Messages in this thread | | | From | Jiri Olsa <> | Date | Tue, 7 Jun 2022 21:55:58 +0200 | Subject | Re: [PATCHv2 bpf 3/3] bpf: Force cookies array to follow symbols sorting |
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On Tue, Jun 07, 2022 at 11:40:47AM -0700, Alexei Starovoitov wrote: > On Mon, Jun 6, 2022 at 11:48 AM Jiri Olsa <jolsa@kernel.org> wrote: > > > > When user specifies symbols and cookies for kprobe_multi link > > interface it's very likely the cookies will be misplaced and > > returned to wrong functions (via get_attach_cookie helper). > > > > The reason is that to resolve the provided functions we sort > > them before passing them to ftrace_lookup_symbols, but we do > > not do the same sort on the cookie values. > > > > Fixing this by using sort_r function with custom swap callback > > that swaps cookie values as well. > > > > Fixes: 0236fec57a15 ("bpf: Resolve symbols with ftrace_lookup_symbols for kprobe multi link") > > Signed-off-by: Jiri Olsa <jolsa@kernel.org> > > It looks good, but something in this patch is causing a regression: > ./test_progs -t kprobe_multi > test_kprobe_multi_test:PASS:load_kallsyms 0 nsec > #80/1 kprobe_multi_test/skel_api:OK > #80/2 kprobe_multi_test/link_api_addrs:OK > #80/3 kprobe_multi_test/link_api_syms:OK > #80/4 kprobe_multi_test/attach_api_pattern:OK > #80/5 kprobe_multi_test/attach_api_addrs:OK > #80/6 kprobe_multi_test/attach_api_syms:OK > #80/7 kprobe_multi_test/attach_api_fails:OK > test_bench_attach:PASS:get_syms 0 nsec > test_bench_attach:PASS:kprobe_multi_empty__open_and_load 0 nsec > libbpf: prog 'test_kprobe_empty': failed to attach: No such process > test_bench_attach:FAIL:bpf_program__attach_kprobe_multi_opts > unexpected error: -3 > #80/8 kprobe_multi_test/bench_attach:FAIL > #80 kprobe_multi_test:FAIL
looks like kallsyms search failed to find some symbol, but I can't reproduce with:
./vmtest.sh -- ./test_progs -t kprobe_multi
can you share .config you used?
thanks, jirka
> > CI is unfortunately green, because we don't run it there: > #80/1 kprobe_multi_test/skel_api:OK > #80/2 kprobe_multi_test/link_api_addrs:OK > #80/3 kprobe_multi_test/link_api_syms:OK > #80/4 kprobe_multi_test/attach_api_pattern:OK > #80/5 kprobe_multi_test/attach_api_addrs:OK > #80/6 kprobe_multi_test/attach_api_syms:OK > #80/7 kprobe_multi_test/attach_api_fails:OK > #80 kprobe_multi_test:OK
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