drivers: hv: mshv_vtl: return 0 for MSHV_CAP_LOWER_VTL_TIMER_VIRT if feature unsupported

Returning -EOPNOTSUPP is a fatal error. It means that the driver doesn't know the feature. Not that the feature is not supported due to the runtime platform reason. Return 0 for MSHV_CAP_LOWER_VTL_TIMER_VIRT on non-TDX platform, which is safer.

Fixes: 3528fd7: 3528fd7 ("drivers: hv: mshv_vtl: Advertise TDX timer service extension")

Author: hargar19

drivers/hv/mshv_vtl_main.c

@@ -332,7 +332,7 @@ static long __mshv_vtl_ioctl_check_extension(u32 arg)
 	case MSHV_CAP_LOWER_VTL_TIMER_VIRT:
 		if (hv_isolation_type_tdx())
 			return mshv_tdx_vtl_ioctl_check_extension(arg);
-		break;
+		return 0;
 	}
 
 	return -EOPNOTSUPP;