On 7/24/25 9:34 PM, Yonghong Song wrote:
For arm64 64K page size, the xdp data size was set to be more than 64K
in one of previous patches. This will cause failure for bpf_dynptr_memset().
Since the failure of bpf_dynptr_memset() is expected with 64K page size,
return success.
Signed-off-by: Yonghong Song <yonghong.song@xxxxxxxxx>
---
tools/testing/selftests/bpf/progs/dynptr_success.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/progs/dynptr_success.c b/tools/testing/selftests/bpf/progs/dynptr_success.c
index 3094a1e4ee91..8315273cb900 100644
--- a/tools/testing/selftests/bpf/progs/dynptr_success.c
+++ b/tools/testing/selftests/bpf/progs/dynptr_success.c
@@ -9,6 +9,8 @@
#include "bpf_misc.h"
#include "errno.h"
+#define PAGE_SIZE_64K 65536
+
char _license[] SEC("license") = "GPL";
int pid, err, val;
@@ -821,8 +823,17 @@ int test_dynptr_memset_xdp_chunks(struct xdp_md *xdp)
data_sz = bpf_dynptr_size(&ptr_xdp);
err = bpf_dynptr_memset(&ptr_xdp, 0, data_sz, DYNPTR_MEMSET_VAL);
- if (err)
+ if (err) {
+ /* bpf_dynptr_memset() eventually called bpf_xdp_pointer()
I don't think I understand why the test fixed in patch 1 (e.g.
test_probe_read_user_dynptr) can pass the bpf_xdp_pointer test on 0xffff. I
thought the bpf_probe_read_user_str_dynptr will eventually call the
__bpf_xdp_store_bytes which also does a bpf_xdp_pointer?
+ * where if data_sz is greater than 0xffff, -EFAULT will be
+ * returned. For 64K page size, data_sz is greater than
+ * 64K, so error is expected and let us zero out error and
+ * return success.
+ */
+ if (data_sz >= PAGE_SIZE_64K)
+ err = 0;
goto out;
+ }
bpf_for(i, 0, max_chunks) {
offset = i * sizeof(buf);
