"BPF_MAXINSNS: Maximum possible literals" unnecessarily falls back to
the interpreter because of failing sanity check in bpf_set_addr. The
problem is that there are a lot of branches that can be shrunk, and
doing so opens up the possibility to shrink even more. This process
does not converge after 3 passes, causing code offsets to change during
the codegen pass, which must never happen.
Fix by inserting nops during codegen pass in order to preserve code
offets.
Fixes: 4e9b4a6883dd ("s390/bpf: Use relative long branches")
Signed-off-by: Ilya Leoshkevich <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Diffstat (limited to 'tools/lib/bpf/bpf_helpers.h')
0 files changed, 0 insertions, 0 deletions