This test would have identified the crash caused by the addition of new
balloon stats fields.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
---
 tests/qtest/virtio-balloon-test.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/tests/qtest/virtio-balloon-test.c b/tests/qtest/virtio-balloon-test.c
index 6bea33b590..ecdd363b06 100644
--- a/tests/qtest/virtio-balloon-test.c
+++ b/tests/qtest/virtio-balloon-test.c
@@ -8,6 +8,7 @@
 
 #include "qemu/osdep.h"
 #include "libqtest.h"
+#include "standard-headers/linux/virtio_balloon.h"
 
 /*
  * https://gitlab.com/qemu-project/qemu/-/issues/2576
@@ -26,11 +27,30 @@ static void oss_fuzz_71649(void)
     qtest_quit(s);
 }
 
+static void query_stats(void)
+{
+    QTestState *s = qtest_init("-device virtio-balloon,id=balloon"
+                               " -nodefaults");
+    QDict *ret = qtest_qmp_assert_success_ref(
+        s,
+        "{ 'execute': 'qom-get', 'arguments': "     \
+        "{ 'path': '/machine/peripheral/balloon', " \
+        "  'property': 'guest-stats' } }");
+    QDict *stats = qdict_get_qdict(ret, "stats");
+
+    /* We expect 1 entry in the dict for each known kernel stat */
+    assert(qdict_size(stats) == VIRTIO_BALLOON_S_NR);
+
+    qobject_unref(ret);
+    qtest_quit(s);
+}
+
 int main(int argc, char **argv)
 {
     g_test_init(&argc, &argv, NULL);
 
     qtest_add_func("virtio-balloon/oss_fuzz_71649", oss_fuzz_71649);
+    qtest_add_func("virtio-balloon/query-stats", query_stats);
 
     return g_test_run();
 }
-- 
2.46.0

Daniel P. Berrangé <berrange@redhat.com> writes:

> This test would have identified the crash caused by the addition of new
> balloon stats fields.
>
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> ---
>  tests/qtest/virtio-balloon-test.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>
> diff --git a/tests/qtest/virtio-balloon-test.c b/tests/qtest/virtio-balloon-test.c
> index 6bea33b590..ecdd363b06 100644
> --- a/tests/qtest/virtio-balloon-test.c
> +++ b/tests/qtest/virtio-balloon-test.c
> @@ -8,6 +8,7 @@
>  
>  #include "qemu/osdep.h"
>  #include "libqtest.h"
> +#include "standard-headers/linux/virtio_balloon.h"
>  
>  /*
>   * https://gitlab.com/qemu-project/qemu/-/issues/2576
> @@ -26,11 +27,30 @@ static void oss_fuzz_71649(void)
>      qtest_quit(s);
>  }
>  
> +static void query_stats(void)
> +{
> +    QTestState *s = qtest_init("-device virtio-balloon,id=balloon"
> +                               " -nodefaults");
> +    QDict *ret = qtest_qmp_assert_success_ref(
> +        s,
> +        "{ 'execute': 'qom-get', 'arguments': "     \
> +        "{ 'path': '/machine/peripheral/balloon', " \
> +        "  'property': 'guest-stats' } }");
> +    QDict *stats = qdict_get_qdict(ret, "stats");
> +
> +    /* We expect 1 entry in the dict for each known kernel stat */
> +    assert(qdict_size(stats) == VIRTIO_BALLOON_S_NR);
> +
> +    qobject_unref(ret);
> +    qtest_quit(s);
> +}
> +
>  int main(int argc, char **argv)
>  {
>      g_test_init(&argc, &argv, NULL);
>  
>      qtest_add_func("virtio-balloon/oss_fuzz_71649", oss_fuzz_71649);
> +    qtest_add_func("virtio-balloon/query-stats", query_stats);
>  
>      return g_test_run();
>  }

Reviewed-by: Fabiano Rosas <farosas@suse.de>