Messages in this thread | | | From | Alexei Starovoitov <> | Date | Tue, 7 Jun 2022 11:40:47 -0700 | Subject | Re: [PATCHv2 bpf 3/3] bpf: Force cookies array to follow symbols sorting |
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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
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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