On Fri, Dec 15, 2023 at 01:22:35PM -0800, Andrii Nakryiko wrote: > On Fri, Dec 15, 2023 at 6:42 AM Yonghong Song <yonghong.song@xxxxxxxxx> wrote: > > > > > > On 12/15/23 6:24 AM, Jiri Olsa wrote: > > > On Fri, Dec 15, 2023 at 10:16:27AM +0100, Jiri Olsa wrote: > > >> hi, > > >> The bpf CI is broken due to clang emitting 2 functions for > > >> bpf_fentry_test7: > > >> > > >> # cat available_filter_functions | grep bpf_fentry_test7 > > >> bpf_fentry_test7 > > >> bpf_fentry_test7.specialized.1 > > >> > > >> The tests attach to 'bpf_fentry_test7' while the function with > > >> '.specialized.1' suffix is executed in bpf_prog_test_run_tracing. > > >> > > >> It looks like clang optimalization that comes from passing 0 > > >> as argument and returning it directly in bpf_fentry_test7. > > >> > > >> I'm not sure there's a way to disable this, so far I came > > >> up with solution below that passes real pointer, but I think > > >> that was not the original intention for the test. > > >> > > >> We had issue with this function back in august: > > >> 32337c0a2824 bpf: Prevent inlining of bpf_fentry_test7() > > >> > > >> I'm not sure why it started to show now? was clang updated for CI? > > >> > > >> I'll try to find out more, but any clang ideas are welcome ;-) > > >> > > >> thanks, > > >> jirka > > > > > > hm, there seems to be fix in bpf-next for this one: > > > > > > b16904fd9f01 bpf: Fix a few selftest failures due to llvm18 change > > > > Maybe submit a patch to https://github.com/kernel-patches/vmtest/tree/master/ci/diffs? > > That is typically the place to have temporary patches to workaround ci failures. > > > > To get bpf/master back to green CI I did it meanwhile ([0]). Jiri, > please check the PR to be familiar with the process for the future > similar mitigations, thanks. > > [0] https://github.com/kernel-patches/vmtest/pull/258 great, thanks jirka > > > > > > > jirka > > > > > >> > > >> --- > > >> diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c > > >> index c9fdcc5cdce1..33208eec9361 100644 > > >> --- a/net/bpf/test_run.c > > >> +++ b/net/bpf/test_run.c > > >> @@ -543,7 +543,7 @@ struct bpf_fentry_test_t { > > >> int noinline bpf_fentry_test7(struct bpf_fentry_test_t *arg) > > >> { > > >> asm volatile (""); > > >> - return (long)arg; > > >> + return 0; > > >> } > > >> > > >> int noinline bpf_fentry_test8(struct bpf_fentry_test_t *arg) > > >> @@ -668,7 +668,7 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog, > > >> bpf_fentry_test4((void *)7, 8, 9, 10) != 34 || > > >> bpf_fentry_test5(11, (void *)12, 13, 14, 15) != 65 || > > >> bpf_fentry_test6(16, (void *)17, 18, 19, (void *)20, 21) != 111 || > > >> - bpf_fentry_test7((struct bpf_fentry_test_t *)0) != 0 || > > >> + bpf_fentry_test7(&arg) != 0 || > > >> bpf_fentry_test8(&arg) != 0 || > > >> bpf_fentry_test9(&retval) != 0) > > >> goto out; > > >> diff --git a/tools/testing/selftests/bpf/progs/fentry_test.c b/tools/testing/selftests/bpf/progs/fentry_test.c > > >> index 52a550d281d9..95c5c34ccaa8 100644 > > >> --- a/tools/testing/selftests/bpf/progs/fentry_test.c > > >> +++ b/tools/testing/selftests/bpf/progs/fentry_test.c > > >> @@ -64,7 +64,7 @@ __u64 test7_result = 0; > > >> SEC("fentry/bpf_fentry_test7") > > >> int BPF_PROG(test7, struct bpf_fentry_test_t *arg) > > >> { > > >> - if (!arg) > > >> + if (arg) > > >> test7_result = 1; > > >> return 0; > > >> } > > >> diff --git a/tools/testing/selftests/bpf/progs/fexit_test.c b/tools/testing/selftests/bpf/progs/fexit_test.c > > >> index 8f1ccb7302e1..ffb30236ca02 100644 > > >> --- a/tools/testing/selftests/bpf/progs/fexit_test.c > > >> +++ b/tools/testing/selftests/bpf/progs/fexit_test.c > > >> @@ -65,7 +65,7 @@ __u64 test7_result = 0; > > >> SEC("fexit/bpf_fentry_test7") > > >> int BPF_PROG(test7, struct bpf_fentry_test_t *arg) > > >> { > > >> - if (!arg) > > >> + if (arg) > > >> test7_result = 1; > > >> return 0; > > >> }
