The issue has been fixed on both x64 and arm64.
On x64:
cd tools/testing/selftests/bpf; ./test_progs -t tailcalls
334/26 tailcalls/tailcall_bpf2bpf_freplace:OK
334/27 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_1:OK
334/28 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_2:OK
334/29 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_3:OK
334/30 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_4:OK
334/31 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_5:OK
334 tailcalls:OK
Summary: 1/31 PASSED, 0 SKIPPED, 0 FAILED
on arm64:
cd tools/testing/selftests/bpf; ./test_progs -t tailcalls
334/26 tailcalls/tailcall_bpf2bpf_freplace:OK
334/27 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_1:OK
334/28 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_2:OK
334/29 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_3:OK
334/30 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_4:OK
334/31 tailcalls/tailcall_bpf2bpf_hierarchy_freplace_5:OK
334 tailcalls:OK
Summary: 1/31 PASSED, 0 SKIPPED, 0 FAILED
Signed-off-by: Leon Hwang <leon.hwang@xxxxxxxxx>
---
.../selftests/bpf/prog_tests/tailcalls.c | 216 +++++++++++++++++-
.../tailcall_bpf2bpf_hierarchy_freplace.c | 30 +++
.../testing/selftests/bpf/progs/tc_bpf2bpf.c | 37 ++-
3 files changed, 279 insertions(+), 4 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_hierarchy_freplace.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tailcalls.c b/tools/testing/selftests/bpf/prog_tests/tailcalls.c
index 21c5a37846ade..0faa0f57f71d4 100644
--- a/tools/testing/selftests/bpf/prog_tests/tailcalls.c
+++ b/tools/testing/selftests/bpf/prog_tests/tailcalls.c
@@ -5,6 +5,7 @@
#include "tailcall_poke.skel.h"
#include "tailcall_bpf2bpf_hierarchy2.skel.h"
#include "tailcall_bpf2bpf_hierarchy3.skel.h"
+#include "tailcall_bpf2bpf_hierarchy_freplace.skel.h"
#include "tailcall_freplace.skel.h"
#include "tc_bpf2bpf.skel.h"
@@ -1525,7 +1526,8 @@ static void test_tailcall_freplace(void)
prog_fd = bpf_program__fd(tc_skel->progs.entry_tc);
freplace_prog = freplace_skel->progs.entry_freplace;
- err = bpf_program__set_attach_target(freplace_prog, prog_fd, "subprog");
+ err = bpf_program__set_attach_target(freplace_prog, prog_fd,
+ "subprog_tailcall_tc");
if (!ASSERT_OK(err, "set_attach_target"))
goto out;
@@ -1534,7 +1536,7 @@ static void test_tailcall_freplace(void)
goto out;
freplace_link = bpf_program__attach_freplace(freplace_prog, prog_fd,
- "subprog");
+ "subprog_tailcall_tc");
if (!ASSERT_OK_PTR(freplace_link, "attach_freplace"))
goto out;
@@ -1556,6 +1558,204 @@ static void test_tailcall_freplace(void)
tailcall_freplace__destroy(freplace_skel);
}
+/* test_tailcall_bpf2bpf_freplace checks that the count value of the tail
+ * call limit enforcement matches with expectation for this case:
+ *
+ * entry_tc --> subprog_tailcall_tc --jump-> entry_freplace --tailcall-> entry_tc
+ *
+ * Meanwhile, check the failure that fails to attach tailcall-reachable freplace
+ * prog to not-tailcall-reachable subprog.
+ */
+static void test_tailcall_bpf2bpf_freplace(void)
+{
+ struct tailcall_freplace *freplace_skel = NULL;
+ struct bpf_link *freplace_link = NULL;
+ struct tc_bpf2bpf *tc_skel = NULL;
+ char buff[128] = {};
+ int prog_fd, map_fd;
+ int err, i;
+
+ LIBBPF_OPTS(bpf_test_run_opts, topts,
+ .data_in = buff,
+ .data_size_in = sizeof(buff),
+ .repeat = 1,
+ );
+
+ tc_skel = tc_bpf2bpf__open_and_load();
+ if (!ASSERT_OK_PTR(tc_skel, "tc_bpf2bpf__open_and_load"))
+ goto out;
+
+ prog_fd = bpf_program__fd(tc_skel->progs.entry_tc);
+ freplace_skel = tailcall_freplace__open();
+ if (!ASSERT_OK_PTR(freplace_skel, "tailcall_freplace__open"))
+ goto out;
+
+ err = bpf_program__set_attach_target(freplace_skel->progs.entry_freplace,
+ prog_fd, "subprog_tailcall_tc");
+ if (!ASSERT_OK(err, "set_attach_target"))
+ goto out;
+
+ err = tailcall_freplace__load(freplace_skel);
+ if (!ASSERT_OK(err, "tailcall_freplace__load"))
+ goto out;
+
+ i = 0;
+ map_fd = bpf_map__fd(freplace_skel->maps.jmp_table);
+ err = bpf_map_update_elem(map_fd, &i, &prog_fd, BPF_ANY);
+ if (!ASSERT_OK(err, "update jmp_table"))
+ goto out;
+
+ freplace_link = bpf_program__attach_freplace(freplace_skel->progs.entry_freplace,
+ prog_fd, "subprog_tc");
+ if (!ASSERT_ERR_PTR(freplace_link, "attach_freplace fail"))
+ goto out;
+
+ freplace_link = bpf_program__attach_freplace(freplace_skel->progs.entry_freplace,
+ prog_fd, "subprog_tailcall_tc");
+ if (!ASSERT_OK_PTR(freplace_link, "attach_freplace"))
+ goto out;
+
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run_opts");
+ ASSERT_EQ(topts.retval, 34, "test_run_opts retval");
+
+out:
+ bpf_link__destroy(freplace_link);
+ tailcall_freplace__destroy(freplace_skel);
+ tc_bpf2bpf__destroy(tc_skel);
+}
+
+static void test_tailcall_bpf2bpf_hierarchy_freplace(bool freplace_subprog,
+ bool tailcall_tc,
+ bool target_entry2,
+ int count1, int count2)
+{
+ struct tailcall_bpf2bpf_hierarchy_freplace *freplace_skel = NULL;
+ struct bpf_link *freplace_link = NULL;
+ int freplace_prog_fd, prog_fd, map_fd;
+ struct tc_bpf2bpf *tc_skel = NULL;
+ char buff[128] = {};
+ int err, i, val;
+
+ LIBBPF_OPTS(bpf_test_run_opts, topts,
+ .data_in = buff,
+ .data_size_in = sizeof(buff),
+ .repeat = 1,
+ );
+
+ tc_skel = tc_bpf2bpf__open_and_load();
+ if (!ASSERT_OK_PTR(tc_skel, "tc_bpf2bpf__open_and_load"))
+ goto out;
+
+ prog_fd = bpf_program__fd(target_entry2 ? tc_skel->progs.entry_tc_2 :
+ tc_skel->progs.entry_tc);
+ freplace_skel = tailcall_bpf2bpf_hierarchy_freplace__open();
+ if (!ASSERT_OK_PTR(freplace_skel, "tailcall_bpf2bpf_hierarchy_freplace__open"))
+ goto out;
+
+ err = bpf_program__set_attach_target(freplace_skel->progs.entry_freplace,
+ prog_fd, freplace_subprog ?
+ "subprog_tailcall_tc" : "entry_tc");
+ if (!ASSERT_OK(err, "set_attach_target"))
+ goto out;
+
+ err = tailcall_bpf2bpf_hierarchy_freplace__load(freplace_skel);
+ if (!ASSERT_OK(err, "tailcall_bpf2bpf_hierarchy_freplace__load"))
+ goto out;
+
+ freplace_prog_fd = bpf_program__fd(freplace_skel->progs.entry_freplace);
+ map_fd = bpf_map__fd(freplace_skel->maps.jmp_table);
+ val = tailcall_tc ? prog_fd : freplace_prog_fd;
+ i = 0;
+ err = bpf_map_update_elem(map_fd, &i, &val, BPF_ANY);
+ if (!ASSERT_OK(err, "update jmp_table"))
+ goto out;
+
+ freplace_link = bpf_program__attach_freplace(freplace_skel->progs.entry_freplace,
+ prog_fd, freplace_subprog ?
+ "subprog_tailcall_tc" : "entry_tc");
+ if (!ASSERT_OK_PTR(freplace_link, "attach_freplace"))
+ goto out;
+
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run_opts");
+ ASSERT_EQ(topts.retval, count1, "test_run_opts retval");
+
+ i = 0;
+ err = bpf_map_delete_elem(map_fd, &i);
+ if (!ASSERT_OK(err, "delete_elem from jmp_table"))
+ goto out;
+
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run_opts again");
+ ASSERT_EQ(topts.retval, count2, "test_run_opts retval again");
+
+out:
+ bpf_link__destroy(freplace_link);
+ tailcall_bpf2bpf_hierarchy_freplace__destroy(freplace_skel);
+ tc_bpf2bpf__destroy(tc_skel);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_freplace_1 checks the count value of tail
+ * call limit enforcement matches with expectation for this case:
+ *
+ * subprog_tail --tailcall-> entry_freplace
+ * entry_tc --jump-> entry_freplace <
+ * subprog_tail --tailcall-> entry_freplace
+ */
+static void test_tailcall_bpf2bpf_hierarchy_freplace_1(void)
+{
+ test_tailcall_bpf2bpf_hierarchy_freplace(false, false, false, 34, 35);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_freplace_2 checks the count value of tail
+ * call limit enforcement matches with expectation for this case:
+ *
+ * subprog_tail --tailcall-> entry_freplace
+ * entry_tc --> subprog_tailcall_tc --jump-> entry_freplace <
+ * subprog_tail --tailcall-> entry_freplace
+ */
+static void test_tailcall_bpf2bpf_hierarchy_freplace_2(void)
+{
+ test_tailcall_bpf2bpf_hierarchy_freplace(true, false, false, 34, 35);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_freplace_3 checks the count value of tail
+ * call limit enforcement matches with expectation for this case:
+ *
+ * subprog_tail --tailcall-> entry_tc
+ * entry_tc --> subprog_tailcall_tc --jump-> entry_freplace <
+ * subprog_tail --tailcall-> entry_tc
+ */
+static void test_tailcall_bpf2bpf_hierarchy_freplace_3(void)
+{
+ test_tailcall_bpf2bpf_hierarchy_freplace(true, true, false, 34, 35);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_freplace_4 checks the count value of tail
+ * call limit enforcement matches with expectation for this case:
+ *
+ * subprog_tail --tailcall-> entry_freplace
+ * entry_tc_2 --> subprog_tailcall_tc (call 10 times) --jump-> entry_freplace <
+ * subprog_tail --tailcall-> entry_freplace
+ */
+static void test_tailcall_bpf2bpf_hierarchy_freplace_4(void)
+{
+ test_tailcall_bpf2bpf_hierarchy_freplace(true, false, true, 43, 53);
+}
+
+/* test_tailcall_bpf2bpf_hierarchy_freplace_5 checks the count value of tail
+ * call limit enforcement matches with expectation for this case:
+ *
+ * subprog_tail --tailcall-> entry_tc_2
+ * entry_tc_2 --> subprog_tailcall_tc (call 10 times) --jump-> entry_freplace <
+ * subprog_tail --tailcall-> entry_tc_2
+ */
+static void test_tailcall_bpf2bpf_hierarchy_freplace_5(void)
+{
+ test_tailcall_bpf2bpf_hierarchy_freplace(true, true, true, 340, 350);
+}
+
void test_tailcalls(void)
{
if (test__start_subtest("tailcall_1"))
@@ -1606,4 +1806,16 @@ void test_tailcalls(void)
test_tailcall_bpf2bpf_hierarchy_3();
if (test__start_subtest("tailcall_freplace"))
test_tailcall_freplace();
+ if (test__start_subtest("tailcall_bpf2bpf_freplace"))
+ test_tailcall_bpf2bpf_freplace();
+ if (test__start_subtest("tailcall_bpf2bpf_hierarchy_freplace_1"))
+ test_tailcall_bpf2bpf_hierarchy_freplace_1();
+ if (test__start_subtest("tailcall_bpf2bpf_hierarchy_freplace_2"))
+ test_tailcall_bpf2bpf_hierarchy_freplace_2();
+ if (test__start_subtest("tailcall_bpf2bpf_hierarchy_freplace_3"))
+ test_tailcall_bpf2bpf_hierarchy_freplace_3();
+ if (test__start_subtest("tailcall_bpf2bpf_hierarchy_freplace_4"))
+ test_tailcall_bpf2bpf_hierarchy_freplace_4();
+ if (test__start_subtest("tailcall_bpf2bpf_hierarchy_freplace_5"))
+ test_tailcall_bpf2bpf_hierarchy_freplace_5();
}
diff --git a/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_hierarchy_freplace.c b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_hierarchy_freplace.c
new file mode 100644
index 0000000000000..6f7c1fac9ddb7
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tailcall_bpf2bpf_hierarchy_freplace.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 1);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+int count = 0;
+
+static __noinline
+int subprog_tail(struct __sk_buff *skb)
+{
+ bpf_tail_call_static(skb, &jmp_table, 0);
+ return 0;
+}
+
+SEC("freplace")
+int entry_freplace(struct __sk_buff *skb)
+{
+ count++;
+ subprog_tail(skb);
+ subprog_tail(skb);
+ return count;
+}
+
+char __license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c
index 8a0632c37839a..beacf60a52677 100644
--- a/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c
+++ b/tools/testing/selftests/bpf/progs/tc_bpf2bpf.c
@@ -4,11 +4,30 @@
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
+struct {
+ __uint(type, BPF_MAP_TYPE_PROG_ARRAY);
+ __uint(max_entries, 1);
+ __uint(key_size, sizeof(__u32));
+ __uint(value_size, sizeof(__u32));
+} jmp_table SEC(".maps");
+
+__noinline
+int subprog_tailcall_tc(struct __sk_buff *skb)
+{
+ int ret = 1;
+
+ bpf_tail_call_static(skb, &jmp_table, 0);
+ __sink(skb);
+ __sink(ret);
+ return ret;
+}
+
__noinline
-int subprog(struct __sk_buff *skb)
+int subprog_tc(struct __sk_buff *skb)
{
int ret = 1;
+ __sink(skb);
__sink(ret);
return ret;
}
@@ -16,7 +35,21 @@ int subprog(struct __sk_buff *skb)
SEC("tc")
int entry_tc(struct __sk_buff *skb)
{
- return subprog(skb);
+ subprog_tc(skb);
+ return subprog_tailcall_tc(skb);
+}
+
+SEC("tc")
+int entry_tc_2(struct __sk_buff *skb)
+{
+ int ret, i;
+
+ for (i = 0; i < 10; i++) {
+ ret = subprog_tailcall_tc(skb);
+ __sink(ret);
+ }
+
+ return ret;
}
char __license[] SEC("license") = "GPL";
--
2.44.0
