diff -ur kernel-source-virtualbox-5.2.34/kernel-source-vboxdrv-5.2.34/r0drv/linux/thread2-r0drv-linux.c kernel-source-virtualbox-5.2.34.fixed/kernel-source-vboxdrv-5.2.34/r0drv/linux/thread2-r0drv-linux.c
--- kernel-source-vboxdrv-5.2.34/r0drv/linux/thread2-r0drv-linux.c	2019-10-21 11:53:32.000000000 +0000
+++ kernel-source-vboxdrv-5.2.34.new/r0drv/linux/thread2-r0drv-linux.c	2019-12-12 01:12:12.601586194 +0000
@@ -36,6 +36,9 @@
 #include <iprt/err.h>
 #include "internal/thread.h"
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 11, 0)
+    #include <uapi/linux/sched/types.h>
+#endif /* >= KERNEL_VERSION(4, 11, 0) */
 
 RTDECL(RTTHREAD) RTThreadSelf(void)
 {