Re: [PATCHv4 bpf-next 6/7] selftests/bpf: Add uretprobe compat test

[Andrii Nakryiko <andrii.nakryiko@gmail.com>]

On Thu, May 2, 2024 at 5:24 AM Jiri Olsa <jolsa@kernel.org> wrote:
>
> Adding test that adds return uprobe inside 32-bit task
> and verify the return uprobe and attached bpf programs
> get properly executed.
>
> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
>  tools/testing/selftests/bpf/.gitignore        |  1 +
>  tools/testing/selftests/bpf/Makefile          |  7 ++-
>  .../selftests/bpf/prog_tests/uprobe_syscall.c | 60 +++++++++++++++++++
>  3 files changed, 67 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
> index f1aebabfb017..69d71223c0dd 100644
> --- a/tools/testing/selftests/bpf/.gitignore
> +++ b/tools/testing/selftests/bpf/.gitignore
> @@ -45,6 +45,7 @@ test_cpp
>  /veristat
>  /sign-file
>  /uprobe_multi
> +/uprobe_compat
>  *.ko
>  *.tmp
>  xskxceiver
> diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
> index 82247aeef857..a94352162290 100644
> --- a/tools/testing/selftests/bpf/Makefile
> +++ b/tools/testing/selftests/bpf/Makefile
> @@ -133,7 +133,7 @@ TEST_GEN_PROGS_EXTENDED = test_sock_addr test_skb_cgroup_id_user \
>         xskxceiver xdp_redirect_multi xdp_synproxy veristat xdp_hw_metadata \
>         xdp_features bpf_test_no_cfi.ko
>
> -TEST_GEN_FILES += liburandom_read.so urandom_read sign-file uprobe_multi
> +TEST_GEN_FILES += liburandom_read.so urandom_read sign-file uprobe_multi uprobe_compat
>
>  ifneq ($(V),1)
>  submake_extras := feature_display=0
> @@ -631,6 +631,7 @@ TRUNNER_EXTRA_FILES := $(OUTPUT)/urandom_read $(OUTPUT)/bpf_testmod.ko      \
>                        $(OUTPUT)/xdp_synproxy                           \
>                        $(OUTPUT)/sign-file                              \
>                        $(OUTPUT)/uprobe_multi                           \
> +                      $(OUTPUT)/uprobe_compat                          \
>                        ima_setup.sh                                     \
>                        verify_sig_setup.sh                              \
>                        $(wildcard progs/btf_dump_test_case_*.c)         \
> @@ -752,6 +753,10 @@ $(OUTPUT)/uprobe_multi: uprobe_multi.c
>         $(call msg,BINARY,,$@)
>         $(Q)$(CC) $(CFLAGS) -O0 $(LDFLAGS) $^ $(LDLIBS) -o $@
>
> +$(OUTPUT)/uprobe_compat:
> +       $(call msg,BINARY,,$@)
> +       $(Q)echo "int main() { return 0; }" | $(CC) $(CFLAGS) -xc -m32 -O0 - -o $@
> +
>  EXTRA_CLEAN := $(SCRATCH_DIR) $(HOST_SCRATCH_DIR)                      \
>         prog_tests/tests.h map_tests/tests.h verifier/tests.h           \
>         feature bpftool                                                 \
> diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> index c6fdb8c59ea3..bfea9a0368a4 100644
> --- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c
> @@ -5,6 +5,7 @@
>  #ifdef __x86_64__
>
>  #include <unistd.h>
> +#include <stdlib.h>
>  #include <asm/ptrace.h>
>  #include <linux/compiler.h>
>  #include <linux/stringify.h>
> @@ -297,6 +298,58 @@ static void test_uretprobe_syscall_call(void)
>         close(go[1]);
>         close(go[0]);
>  }
> +
> +static void test_uretprobe_compat(void)
> +{
> +       LIBBPF_OPTS(bpf_uprobe_multi_opts, opts,
> +               .retprobe = true,
> +       );
> +       struct uprobe_syscall_executed *skel;
> +       int err, go[2], pid, c, status;
> +
> +       if (pipe(go))
> +               return;

ASSERT_OK() missing, like in the previous patch

Thanks for switching to pipe() + global variable instead of using trace_pipe.

Acked-by: Andrii Nakryiko <andrii@kernel.org>

> +
> +       skel = uprobe_syscall_executed__open_and_load();
> +       if (!ASSERT_OK_PTR(skel, "uprobe_syscall_executed__open_and_load"))
> +               goto cleanup;
> +

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