mm: update uffd-stress to handle EINVAL for unset config features

Now that we have updated userfaultfd_api to correctly return EINVAL when a
feature is requested but not available, let's fix the uffd-stress test to
only set the UFFD_FEATURE_WP_UNPOPULATED feature when the config is set.
In addition, still run the test if the CONFIG_PTE_MARKER_UFFD_WP is not
set, just dont use the corresponding UFFD_FEATURE_WP_UNPOPULATED feature.

Link: https://lkml.kernel.org/r/20240626130513.120193-2-audra@redhat.com
Signed-off-by: Audra Mitchell <audra@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: Peter Xu <peterx@redhat.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>

diff --git a/tools/testing/selftests/mm/uffd-stress.c b/tools/testing/selftests/mm/uffd-stress.c
index 0abb9af0fc7f35d6cb36183e26f787f16050a8be..cc8e0fd0da1ce14de4a0df1ba76c831d72cd0f82 100644 (file)
--- a/tools/testing/selftests/mm/uffd-stress.c
+++ b/tools/testing/selftests/mm/uffd-stress.c
@@ -36,6 +36,8 @@
 #include <asm-generic/unistd.h>
 #include "uffd-common.h"
 
+uint64_t features;
+
 #define BOUNCE_RANDOM          (1<<0)
 #define BOUNCE_RACINGFAULTS    (1<<1)
 #define BOUNCE_VERIFY          (1<<2)
@@ -245,10 +247,14 @@ static int userfaultfd_stress(void)
        unsigned long nr;
        struct uffd_args args[nr_cpus];
        uint64_t mem_size = nr_pages * page_size;
+       int flags = 0;
 
        memset(args, 0, sizeof(struct uffd_args) * nr_cpus);
 
-       if (uffd_test_ctx_init(UFFD_FEATURE_WP_UNPOPULATED, NULL))
+       if (features & UFFD_FEATURE_WP_UNPOPULATED && test_type == TEST_ANON)
+               flags = UFFD_FEATURE_WP_UNPOPULATED;
+
+       if (uffd_test_ctx_init(flags, NULL))
                err("context init failed");
 
        if (posix_memalign(&area, page_size, page_size))
@@ -383,8 +389,6 @@ static void set_test_type(const char *type)
 
 static void parse_test_type_arg(const char *raw_type)
 {
-       uint64_t features = UFFD_API_FEATURES;
-
        set_test_type(raw_type);
 
        if (!test_type)
@@ -407,8 +411,8 @@ static void parse_test_type_arg(const char *raw_type)
         * feature.
         */
 
-       if (userfaultfd_open(&features))
-               err("Userfaultfd open failed");
+       if (uffd_get_features(&features))
+               err("failed to get available features");
 
        test_uffdio_wp = test_uffdio_wp &&
                (features & UFFD_FEATURE_PAGEFAULT_FLAG_WP);