Merge branch 'bpf-fix-a-couple-of-test-failures-with-lto-kernel'
Yonghong Song says:
====================
bpf: Fix a couple of test failures with LTO kernel
With a LTO kernel built with clang, with one of earlier version of kernel,
I encountered two test failures, ksyms and kprobe_multi_bench_attach/kernel.
Now with latest bpf-next, only kprobe_multi_bench_attach/kernel failed.
But it is possible in the future ksyms selftest may fail again.
Both test failures are due to static variable/function renaming
due to cross-file inlining. For Ksyms failure, the solution is
to strip .llvm.<hash> suffixes for symbols in /proc/kallsyms before
comparing against the ksym in bpf program.
For kprobe_multi_bench_attach/kernel failure, the solution is
to either provide names in /proc/kallsyms to the kernel or
ignore those names who have .llvm.<hash> suffix since the kernel
sym name comparison is against /proc/kallsyms.
Please see each individual patches for details.
Changelogs:
v2 -> v3:
- no need to check config file, directly so strstr with '.llvm.'.
- for kprobe_multi_bench with syms, instead of skipping the syms,
consult /proc/kallyms to find corresponding names.
- add a test with populating addrs to the kernel for kprobe
multi attach.
v1 -> v2:
- Let libbpf handle .llvm.<hash suffixes since it may impact
bpf program ksym.
====================
Link: https://lore.kernel.org/r/20240326041443.1197498-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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