the situation is the same after an upgrade to 18.10. the graphics freezes for about 25 seconds each time one switches from tty to graphical console or when lightdm/gdm starts. i am attaching the dmesg output where several such freezes can be seen. it's all related to a timeout in blanking the screen.
** Attachment added: "dmesg output containing several drm freezes, see "timeout"" https://bugs.launchpad.net/ubuntu/+source/libdrm/+bug/1789258/+attachment/5203280/+files/dmesg.txt -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to libdrm in Ubuntu. https://bugs.launchpad.net/bugs/1789258 Title: drm:drm_atomic_helper_wait_for_dependencies flip_done timed out To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/libdrm/+bug/1789258/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp