Re: Xorg & i915 & backport-kernel causing BUG

["Rebecca N. Palmer" <rebecca_palmer@zoho.com>]

What i915 (Intel GPU) device do you have? ( lspci -nn | grep -e 
"\[03..\]:" )

Are you also using the libdrm/mesa backports? ( dpkg -l libdrm* libgl1* )

As the error is coming from framebuffer compression code (somewhere in 
https://sources.debian.net/src/linux/4.5.4-1~bpo8%2B1/drivers/gpu/drm/i915/intel_fbc.c/#L736 
), turning that feature off might help: add i915.enable_fbc=0 to your 
kernel command line (https://wiki.ubuntu.com/Kernel/KernelBootParameters).