All, Updated to 4.14.3 breaks virtualbox 5.1.30 OSE (released 11/17) modules rebuild. The pacman error is: ==> dkms install vboxhost/5.1.30 -k 4.14.3-1-ARCH Error! Bad return status for module build on kernel: 4.14.3-1-ARCH (x86_64) Consult /var/lib/dkms/vboxhost/5.1.30/build/make.log for more information. The make.log error is: /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c: In function ‘vboxNetFltLinuxSkBufFromSG’: /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c:726:24: error: ‘SKB_GSO_UDP’ undeclared (first use in this function); did you mean ‘SKB_GSO_ESP’? fGsoType = SKB_GSO_UDP; ^~~~~~~~~~~ SKB_GSO_ESP /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c:726:24: note: each undeclared identifier is reported only once for each function it appears in In file included from /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/include/iprt/types.h:29:0, from /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/r0drv/linux/the-linux-kernel.h:34, from /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c:24: /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c: In function ‘vboxNetFltLinuxCanForwardAsGso’: LD [M] /var/lib/dkms/vboxhost/5.1.30/build/vboxnetadp/vboxnetadp.o /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c:1112:53: error: ‘SKB_GSO_UDP’ undeclared (first use in this function); did you mean ‘SKB_GSO_ESP’? if (RT_UNLIKELY( skb_shinfo(pSkb)->gso_type & ~(SKB_GSO_UDP | SKB_GSO_DODGY | SKB_GSO_TCPV6 | SKB_GSO_TCPV4) )) ^ /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/include/iprt/cdefs.h:1612:53: note: in definition of macro ‘RT_UNLIKELY’ # define RT_UNLIKELY(expr) __builtin_expect(!!(expr), 0) ^~~~ /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c: In function ‘vboxNetFltLinuxForwardToIntNet’: /var/lib/dkms/vboxhost/5.1.30/build/vboxnetflt/linux/VBoxNetFlt-linux.c:1405:47: error: ‘SKB_GSO_UDP’ undeclared (first use in this function); did you mean ‘SKB_GSO_ESP’? if ( (skb_shinfo(pBuf)->gso_type & (SKB_GSO_UDP | SKB_GSO_TCPV6 | SKB_GSO_TCPV4)) ^~~~~~~~~~~ SKB_GSO_ESP This worked fine in the last kernel. Is there a reason this should break now? Virtualbox 5.2 is currently not an option until a few bugs are fixed affecting the headless clients I run (e.g. https://www.virtualbox.org/ticket/17259) Is there a workaround that could define this constant, or was this inadvertently left out of the latest kernel? Let me know if a bug is needed, I'm happy to file it. -- David C. Rankin, J.D.,P.E.