kselftest/arm64: Check that unsupported regsets fail in sve-ptrace

Add a test which verifies that NT_ARM_SVE and NT_ARM_SSVE reads and writes
are rejected as expected when the relevant architecture feature is not
supported.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/tools/testing/selftests/arm64/fp/sve-ptrace.c b/tools/testing/selftests/arm64/fp/sve-ptrace.c
index 0ce841a7bb6ee6a27f8c965543211bd3b61c8e3e..e0fc3a001e2830759dee2860074beb3d1b380775 100644 (file)
--- a/tools/testing/selftests/arm64/fp/sve-ptrace.c
+++ b/tools/testing/selftests/arm64/fp/sve-ptrace.c
@@ -174,6 +174,38 @@ static int set_sve(pid_t pid, const struct vec_type *type,
        return ret;
 }
 
+/* A read operation fails */
+static void read_fails(pid_t child, const struct vec_type *type)
+{
+       struct user_sve_header *new_sve = NULL;
+       size_t new_sve_size = 0;
+       void *ret;
+
+       ret = get_sve(child, type, (void **)&new_sve, &new_sve_size);
+
+       ksft_test_result(ret == NULL, "%s unsupported read fails\n",
+                        type->name);
+
+       free(new_sve);
+}
+
+/* A write operation fails */
+static void write_fails(pid_t child, const struct vec_type *type)
+{
+       struct user_sve_header sve;
+       int ret;
+
+       /* Just the header, no data */
+       memset(&sve, 0, sizeof(sve));
+       sve.size = sizeof(sve);
+       sve.flags = SVE_PT_REGS_SVE;
+       sve.vl = SVE_VL_MIN;
+       ret = set_sve(child, type, &sve);
+
+       ksft_test_result(ret != 0, "%s unsupported write fails\n",
+                        type->name);
+}
+
 /* Validate setting and getting the inherit flag */
 static void ptrace_set_get_inherit(pid_t child, const struct vec_type *type)
 {
@@ -718,6 +750,20 @@ static int do_parent(pid_t child)
        }
 
        for (i = 0; i < ARRAY_SIZE(vec_types); i++) {
+               /*
+                * If the vector type isn't supported reads and writes
+                * should fail.
+                */
+               if (!(getauxval(vec_types[i].hwcap_type) & vec_types[i].hwcap)) {
+                       read_fails(child, &vec_types[i]);
+                       write_fails(child, &vec_types[i]);
+               } else {
+                       ksft_test_result_skip("%s unsupported read fails\n",
+                                             vec_types[i].name);
+                       ksft_test_result_skip("%s unsupported write fails\n",
+                                             vec_types[i].name);
+               }
+
                /* FPSIMD via SVE regset */
                if (getauxval(vec_types[i].hwcap_type) & vec_types[i].hwcap) {
                        ptrace_sve_fpsimd(child, &vec_types[i]);