From: Alexei Starovoitov <ast@xxxxxxxxxx>
Add light skeleton test for kfunc detection.
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
.../testing/selftests/bpf/progs/test_ksyms_weak.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_weak.c b/tools/testing/selftests/bpf/progs/test_ksyms_weak.c
index 7003eef0c192..d00268c91e19 100644
--- a/tools/testing/selftests/bpf/progs/test_ksyms_weak.c
+++ b/tools/testing/selftests/bpf/progs/test_ksyms_weak.c
@@ -20,6 +20,8 @@ __u64 out__non_existent_typed = -1;
/* test existing weak symbols can be resolved. */
extern const struct rq runqueues __ksym __weak; /* typed */
extern const void bpf_prog_active __ksym __weak; /* typeless */
+struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym __weak;
+void bpf_testmod_test_mod_kfunc(int i) __ksym __weak;
/* non-existent weak symbols. */
@@ -29,6 +31,7 @@ extern const void bpf_link_fops1 __ksym __weak;
/* typed symbols, default to zero. */
extern const int bpf_link_fops2 __ksym __weak;
+void invalid_kfunc(void) __ksym __weak;
SEC("raw_tp/sys_enter")
int pass_handler(const void *ctx)
@@ -50,6 +53,18 @@ int pass_handler(const void *ctx)
if (&bpf_link_fops2) /* can't happen */
out__non_existent_typed = (__u64)bpf_per_cpu_ptr(&bpf_link_fops2, 0);
+ if (!bpf_ksym_exists(bpf_task_acquire))
+ /* dead code won't be seen by the verifier */
+ bpf_task_acquire(0);
+
+ if (!bpf_ksym_exists(bpf_testmod_test_mod_kfunc))
+ /* dead code won't be seen by the verifier */
+ bpf_testmod_test_mod_kfunc(0);
+
+ if (bpf_ksym_exists(invalid_kfunc))
+ /* dead code won't be seen by the verifier */
+ invalid_kfunc();
+
return 0;
}
--
2.34.1
