diff options
| -rw-r--r-- | tools/testing/selftests/vm/userfaultfd.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 6e482e2f198c..9d8650d4ba5a 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -794,7 +794,8 @@ static int userfaultfd_open(int features) uffdio_api.api = UFFD_API; uffdio_api.features = features; if (ioctl(uffd, UFFDIO_API, &uffdio_api)) { - fprintf(stderr, "UFFDIO_API\n"); + fprintf(stderr, "UFFDIO_API failed.\nPlease make sure to " + "run with either root or ptrace capability.\n"); return 1; } if (uffdio_api.api != UFFD_API) { |