accel/kvm: Use negative KVM type for error propagation

On MIPS, kvm_arch_get_default_type() returns a negative value when an
error occurred so handle the case. Also, let other machines return
negative values when errors occur and declare returning a negative
value as the correct way to propagate an error that happened when
determining KVM type.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Message-id: 20230727073134.134102-5-akihiko.odaki@daynix.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index b472301637..3bac5aa678 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -2527,6 +2527,11 @@ static int kvm_init(MachineState *ms)
         type = kvm_arch_get_default_type(ms);
     }
 
+    if (type < 0) {
+        ret = -EINVAL;
+        goto err;
+    }
+
     do {
         ret = kvm_ioctl(s, KVM_CREATE_VM, type);
     } while (ret == -EINTR);