Adding bpf_cookie test for kprobe attached by fprobe link.
Signed-off-by: Jiri Olsa <[email protected]>
---
.../selftests/bpf/prog_tests/bpf_cookie.c | 73 +++++++++++++++++++
.../selftests/bpf/progs/fprobe_bpf_cookie.c | 62 ++++++++++++++++
2 files changed, 135 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
index cd10df6cd0fc..bf70d859c598 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
@@ -7,6 +7,7 @@
#include <unistd.h>
#include <test_progs.h>
#include "test_bpf_cookie.skel.h"
+#include "fprobe_bpf_cookie.skel.h"
/* uprobe attach point */
static void trigger_func(void)
@@ -63,6 +64,76 @@ static void kprobe_subtest(struct test_bpf_cookie *skel)
bpf_link__destroy(retlink2);
}
+static void fprobe_subtest(void)
+{
+ DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
+ int err, prog_fd, link1_fd = -1, link2_fd = -1;
+ struct fprobe_bpf_cookie *skel = NULL;
+ __u32 duration = 0, retval;
+ __u64 addrs[8], cookies[8];
+
+ skel = fprobe_bpf_cookie__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
+ goto cleanup;
+
+ kallsyms_find("bpf_fentry_test1", &addrs[0]);
+ kallsyms_find("bpf_fentry_test2", &addrs[1]);
+ kallsyms_find("bpf_fentry_test3", &addrs[2]);
+ kallsyms_find("bpf_fentry_test4", &addrs[3]);
+ kallsyms_find("bpf_fentry_test5", &addrs[4]);
+ kallsyms_find("bpf_fentry_test6", &addrs[5]);
+ kallsyms_find("bpf_fentry_test7", &addrs[6]);
+ kallsyms_find("bpf_fentry_test8", &addrs[7]);
+
+ cookies[0] = 1;
+ cookies[1] = 2;
+ cookies[2] = 3;
+ cookies[3] = 4;
+ cookies[4] = 5;
+ cookies[5] = 6;
+ cookies[6] = 7;
+ cookies[7] = 8;
+
+ opts.fprobe.addrs = (__u64) &addrs;
+ opts.fprobe.cnt = 8;
+ opts.fprobe.bpf_cookies = (__u64) &cookies;
+ prog_fd = bpf_program__fd(skel->progs.test2);
+
+ link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
+ if (!ASSERT_GE(link1_fd, 0, "link1_fd"))
+ return;
+
+ cookies[0] = 8;
+ cookies[1] = 7;
+ cookies[2] = 6;
+ cookies[3] = 5;
+ cookies[4] = 4;
+ cookies[5] = 3;
+ cookies[6] = 2;
+ cookies[7] = 1;
+
+ opts.flags = BPF_F_FPROBE_RETURN;
+ prog_fd = bpf_program__fd(skel->progs.test3);
+
+ link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
+ if (!ASSERT_GE(link2_fd, 0, "link2_fd"))
+ goto cleanup;
+
+ prog_fd = bpf_program__fd(skel->progs.test1);
+ err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
+ NULL, NULL, &retval, &duration);
+ ASSERT_OK(err, "test_run");
+ ASSERT_EQ(retval, 0, "test_run");
+
+ ASSERT_EQ(skel->bss->test2_result, 8, "test2_result");
+ ASSERT_EQ(skel->bss->test3_result, 8, "test3_result");
+
+cleanup:
+ close(link1_fd);
+ close(link2_fd);
+ fprobe_bpf_cookie__destroy(skel);
+}
+
static void uprobe_subtest(struct test_bpf_cookie *skel)
{
DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts);
@@ -249,6 +320,8 @@ void test_bpf_cookie(void)
if (test__start_subtest("kprobe"))
kprobe_subtest(skel);
+ if (test__start_subtest("rawkprobe"))
+ fprobe_subtest();
if (test__start_subtest("uprobe"))
uprobe_subtest(skel);
if (test__start_subtest("tracepoint"))
diff --git a/tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c b/tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c
new file mode 100644
index 000000000000..42cb109e5a30
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+extern const void bpf_fentry_test1 __ksym;
+extern const void bpf_fentry_test2 __ksym;
+extern const void bpf_fentry_test3 __ksym;
+extern const void bpf_fentry_test4 __ksym;
+extern const void bpf_fentry_test5 __ksym;
+extern const void bpf_fentry_test6 __ksym;
+extern const void bpf_fentry_test7 __ksym;
+extern const void bpf_fentry_test8 __ksym;
+
+/* No tests, just to trigger bpf_fentry_test* through tracing test_run */
+SEC("fentry/bpf_modify_return_test")
+int BPF_PROG(test1)
+{
+ return 0;
+}
+
+__u64 test2_result = 0;
+
+SEC("kprobe/bpf_fentry_test*")
+int test2(struct pt_regs *ctx)
+{
+ __u64 cookie = bpf_get_attach_cookie(ctx);
+ __u64 addr = bpf_get_func_ip(ctx);
+
+ test2_result += (const void *) addr == &bpf_fentry_test1 && cookie == 1;
+ test2_result += (const void *) addr == &bpf_fentry_test2 && cookie == 2;
+ test2_result += (const void *) addr == &bpf_fentry_test3 && cookie == 3;
+ test2_result += (const void *) addr == &bpf_fentry_test4 && cookie == 4;
+ test2_result += (const void *) addr == &bpf_fentry_test5 && cookie == 5;
+ test2_result += (const void *) addr == &bpf_fentry_test6 && cookie == 6;
+ test2_result += (const void *) addr == &bpf_fentry_test7 && cookie == 7;
+ test2_result += (const void *) addr == &bpf_fentry_test8 && cookie == 8;
+
+ return 0;
+}
+
+__u64 test3_result = 0;
+
+SEC("kretprobe/bpf_fentry_test*")
+int test3(struct pt_regs *ctx)
+{
+ __u64 cookie = bpf_get_attach_cookie(ctx);
+ __u64 addr = bpf_get_func_ip(ctx);
+
+ test3_result += (const void *) addr == &bpf_fentry_test1 && cookie == 8;
+ test3_result += (const void *) addr == &bpf_fentry_test2 && cookie == 7;
+ test3_result += (const void *) addr == &bpf_fentry_test3 && cookie == 6;
+ test3_result += (const void *) addr == &bpf_fentry_test4 && cookie == 5;
+ test3_result += (const void *) addr == &bpf_fentry_test5 && cookie == 4;
+ test3_result += (const void *) addr == &bpf_fentry_test6 && cookie == 3;
+ test3_result += (const void *) addr == &bpf_fentry_test7 && cookie == 2;
+ test3_result += (const void *) addr == &bpf_fentry_test8 && cookie == 1;
+
+ return 0;
+}
--
2.34.1
On Wed, Feb 2, 2022 at 5:54 AM Jiri Olsa <[email protected]> wrote:
>
> Adding bpf_cookie test for kprobe attached by fprobe link.
>
> Signed-off-by: Jiri Olsa <[email protected]>
> ---
> .../selftests/bpf/prog_tests/bpf_cookie.c | 73 +++++++++++++++++++
> .../selftests/bpf/progs/fprobe_bpf_cookie.c | 62 ++++++++++++++++
> 2 files changed, 135 insertions(+)
> create mode 100644 tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c
>
> diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> index cd10df6cd0fc..bf70d859c598 100644
> --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> @@ -7,6 +7,7 @@
> #include <unistd.h>
> #include <test_progs.h>
> #include "test_bpf_cookie.skel.h"
> +#include "fprobe_bpf_cookie.skel.h"
>
> /* uprobe attach point */
> static void trigger_func(void)
> @@ -63,6 +64,76 @@ static void kprobe_subtest(struct test_bpf_cookie *skel)
> bpf_link__destroy(retlink2);
> }
>
> +static void fprobe_subtest(void)
> +{
> + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
> + int err, prog_fd, link1_fd = -1, link2_fd = -1;
> + struct fprobe_bpf_cookie *skel = NULL;
> + __u32 duration = 0, retval;
> + __u64 addrs[8], cookies[8];
> +
> + skel = fprobe_bpf_cookie__open_and_load();
> + if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
> + goto cleanup;
> +
> + kallsyms_find("bpf_fentry_test1", &addrs[0]);
> + kallsyms_find("bpf_fentry_test2", &addrs[1]);
> + kallsyms_find("bpf_fentry_test3", &addrs[2]);
> + kallsyms_find("bpf_fentry_test4", &addrs[3]);
> + kallsyms_find("bpf_fentry_test5", &addrs[4]);
> + kallsyms_find("bpf_fentry_test6", &addrs[5]);
> + kallsyms_find("bpf_fentry_test7", &addrs[6]);
> + kallsyms_find("bpf_fentry_test8", &addrs[7]);
> +
> + cookies[0] = 1;
> + cookies[1] = 2;
> + cookies[2] = 3;
> + cookies[3] = 4;
> + cookies[4] = 5;
> + cookies[5] = 6;
> + cookies[6] = 7;
> + cookies[7] = 8;
> +
> + opts.fprobe.addrs = (__u64) &addrs;
we should have ptr_to_u64() for test_progs, but if not, let's either
add it or it should be (__u64)(uintptr_t)&addrs. Otherwise we'll be
getting compilation warnings on some architectures.
> + opts.fprobe.cnt = 8;
> + opts.fprobe.bpf_cookies = (__u64) &cookies;
> + prog_fd = bpf_program__fd(skel->progs.test2);
> +
> + link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
> + if (!ASSERT_GE(link1_fd, 0, "link1_fd"))
> + return;
> +
> + cookies[0] = 8;
> + cookies[1] = 7;
> + cookies[2] = 6;
> + cookies[3] = 5;
> + cookies[4] = 4;
> + cookies[5] = 3;
> + cookies[6] = 2;
> + cookies[7] = 1;
> +
> + opts.flags = BPF_F_FPROBE_RETURN;
> + prog_fd = bpf_program__fd(skel->progs.test3);
> +
> + link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
> + if (!ASSERT_GE(link2_fd, 0, "link2_fd"))
> + goto cleanup;
> +
> + prog_fd = bpf_program__fd(skel->progs.test1);
> + err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
> + NULL, NULL, &retval, &duration);
> + ASSERT_OK(err, "test_run");
> + ASSERT_EQ(retval, 0, "test_run");
> +
> + ASSERT_EQ(skel->bss->test2_result, 8, "test2_result");
> + ASSERT_EQ(skel->bss->test3_result, 8, "test3_result");
> +
> +cleanup:
> + close(link1_fd);
> + close(link2_fd);
> + fprobe_bpf_cookie__destroy(skel);
> +}
> +
> static void uprobe_subtest(struct test_bpf_cookie *skel)
> {
> DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts);
> @@ -249,6 +320,8 @@ void test_bpf_cookie(void)
>
> if (test__start_subtest("kprobe"))
> kprobe_subtest(skel);
> + if (test__start_subtest("rawkprobe"))
kprobe.multi?
> + fprobe_subtest();
> if (test__start_subtest("uprobe"))
> uprobe_subtest(skel);
> if (test__start_subtest("tracepoint"))
[...]
On Mon, Feb 07, 2022 at 10:59:32AM -0800, Andrii Nakryiko wrote:
> On Wed, Feb 2, 2022 at 5:54 AM Jiri Olsa <[email protected]> wrote:
> >
> > Adding bpf_cookie test for kprobe attached by fprobe link.
> >
> > Signed-off-by: Jiri Olsa <[email protected]>
> > ---
> > .../selftests/bpf/prog_tests/bpf_cookie.c | 73 +++++++++++++++++++
> > .../selftests/bpf/progs/fprobe_bpf_cookie.c | 62 ++++++++++++++++
> > 2 files changed, 135 insertions(+)
> > create mode 100644 tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c
> >
> > diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > index cd10df6cd0fc..bf70d859c598 100644
> > --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > @@ -7,6 +7,7 @@
> > #include <unistd.h>
> > #include <test_progs.h>
> > #include "test_bpf_cookie.skel.h"
> > +#include "fprobe_bpf_cookie.skel.h"
> >
> > /* uprobe attach point */
> > static void trigger_func(void)
> > @@ -63,6 +64,76 @@ static void kprobe_subtest(struct test_bpf_cookie *skel)
> > bpf_link__destroy(retlink2);
> > }
> >
> > +static void fprobe_subtest(void)
> > +{
> > + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
> > + int err, prog_fd, link1_fd = -1, link2_fd = -1;
> > + struct fprobe_bpf_cookie *skel = NULL;
> > + __u32 duration = 0, retval;
> > + __u64 addrs[8], cookies[8];
> > +
> > + skel = fprobe_bpf_cookie__open_and_load();
> > + if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
> > + goto cleanup;
> > +
> > + kallsyms_find("bpf_fentry_test1", &addrs[0]);
> > + kallsyms_find("bpf_fentry_test2", &addrs[1]);
> > + kallsyms_find("bpf_fentry_test3", &addrs[2]);
> > + kallsyms_find("bpf_fentry_test4", &addrs[3]);
> > + kallsyms_find("bpf_fentry_test5", &addrs[4]);
> > + kallsyms_find("bpf_fentry_test6", &addrs[5]);
> > + kallsyms_find("bpf_fentry_test7", &addrs[6]);
> > + kallsyms_find("bpf_fentry_test8", &addrs[7]);
> > +
> > + cookies[0] = 1;
> > + cookies[1] = 2;
> > + cookies[2] = 3;
> > + cookies[3] = 4;
> > + cookies[4] = 5;
> > + cookies[5] = 6;
> > + cookies[6] = 7;
> > + cookies[7] = 8;
> > +
> > + opts.fprobe.addrs = (__u64) &addrs;
>
> we should have ptr_to_u64() for test_progs, but if not, let's either
> add it or it should be (__u64)(uintptr_t)&addrs. Otherwise we'll be
> getting compilation warnings on some architectures.
there's one in btf.c, bpf.c and libbpf.c ;-) so I guess it could go to bpf.h
>
> > + opts.fprobe.cnt = 8;
> > + opts.fprobe.bpf_cookies = (__u64) &cookies;
> > + prog_fd = bpf_program__fd(skel->progs.test2);
> > +
> > + link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
> > + if (!ASSERT_GE(link1_fd, 0, "link1_fd"))
> > + return;
> > +
> > + cookies[0] = 8;
> > + cookies[1] = 7;
> > + cookies[2] = 6;
> > + cookies[3] = 5;
> > + cookies[4] = 4;
> > + cookies[5] = 3;
> > + cookies[6] = 2;
> > + cookies[7] = 1;
> > +
> > + opts.flags = BPF_F_FPROBE_RETURN;
> > + prog_fd = bpf_program__fd(skel->progs.test3);
> > +
> > + link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
> > + if (!ASSERT_GE(link2_fd, 0, "link2_fd"))
> > + goto cleanup;
> > +
> > + prog_fd = bpf_program__fd(skel->progs.test1);
> > + err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
> > + NULL, NULL, &retval, &duration);
> > + ASSERT_OK(err, "test_run");
> > + ASSERT_EQ(retval, 0, "test_run");
> > +
> > + ASSERT_EQ(skel->bss->test2_result, 8, "test2_result");
> > + ASSERT_EQ(skel->bss->test3_result, 8, "test3_result");
> > +
> > +cleanup:
> > + close(link1_fd);
> > + close(link2_fd);
> > + fprobe_bpf_cookie__destroy(skel);
> > +}
> > +
> > static void uprobe_subtest(struct test_bpf_cookie *skel)
> > {
> > DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts);
> > @@ -249,6 +320,8 @@ void test_bpf_cookie(void)
> >
> > if (test__start_subtest("kprobe"))
> > kprobe_subtest(skel);
> > + if (test__start_subtest("rawkprobe"))
>
> kprobe.multi?
yes
thanks,
jirka
On Tue, Feb 8, 2022 at 1:16 AM Jiri Olsa <[email protected]> wrote:
>
> On Mon, Feb 07, 2022 at 10:59:32AM -0800, Andrii Nakryiko wrote:
> > On Wed, Feb 2, 2022 at 5:54 AM Jiri Olsa <[email protected]> wrote:
> > >
> > > Adding bpf_cookie test for kprobe attached by fprobe link.
> > >
> > > Signed-off-by: Jiri Olsa <[email protected]>
> > > ---
> > > .../selftests/bpf/prog_tests/bpf_cookie.c | 73 +++++++++++++++++++
> > > .../selftests/bpf/progs/fprobe_bpf_cookie.c | 62 ++++++++++++++++
> > > 2 files changed, 135 insertions(+)
> > > create mode 100644 tools/testing/selftests/bpf/progs/fprobe_bpf_cookie.c
> > >
> > > diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > > index cd10df6cd0fc..bf70d859c598 100644
> > > --- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > > +++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
> > > @@ -7,6 +7,7 @@
> > > #include <unistd.h>
> > > #include <test_progs.h>
> > > #include "test_bpf_cookie.skel.h"
> > > +#include "fprobe_bpf_cookie.skel.h"
> > >
> > > /* uprobe attach point */
> > > static void trigger_func(void)
> > > @@ -63,6 +64,76 @@ static void kprobe_subtest(struct test_bpf_cookie *skel)
> > > bpf_link__destroy(retlink2);
> > > }
> > >
> > > +static void fprobe_subtest(void)
> > > +{
> > > + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
> > > + int err, prog_fd, link1_fd = -1, link2_fd = -1;
> > > + struct fprobe_bpf_cookie *skel = NULL;
> > > + __u32 duration = 0, retval;
> > > + __u64 addrs[8], cookies[8];
> > > +
> > > + skel = fprobe_bpf_cookie__open_and_load();
> > > + if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
> > > + goto cleanup;
> > > +
> > > + kallsyms_find("bpf_fentry_test1", &addrs[0]);
> > > + kallsyms_find("bpf_fentry_test2", &addrs[1]);
> > > + kallsyms_find("bpf_fentry_test3", &addrs[2]);
> > > + kallsyms_find("bpf_fentry_test4", &addrs[3]);
> > > + kallsyms_find("bpf_fentry_test5", &addrs[4]);
> > > + kallsyms_find("bpf_fentry_test6", &addrs[5]);
> > > + kallsyms_find("bpf_fentry_test7", &addrs[6]);
> > > + kallsyms_find("bpf_fentry_test8", &addrs[7]);
> > > +
> > > + cookies[0] = 1;
> > > + cookies[1] = 2;
> > > + cookies[2] = 3;
> > > + cookies[3] = 4;
> > > + cookies[4] = 5;
> > > + cookies[5] = 6;
> > > + cookies[6] = 7;
> > > + cookies[7] = 8;
> > > +
> > > + opts.fprobe.addrs = (__u64) &addrs;
> >
> > we should have ptr_to_u64() for test_progs, but if not, let's either
> > add it or it should be (__u64)(uintptr_t)&addrs. Otherwise we'll be
> > getting compilation warnings on some architectures.
>
> there's one in btf.c, bpf.c and libbpf.c ;-) so I guess it could go to bpf.h
No, it shouldn't, bpf.h is a public API header. Let's keep internal
helpers internal. Just copy/paste.
>
> >
> > > + opts.fprobe.cnt = 8;
> > > + opts.fprobe.bpf_cookies = (__u64) &cookies;
> > > + prog_fd = bpf_program__fd(skel->progs.test2);
> > > +
> > > + link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
> > > + if (!ASSERT_GE(link1_fd, 0, "link1_fd"))
> > > + return;
> > > +
> > > + cookies[0] = 8;
> > > + cookies[1] = 7;
> > > + cookies[2] = 6;
> > > + cookies[3] = 5;
> > > + cookies[4] = 4;
> > > + cookies[5] = 3;
> > > + cookies[6] = 2;
> > > + cookies[7] = 1;
> > > +
> > > + opts.flags = BPF_F_FPROBE_RETURN;
> > > + prog_fd = bpf_program__fd(skel->progs.test3);
> > > +
> > > + link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_FPROBE, &opts);
> > > + if (!ASSERT_GE(link2_fd, 0, "link2_fd"))
> > > + goto cleanup;
> > > +
> > > + prog_fd = bpf_program__fd(skel->progs.test1);
> > > + err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
> > > + NULL, NULL, &retval, &duration);
> > > + ASSERT_OK(err, "test_run");
> > > + ASSERT_EQ(retval, 0, "test_run");
> > > +
> > > + ASSERT_EQ(skel->bss->test2_result, 8, "test2_result");
> > > + ASSERT_EQ(skel->bss->test3_result, 8, "test3_result");
> > > +
> > > +cleanup:
> > > + close(link1_fd);
> > > + close(link2_fd);
> > > + fprobe_bpf_cookie__destroy(skel);
> > > +}
> > > +
> > > static void uprobe_subtest(struct test_bpf_cookie *skel)
> > > {
> > > DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts);
> > > @@ -249,6 +320,8 @@ void test_bpf_cookie(void)
> > >
> > > if (test__start_subtest("kprobe"))
> > > kprobe_subtest(skel);
> > > + if (test__start_subtest("rawkprobe"))
> >
> > kprobe.multi?
>
> yes
>
> thanks,
> jirka
>