Re: [PATCH bpf-next v2 3/3] selftests/bpf: Add selftest for attaching tracing programs to functions in deny list

[KaFai Wan <mannkafai@gmail.com>]

On Wed, 2025-07-16 at 18:37 -0700, Alexei Starovoitov wrote:
> On Mon, Jul 14, 2025 at 5:04 AM KaFai Wan <mannkafai@gmail.com>
> wrote:
> > 
> > The reuslt:
> > 
> >   $ tools/testing/selftests/bpf/test_progs --name=tracing_deny
> >   #467/1   tracing_deny/migrate_disable:OK
> >   #467     tracing_deny:OK
> >   Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED
> > 
> > Signed-off-by: KaFai Wan <mannkafai@gmail.com>
> > ---
> >  .../selftests/bpf/prog_tests/tracing_deny.c       | 11 +++++++++++
> >  tools/testing/selftests/bpf/progs/tracing_deny.c  | 15
> > +++++++++++++++
> >  2 files changed, 26 insertions(+)
> >  create mode 100644
> > tools/testing/selftests/bpf/prog_tests/tracing_deny.c
> >  create mode 100644
> > tools/testing/selftests/bpf/progs/tracing_deny.c
> > 
> > diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_deny.c
> > b/tools/testing/selftests/bpf/prog_tests/tracing_deny.c
> > new file mode 100644
> > index 000000000000..460c59a9667f
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/prog_tests/tracing_deny.c
> > @@ -0,0 +1,11 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +
> > +#include <test_progs.h>
> > +#include "tracing_deny.skel.h"
> > +
> > +void test_tracing_deny(void)
> > +{
> > +       /* migrate_disable depends on CONFIG_SMP */
> > +       if (libbpf_find_vmlinux_btf_id("migrate_disable",
> > BPF_TRACE_FENTRY) > 0)
> > +               RUN_TESTS(tracing_deny);
> > +}
> > diff --git a/tools/testing/selftests/bpf/progs/tracing_deny.c
> > b/tools/testing/selftests/bpf/progs/tracing_deny.c
> > new file mode 100644
> > index 000000000000..98ef834f0b6d
> > --- /dev/null
> > +++ b/tools/testing/selftests/bpf/progs/tracing_deny.c
> > @@ -0,0 +1,15 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +
> > +#include <linux/bpf.h>
> > +#include <bpf/bpf_helpers.h>
> > +#include <bpf/bpf_tracing.h>
> > +#include "bpf_misc.h"
> > +
> > +char _license[] SEC("license") = "GPL";
> > +
> > +SEC("fentry/migrate_disable")
> > +__failure __msg("Attaching tracing programs to function
> > 'migrate_disable' is rejected.")
> > +int BPF_PROG(migrate_disable)
> > +{
> > +       return 0;
> > +}
> 
> Please roll these two tiny files into existing files in progs/ and
> prog_tests/
> directories.
> Every file takes time to compile 4 times, so let's avoid unnecessary
> overhead.
> 

Okay, will update it in v3.

> --
> pw-bot: cr

-- 
Thanks,
KaFai