I'm porting some legacy code initially developed in Xen 4.0 and Linux 2.6 to longterm support kernels 3.2.93 and 4.4.88, and Xen 4.6 or 4.8 (not decided yet but that's not the key issue). My legacy work involves dealing with event channel and xen-netfront/netback drivers. However, I found a lot of things in Linux 3.2.93 and 4.4.88 are different from Linux 2.6.32. I would be appreciated if anyone knows about detailed API changes (especially the event channel and pv net driver parts). Currently all googling results I found are about linux 2.6 and Xen 4.0/3.x, I will keep digging the devel mailing list.