Gracefully skip test if userfaultfd is not supported (ENOSYS) or not
permitted (EPERM), instead of failing.  This avoids misleading failures
with clear skip messages.

--------------
Before Patch
--------------
~ running ./hugepage-mremap
...
~ Bail out! userfaultfd: Function not implemented
~ Planned tests != run tests (1 != 0)
~ Totals: pass:0 fail:0 xfail:0 xpass:0 skip:0 error:0
~ [FAIL]
not ok 4 hugepage-mremap # exit=1

--------------
After Patch
--------------
~ running ./hugepage-mremap
...
~ ok 2 # SKIP userfaultfd is not supported/not enabled.
~ 1 skipped test(s) detected.
~ Totals: pass:0 fail:0 xfail:0 xpass:0 skip:1 error:0
~ [SKIP]
ok 4 hugepage-mremap # SKIP

Co-developed-by: Donet Tom <donet...@linux.ibm.com>
Signed-off-by: Donet Tom <donet...@linux.ibm.com>
Acked-by: David Hildenbrand <da...@redhat.com>
Reviewed-by: Zi Yan <z...@nvidia.com>
Signed-off-by: Aboorva Devarajan <aboor...@linux.ibm.com>
---
 tools/testing/selftests/mm/hugepage-mremap.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/mm/hugepage-mremap.c 
b/tools/testing/selftests/mm/hugepage-mremap.c
index c463d1c09c9b..2bd1dac75c3f 100644
--- a/tools/testing/selftests/mm/hugepage-mremap.c
+++ b/tools/testing/selftests/mm/hugepage-mremap.c
@@ -65,10 +65,20 @@ static void register_region_with_uffd(char *addr, size_t 
len)
        struct uffdio_api uffdio_api;
 
        /* Create and enable userfaultfd object. */
-
        uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
-       if (uffd == -1)
-               ksft_exit_fail_msg("userfaultfd: %s\n", strerror(errno));
+       if (uffd == -1) {
+               switch (errno) {
+               case EPERM:
+                       ksft_exit_skip("Insufficient permissions, try running 
as root.\n");
+                       break;
+               case ENOSYS:
+                       ksft_exit_skip("userfaultfd is not supported/not 
enabled.\n");
+                       break;
+               default:
+                       ksft_exit_fail_msg("userfaultfd failed with %s\n", 
strerror(errno));
+                       break;
+               }
+       }
 
        uffdio_api.api = UFFD_API;
        uffdio_api.features = 0;
-- 
2.47.1


Reply via email to