mm: turn off test_uffdio_wp if CONFIG_PTE_MARKER_UFFD_WP is not configured.

commit a591d35
Author: Audra Mitchell <audra@redhat.com>
Date:   Wed Jun 26 09:05:13 2024 -0400

    mm: turn off test_uffdio_wp if CONFIG_PTE_MARKER_UFFD_WP is not configured.

    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.

    Link: https://lkml.kernel.org/r/20240626130513.120193-3-audra@redhat.com
    Signed-off-by: Audra Mitchell <audra@redhat.com>
    Reviewed-by: Peter Xu <peterx@redhat.com>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: Andrea Arcangeli <aarcange@redhat.com>
    Cc: Christian Brauner <brauner@kernel.org>
    Cc: Jan Kara <jack@suse.cz>
    Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
    Cc: Rafael Aquini <raquini@redhat.com>
    Cc: Shaohua Li <shli@fb.com>
    Cc: Shuah Khan <shuah@kernel.org>
    Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

JIRA: https://issues.redhat.com/browse/RHEL-39306
Signed-off-by: Nico Pache <npache@redhat.com>

Author: PacheNico

tools/testing/selftests/mm/uffd-stress.c

@@ -415,6 +415,9 @@ 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;
 }