id summary reporter owner description type status component version resolution keywords cc guest host 11664 Please support compiling with CONFIG_USER_NS=y => Fixed in SVN kevinoid "When compiling the VirtualBox kernel module with recent kernels with CONFIG_USER_NS enabled, the compile fails with the following messages: /path-to/vboxdrv/linux/SUPDrv-linux.c: In function ‘vboxdrvLinuxUid’: /path-to/vboxdrv/linux/SUPDrv-linux.c:226:5: error: incompatible types when returning type ‘kuid_t’ but ‘RTUID’ was expected /path-to/vboxdrv/linux/SUPDrv-linux.c: In function ‘vboxdrvLinuxGid’: /path-to/vboxdrv/linux/SUPDrv-linux.c:235:5: error: incompatible types when returning type ‘kgid_t’ but ‘RTGID’ was expected /path-to/vboxdrv/linux/SUPDrv-linux.c: In function ‘vboxdrvLinuxEuid’: /path-to/vboxdrv/linux/SUPDrv-linux.c:244:5: error: incompatible types when returning type ‘kuid_t’ but ‘RTUID’ was expected /path-to/vboxdrv/linux/SUPDrv-linux.c:248:1: warning: control reaches end of non-void function [-Wreturn-type] /path-to/vboxdrv/linux/SUPDrv-linux.c: In function ‘vboxdrvLinuxUid’: /path-to/vboxdrv/linux/SUPDrv-linux.c:230:1: warning: control reaches end of non-void function [-Wreturn-type] /path-to/vboxdrv/linux/SUPDrv-linux.c: In function ‘vboxdrvLinuxGid’: /path-to/vboxdrv/linux/SUPDrv-linux.c:239:1: warning: control reaches end of non-void function [-Wreturn-type] This is due to CONFIG_UIDGID_STRICT_TYPE_CHECKS, which is selected by CONFIG_USER_NS and causes kuid_t and kgid_t to be defined as structs. This was recently noted on the vbox-dev ML . I also came across a patch to address the issue , although I have no knowledge of its suitability and have not tested it. Thanks!" defect closed other VirtualBox 4.2.10 fixed other other