The issue looks fixed in Intel DRM nightly kernel, see on FDO for details: https://bugs.freedesktop.org/show_bug.cgi?id=90342#c7
The bug is still present in Debian unstable kernel 4.1.3-1 though. I'll try to narrow down when the fix landed as time allows. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org