On 2026/4/8 21:21 Jiri Olsa <[email protected]> write:
> On Wed, Apr 08, 2026 at 02:21:07PM +0800, Menglong Dong wrote:
> > The fsession attach type is missed in the verifier log in
> > check_get_func_ip(), bpf_check_attach_target() and check_attach_btf_id().
> > Update them to make the verifier log proper. Meanwhile, update the
> > corresponding selftests.
> >
> > Signed-off-by: Menglong Dong <[email protected]>
> > Acked-by: Leon Hwang <[email protected]>
> > ---
> > v2:
> > - add a missing FSESSION in bpf_check_attach_target()
> > ---
> > kernel/bpf/verifier.c | 10 +++++-----
> > tools/testing/selftests/bpf/prog_tests/exceptions.c | 8 ++++----
> > tools/testing/selftests/bpf/verifier/sleepable.c | 2 +-
> > 3 files changed, 10 insertions(+), 10 deletions(-)
> >
> > diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> > index 594260c1f382..beb660b4c3ec 100644
> > --- a/kernel/bpf/verifier.c
> > +++ b/kernel/bpf/verifier.c
> > @@ -11757,7 +11757,7 @@ static int check_get_func_ip(struct
> > bpf_verifier_env *env)
> >
> > if (type == BPF_PROG_TYPE_TRACING) {
> > if (!bpf_prog_has_trampoline(env->prog)) {
> > - verbose(env, "func %s#%d supported only for
> > fentry/fexit/fmod_ret programs\n",
> > + verbose(env, "func %s#%d supported only for
> > fentry/fexit/fsession/fmod_ret programs\n",
> > func_id_name(func_id), func_id);
> > return -ENOTSUPP;
> > }
> > @@ -25561,7 +25561,7 @@ int bpf_check_attach_target(struct bpf_verifier_log
> > *log,
> > btf = tgt_prog ? tgt_prog->aux->btf : prog->aux->attach_btf;
> > if (!btf) {
> > bpf_log(log,
> > - "FENTRY/FEXIT program can only be attached to another
> > program annotated with BTF\n");
> > + "FENTRY/FEXIT/FSESSION program can only be attached to
> > another program annotated with BTF\n");
>
> I wonder this should say 'Tracing program...' instead,
> we have other tracing types not covered in this error
Yeah, it make sense. I'll update it in V3.
Thanks!
Menglong Dong
>
> jirka
>
> > return -EINVAL;
> > }
> > t = btf_type_by_id(btf, btf_id);
> > @@ -25597,7 +25597,7 @@ int bpf_check_attach_target(struct bpf_verifier_log
> > *log,
> > if (aux->func && aux->func[subprog]->aux->exception_cb) {
> > bpf_log(log,
> > "%s programs cannot attach to exception
> > callback\n",
> > - prog_extension ? "Extension" : "FENTRY/FEXIT");
> > + prog_extension ? "Extension" :
> > "FENTRY/FEXIT/FSESSION");
> > return -EINVAL;
> > }
> > conservative = aux->func_info_aux[subprog].unreliable;
> > @@ -25686,7 +25686,7 @@ int bpf_check_attach_target(struct bpf_verifier_log
> > *log,
> > case BPF_TRACE_RAW_TP:
> > if (tgt_prog) {
> > bpf_log(log,
> > - "Only FENTRY/FEXIT progs are attachable to
> > another BPF prog\n");
> > + "Only FENTRY/FEXIT/FSESSION progs are
> > attachable to another BPF prog\n");
> > return -EINVAL;
> > }
> > if (!btf_type_is_typedef(t)) {
> > @@ -25952,7 +25952,7 @@ static int check_attach_btf_id(struct
> > bpf_verifier_env *env)
> > }
> >
> > if (prog->sleepable && !can_be_sleepable(prog)) {
> > - verbose(env, "Only fentry/fexit/fmod_ret, lsm, iter, uprobe,
> > and struct_ops programs can be sleepable\n");
> > + verbose(env, "Only fentry/fexit/fsession/fmod_ret, lsm, iter,
> > uprobe, and struct_ops programs can be sleepable\n");
> > return -EINVAL;
> > }
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/exceptions.c
> > b/tools/testing/selftests/bpf/prog_tests/exceptions.c
> > index 84ab73e08b0e..94a62fcd4543 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/exceptions.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/exceptions.c
> > @@ -128,7 +128,7 @@ static void test_exceptions_success(void)
> >
> > bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
> > "exception_cb_mod"),
> > "set_attach_target"))
> > goto done;
> > - }), "FENTRY/FEXIT programs cannot attach to exception
> > callback", 0);
> > + }), "FENTRY/FEXIT/FSESSION programs cannot attach to exception
> > callback", 0);
> >
> > if (test__start_subtest("throwing fentry -> exception_cb"))
> > RUN_EXT(-EINVAL, true, ({
> > @@ -138,7 +138,7 @@ static void test_exceptions_success(void)
> >
> > bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
> > "exception_cb_mod"),
> > "set_attach_target"))
> > goto done;
> > - }), "FENTRY/FEXIT programs cannot attach to exception
> > callback", 0);
> > + }), "FENTRY/FEXIT/FSESSION programs cannot attach to exception
> > callback", 0);
> >
> > if (test__start_subtest("non-throwing fexit -> exception_cb"))
> > RUN_EXT(-EINVAL, true, ({
> > @@ -148,7 +148,7 @@ static void test_exceptions_success(void)
> >
> > bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
> > "exception_cb_mod"),
> > "set_attach_target"))
> > goto done;
> > - }), "FENTRY/FEXIT programs cannot attach to exception
> > callback", 0);
> > + }), "FENTRY/FEXIT/FSESSION programs cannot attach to exception
> > callback", 0);
> >
> > if (test__start_subtest("throwing fexit -> exception_cb"))
> > RUN_EXT(-EINVAL, true, ({
> > @@ -158,7 +158,7 @@ static void test_exceptions_success(void)
> >
> > bpf_program__fd(skel->progs.exception_ext_mod_cb_runtime),
> > "exception_cb_mod"),
> > "set_attach_target"))
> > goto done;
> > - }), "FENTRY/FEXIT programs cannot attach to exception
> > callback", 0);
> > + }), "FENTRY/FEXIT/FSESSION programs cannot attach to exception
> > callback", 0);
> >
> > if (test__start_subtest("throwing extension (with custom cb) ->
> > exception_cb"))
> > RUN_EXT(-EINVAL, true, ({
> > diff --git a/tools/testing/selftests/bpf/verifier/sleepable.c
> > b/tools/testing/selftests/bpf/verifier/sleepable.c
> > index 1f0d2bdc673f..c2b7f5ebf168 100644
> > --- a/tools/testing/selftests/bpf/verifier/sleepable.c
> > +++ b/tools/testing/selftests/bpf/verifier/sleepable.c
> > @@ -85,7 +85,7 @@
> > .expected_attach_type = BPF_TRACE_RAW_TP,
> > .kfunc = "sched_switch",
> > .result = REJECT,
> > - .errstr = "Only fentry/fexit/fmod_ret, lsm, iter, uprobe, and
> > struct_ops programs can be sleepable",
> > + .errstr = "Only fentry/fexit/fsession/fmod_ret, lsm, iter, uprobe, and
> > struct_ops programs can be sleepable",
> > .flags = BPF_F_SLEEPABLE,
> > .runs = -1,
> > },
> > --
> > 2.53.0
> >
>
>
