If CONFIG_PTE_MARKER_UFFD_WP is disabled, then we turn off three features in userfaultfd_api (UFFD_FEATURE_WP_HUGETLBFS_SHMEM, UFFD_FEATURE_WP_UNPOPULATED, and UFFD_FEATURE_WP_ASYNC). Currently this test always will call uffdio_regsiter with the flag UFFDIO_REGISTER_MODE_WP. However, the kernel ensures in vma_can_userfault that if the feature UFFD_FEATURE_WP_HUGETLBFS_SHMEM is disabled, only allow the VM_UFFD_WP on anonymous vmas, meaning our call to uffdio_regsiter will fail. We still want to be able to run the test even if we have CONFIG_PTE_MARKER_UFFD_WP disabled, so check to see if the feature UFFD_FEATURE_WP_HUGETLBFS_SHMEM has been turned off in the test and if so, disable us from calling uffdio_regsiter with the flag UFFDIO_REGISTER_MODE_WP.
Signed-off-by: Audra Mitchell audra@redhat.com --- tools/testing/selftests/mm/uffd-stress.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c index b9b6d858eab8..3266ae885f75 100644 --- a/tools/testing/selftests/mm/uffd-stress.c +++ b/tools/testing/selftests/mm/uffd-stress.c @@ -419,6 +419,9 @@ static void parse_test_type_arg(const char *raw_type) test_uffdio_wp = test_uffdio_wp && (features & UFFD_FEATURE_PAGEFAULT_FLAG_WP);
+ if (test_type != TEST_ANON && !(features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM)) + test_uffdio_wp = false; + close(uffd); uffd = -1; }