On 17 Jun 2016 6:23 p.m., "Chris Wilson" <<a href="mailto:chris@chris-wilson.co.uk">chris@chris-wilson.co.uk</a>> wrote: > > On Fri, Jun 17, 2016 at 06:12:16PM +0800, Daniel J Blueman wrote: > > On 17 June 2016 at 17:18, Chris Wilson <<a href="mailto:chris@chris-wilson.co.uk">chris@chris-wilson.co.uk</a>> wrote: > > > On Fri, Jun 17, 2016 at 05:08:55PM +0800, Daniel J Blueman wrote: > > >> Hi all! > > >> > > >> When unlocking from lightdm, the mouse cursor isn't visible until > > >> switching VTs. This doesn't occur when using UXA rendering mode > > >> though, and affects a *lot* of people [1]. It occurs with a range of > > >> kernels including 4.6.2. > > >> > > >> I'm using xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1 > > >> (current in Ubuntu 16.04 LTS). > > >> > > >> How can I approach debugging it? > > > > > > Start with a kernel from about 3.19. The trigger was introduced by > > > xorg-server-1.18.3 which double applied a SETCURSOR ioctl. That should > > > have been a noop... > > > > Thanks for replying Chris! > > > > I find the issue occurs in kernels 4.6.2, 4.4.13 and 4.3.6, but does > > not in 4.2.8 or 4.1.26, however I also see that locking the screen > > doesn't blank it, so there is behavioural difference also. > > > > This may result in a kernel bisect tripping on a large merge; I can > > take a look if you think the odds are ok? > > I would look at -nightly first and hope that is has been fixed (and that > the fix is trivial). No cigar with -nightly, so I'll follow up in a few days after I get through the 4.2-4.3 kernel bisection. Daniel