Unfortunately, I can see this warning with the 4.2.0-16 kernel, as well:

Oct 30 07:56:24 fozzy kernel: [ 1314.912537] WARNING: CPU: 0 PID: 0 at /build/linux-AxjFAn/linux-4.2.0/drivers/gpu/drm/i915/intel_display.c:11100 intel_check_page_flip+0xfc/0x110 [i915]()
Oct 30 07:56:24 fozzy kernel: [ 1314.912538] Kicking stuck page flip: queued at 78664, now 78668
Oct 30 07:56:24 fozzy kernel: [ 1314.912539] Modules linked in: binfmt_misc dm_crypt drbg ansi_cprng algif_skcipher af_alg uvcvideo 
videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common snd_usb_audio videodev snd_usbmidi_lib hid_multitouch media snd_hda_co
dec_hdmi nls_iso8859_1 snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel eeepc_wmi snd_hda_codec asus_wmi sparse_keymap snd_
hda_core snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event intel_rapl iosf_mbi x86_pkg_temp_thermal intel_powerclamp coretemp kvm_in
tel snd_rawmidi kvm crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 snd_seq lrw gf128mul glue_helper ablk_h
elper cryptd snd_seq_device snd_timer serio_raw joydev snd soundcore mei_me shpchp mei 8250_fintek acpi_als kfifo_buf industrialio m
ac_hid acpi_pad ip6t_REJECT nf_reject_ipv6 intel_lpss_acpi intel_lpss nf_log_ipv6 xt_hl ip6t_rt nf_conntrack_ipv6 nf_defrag_ipv6 ipt
_REJECT nf_reject_ipv4 nf_log_ipv4 nf_log_common xt_LOG xt_limit xt_tcpudp xt_addrtype nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack
 ip6table_filter ip6_tables nf_conntrack_netbios_ns nf_conntrack_broadcast nf_nat_ftp nf_nat nf_conntrack_ftp nf_conntrack iptable_f
ilter ip_tables x_tables parport_pc ppdev lp parport autofs4 btrfs xor raid6_pq hid_generic usbhid mxm_wmi i915 psmouse e1000e i2c_a
lgo_bit drm_kms_helper ptp pps_core drm ahci libahci wmi video pinctrl_sunrisepoint pinctrl_intel i2c_hid hid
Oct 30 07:56:24 fozzy kernel: [ 1314.912594] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.2.0-16-generic #19-Ubuntu
Oct 30 07:56:24 fozzy kernel: [ 1314.912595] Hardware name: System manufacturer System Product Name/Z170-A, BIOS 1101 10/01/2015
Oct 30 07:56:24 fozzy kernel: [ 1314.912596]  0000000000000000 cc4f269da8d07096 ffff880473c03d48 ffffffff817e8c09
Oct 30 07:56:24 fozzy kernel: [ 1314.912598]  0000000000000000 ffff880473c03da0 ffff880473c03d88 ffffffff8107b3c6
Oct 30 07:56:24 fozzy kernel: [ 1314.912599]  ffff880473c03db8 ffff88045b2e6000 ffff880460046000 ffff88045b2e61a8
Oct 30 07:56:24 fozzy kernel: [ 1314.912601] Call Trace:
Oct 30 07:56:24 fozzy kernel: [ 1314.912602]  <IRQ>  [<ffffffff817e8c09>] dump_stack+0x45/0x57
Oct 30 07:56:24 fozzy kernel: [ 1314.912607]  [<ffffffff8107b3c6>] warn_slowpath_common+0x86/0xc0
Oct 30 07:56:24 fozzy kernel: [ 1314.912609]  [<ffffffff8107b455>] warn_slowpath_fmt+0x55/0x70
Oct 30 07:56:24 fozzy kernel: [ 1314.912620]  [<ffffffffc0223b3c>] intel_check_page_flip+0xfc/0x110 [i915]
Oct 30 07:56:24 fozzy kernel: [ 1314.912629]  [<ffffffffc01ec5e5>] gen8_irq_handler+0x325/0x590 [i915]
Oct 30 07:56:24 fozzy kernel: [ 1314.912632]  [<ffffffff810d41d4>] handle_irq_event_percpu+0x74/0x180
Oct 30 07:56:24 fozzy kernel: [ 1314.912633]  [<ffffffff810d4329>] handle_irq_event+0x49/0x70
Oct 30 07:56:24 fozzy kernel: [ 1314.912634]  [<ffffffff810d76a1>] handle_edge_irq+0x81/0x150
Oct 30 07:56:24 fozzy kernel: [ 1314.912636]  [<ffffffff81017295>] handle_irq+0x25/0x40
Oct 30 07:56:24 fozzy kernel: [ 1314.912638]  [<ffffffff817f25ef>] do_IRQ+0x4f/0xe0
Oct 30 07:56:24 fozzy kernel: [ 1314.912639]  [<ffffffff817f056b>] common_interrupt+0x6b/0x6b
Oct 30 07:56:24 fozzy kernel: [ 1314.912640]  <EOI>  [<ffffffff810e77a4>] ? enqueue_hrtimer+0x44/0x80
Oct 30 07:56:24 fozzy kernel: [ 1314.912644]  [<ffffffff81686930>] ? cpuidle_enter_state+0x130/0x270
Oct 30 07:56:24 fozzy kernel: [ 1314.912645]  [<ffffffff8168690b>] ? cpuidle_enter_state+0x10b/0x270
Oct 30 07:56:24 fozzy kernel: [ 1314.912646]  [<ffffffff81686aa7>] cpuidle_enter+0x17/0x20
Oct 30 07:56:24 fozzy kernel: [ 1314.912648]  [<ffffffff810bd432>] call_cpuidle+0x32/0x60
Oct 30 07:56:24 fozzy kernel: [ 1314.912649]  [<ffffffff81686a83>] ? cpuidle_select+0x13/0x20
Oct 30 07:56:24 fozzy kernel: [ 1314.912650]  [<ffffffff810bd6c8>] cpu_startup_entry+0x268/0x320
Oct 30 07:56:24 fozzy kernel: [ 1314.912652]  [<ffffffff817dd16c>] rest_init+0x7c/0x80
Oct 30 07:56:24 fozzy kernel: [ 1314.912654]  [<ffffffff81d50025>] start_kernel+0x48b/0x4ac
Oct 30 07:56:24 fozzy kernel: [ 1314.912656]  [<ffffffff81d4f120>] ? early_idt_handler_array+0x120/0x120
Oct 30 07:56:24 fozzy kernel: [ 1314.912657]  [<ffffffff81d4f339>] x86_64_start_reservations+0x2a/0x2c
Oct 30 07:56:24 fozzy kernel: [ 1314.912658]  [<ffffffff81d4f485>] x86_64_start_kernel+0x14a/0x16d

I also saw an error:

Oct 31 02:16:44 fozzy kernel: [22225.384478] [drm:intel_pipe_update_end [i915]] *ERROR* Atomic update failure on pipe A (start=0 end=1)