This one still appears with kernel 4.6.0-040600rc4-generic:

[   18.212146] ------------[ cut here ]------------
[   18.212175] WARNING: CPU: 0 PID: 1052 at /home/kernel/COD/linux/drivers/gpu/drm/i915/intel_pm.c:3572 skl_update_other_pipe_wm+0x16c/0x180 [i915]
[   18.212176] WARN_ON(!wm_changed)
[   18.212176] Modules linked in:
[   18.212177]  bnep uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core videodev media btusb btrtl btbcm btintel bluetooth binfmt_misc nls_iso8859_1 
arc4 snd_hda_codec_hdmi snd_hda_codec_realtek iwlmvm snd_hda_codec_generic snd_soc_skl snd_soc_skl_ipc mac80211 snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core snd_soc_sst
_match snd_soc_core iwlwifi snd_compress ac97_bus snd_pcm_dmaengine intel_rapl cfg80211 x86_pkg_temp_thermal dw_dmac_core joydev input_leds intel_powerclamp coretemp snd_hd
a_intel snd_hda_codec rtsx_pci_ms snd_hda_core snd_hwdep memstick snd_pcm serio_raw thinkpad_acpi nvram shpchp intel_pch_thermal snd_seq_midi mei_me snd_seq_midi_event mei 
snd_rawmidi snd_seq snd_seq_device snd_timer snd soundcore tpm_crb mac_hid kvm_intel kvm irqbypass parport_pc ppdev lp parport
[   18.212212]  autofs4 algif_skcipher af_alg dm_crypt hid_microsoft hid_generic usbhid hid rtsx_pci_sdmmc crct10dif_pclmul crc32_pclmul ghash_clmulni_intel i915 aesni_inte
l aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd i2c_algo_bi
t drm_kms_helper syscopyarea psmouse e1000e sysfillrect sysimgblt fb_sys_fops ptp pps_core drm nvme nvme_core rtsx_pci wmi video fjes
[   18.212225] CPU: 0 PID: 1052 Comm: Xorg Tainted: G        W       4.6.0-040600rc4-generic #201604172330
[   18.212225] Hardware name: LENOVO 20F9CTO1WW/20F9CTO1WW, BIOS N1CET40W (1.08 ) 03/09/2016
[   18.212226]  0000000000000286 000000009840ec1d ffff8800d2a77988 ffffffff813eee03
[   18.212228]  ffff8800d2a779d8 0000000000000000 ffff8800d2a779c8 ffffffff810827cb
[   18.212229]  00000df400200004 ffff880502351000 ffff880501e39da4 ffff880502352000
[   18.212231] Call Trace:
[   18.212235]  [<ffffffff813eee03>] dump_stack+0x63/0x90
[   18.212237]  [<ffffffff810827cb>] __warn+0xcb/0xf0
[   18.212239]  [<ffffffff8108284f>] warn_slowpath_fmt+0x5f/0x80
[   18.212248]  [<ffffffffc02ad5ec>] skl_update_other_pipe_wm+0x16c/0x180 [i915]
[   18.212256]  [<ffffffffc02ad785>] skl_update_wm+0x185/0x640 [i915]
[   18.212264]  [<ffffffffc02b154e>] intel_update_watermarks+0x1e/0x30 [i915]
[   18.212277]  [<ffffffffc0319f09>] intel_atomic_commit+0x469/0xdc0 [i915]
[   18.212289]  [<ffffffffc007fc31>] ? drm_atomic_check_only+0x181/0x600 [drm]
[   18.212296]  [<ffffffffc00800e7>] drm_atomic_commit+0x37/0x60 [drm]
[   18.212301]  [<ffffffffc0185f2a>] drm_atomic_helper_set_config+0x7a/0xb0 [drm_kms_helper]
[   18.212309]  [<ffffffffc007ed6a>] ? drm_modeset_lock_all_ctx+0x9a/0xb0 [drm]
[   18.212316]  [<ffffffffc006fb42>] drm_mode_set_config_internal+0x62/0x100 [drm]
[   18.212324]  [<ffffffffc0073a90>] drm_mode_setcrtc+0x3e0/0x500 [drm]
[   18.212326]  [<ffffffff8171507b>] ? sock_recvmsg+0x3b/0x50
[   18.212331]  [<ffffffffc0064ab2>] drm_ioctl+0x152/0x540 [drm]
[   18.212337]  [<ffffffffc00736b0>] ? drm_mode_setplane+0x1b0/0x1b0 [drm]
[   18.212340]  [<ffffffff810f3722>] ? hrtimer_start_range_ns+0x1d2/0x3d0
[   18.212341]  [<ffffffff812336c1>] do_vfs_ioctl+0xa1/0x5b0
[   18.212343]  [<ffffffff81090731>] ? __set_task_blocked+0x41/0xa0
[   18.212344]  [<ffffffff81716b80>] ? __sys_recvmsg+0x80/0x90
[   18.212346]  [<ffffffff810930b6>] ? __set_current_blocked+0x36/0x60
[   18.212347]  [<ffffffff81233c49>] SyS_ioctl+0x79/0x90
[   18.212349]  [<ffffffff81093364>] ? SyS_rt_sigprocmask+0x74/0xc0
[   18.212350]  [<ffffffff8183f936>] entry_SYSCALL_64_fastpath+0x1e/0xa8
[   18.212351] ---[ end trace bf7887729b3adb93 ]---