tests/qtest: Fix tests when no KVM or TCG are present

It is possible to have a build with both TCG and KVM disabled due to
Xen requiring the i386 and x86_64 binaries to be present in an aarch64
host.

If we build with --disable-tcg on the aarch64 host, we will end-up
with a QEMU binary (x86) that does not support TCG nor KVM.

Skip tests that crash or hang in the above scenario. Do not include
any test cases if TCG and KVM are missing.

Make sure that calls to qtest_has_accel are placed after g_test_init
in similar fashion to commit ae4b01b ("tests: Ensure TAP version is
printed before other messages") to avoid TAP parsing errors.

Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20230426180013.14814-9-farosas@suse.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

tests/qtest/bios-tables-test.c

@@ -2045,8 +2045,7 @@ static void test_acpi_virt_oem_fields(void)
 int main(int argc, char *argv[])
 {
     const char *arch = qtest_get_arch();
-    const bool has_kvm = qtest_has_accel("kvm");
-    const bool has_tcg = qtest_has_accel("tcg");
+    bool has_kvm, has_tcg;
     char *v_env = getenv("V");
     int ret;
 
@@ -2056,6 +2055,14 @@ int main(int argc, char *argv[])
 
     g_test_init(&argc, &argv, NULL);
 
+    has_kvm = qtest_has_accel("kvm");
+    has_tcg = qtest_has_accel("tcg");
+
+    if (!has_tcg && !has_kvm) {
+        g_test_skip("No KVM or TCG accelerator available");
+        return 0;
+    }
+
     if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
         ret = boot_sector_init(disk);
         if (ret) {

tests/qtest/boot-serial-test.c

@@ -287,6 +287,11 @@ int main(int argc, char *argv[])
 
     g_test_init(&argc, &argv, NULL);
 
+    if (!qtest_has_accel("tcg") && !qtest_has_accel("kvm")) {
+        g_test_skip("No KVM or TCG accelerator available");
+        return 0;
+    }
+
     for (i = 0; tests[i].arch != NULL; i++) {
         if (g_str_equal(arch, tests[i].arch) &&
             qtest_has_machine(tests[i].machine)) {

tests/qtest/migration-test.c

@@ -2477,7 +2477,7 @@ static bool kvm_dirty_ring_supported(void)
 
 int main(int argc, char **argv)
 {
-    bool has_kvm;
+    bool has_kvm, has_tcg;
     bool has_uffd;
     const char *arch;
     g_autoptr(GError) err = NULL;
@@ -2486,6 +2486,13 @@ int main(int argc, char **argv)
     g_test_init(&argc, &argv, NULL);
 
     has_kvm = qtest_has_accel("kvm");
+    has_tcg = qtest_has_accel("tcg");
+
+    if (!has_tcg && !has_kvm) {
+        g_test_skip("No KVM or TCG accelerator available");
+        return 0;
+    }
+
     has_uffd = ufd_version_check();
     arch = qtest_get_arch();
 

tests/qtest/pxe-test.c

@@ -131,11 +131,17 @@ int main(int argc, char *argv[])
     int ret;
     const char *arch = qtest_get_arch();
 
+    g_test_init(&argc, &argv, NULL);
+
+    if (!qtest_has_accel("tcg") && !qtest_has_accel("kvm")) {
+        g_test_skip("No KVM or TCG accelerator available");
+        return 0;
+    }
+
     ret = boot_sector_init(disk);
     if(ret)
         return ret;
 
-    g_test_init(&argc, &argv, NULL);
 
     if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) {
         test_batch(x86_tests, false);

tests/qtest/vmgenid-test.c

@@ -165,13 +165,18 @@ int main(int argc, char **argv)
 {
     int ret;
 
+    g_test_init(&argc, &argv, NULL);
+
+    if (!qtest_has_accel("tcg") && !qtest_has_accel("kvm")) {
+        g_test_skip("No KVM or TCG accelerator available");
+        return 0;
+    }
+
     ret = boot_sector_init(disk);
     if (ret) {
         return ret;
     }
 
-    g_test_init(&argc, &argv, NULL);
-
     qtest_add_func("/vmgenid/vmgenid/set-guid",
                    vmgenid_set_guid_test);
     qtest_add_func("/vmgenid/vmgenid/set-guid-auto",