I believe I am experiencing this issue also. Dell Optiplex 7040 with Intel I7-6700 (skylake) with integrated graphics (Intel HD 530) running Ubuntu 14.04.3 LTS.
Two monitors are connected via displayport cables. Issue also occurred when using displayport to DVI adapters. The following is logged to /var/log/syslog every time I move the mouse cursor between screens. Occasionally when I move the mouse cursor to the other screen, the screen will blank and then a few seconds later come back on. Windows are not re-arranged (implying it is not the disappearance of a screen), and similar log entries are produced. No other rendering issues or graphics issues have been noted - Unity works fine. Running tuxracer does not cause any issues. If there is any additional information I can provide that would be helpful please let me know. Feb 9 10:07:56 computer-name kernel: [595457.353689] ------------[ cut here ]------------ Feb 9 10:07:56 computer-name kernel: [595457.353710] WARNING: CPU: 4 PID: 1929 at /build/linux-lts-vivid-LIqOuh/linux-lts-vivid-3.19.0/ubuntu/i915/intel_pm.c:3406 skl_update_other_pipe_wm+0x210/0x220 [i915_bpo]() Feb 9 10:07:56 computer-name kernel: [595457.353711] WARN_ON(!wm_changed) Feb 9 10:07:56 computer-name kernel: [595457.353712] Modules linked in: snd_seq_dummy cuse uas usb_storage vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) xt_conntrack ipt_MASQUERADE nf_nat_masquerade_ipv4 iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 xt_addrtype iptable_filter ip_tables x_tables nf_nat nf_conntrack br_netfilter bridge stp llc aufs pci_stub rfcomm bnep bluetooth binfmt_misc twofish_generic twofish_avx_x86_64 twofish_x86_64_3way twofish_x86_64 twofish_common xts snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi joydev snd_seq snd_seq_device x86_pkg_temp_thermal coretemp snd_timer dell_wmi sparse_keymap kvm_intel dcdbas kvm snd serio_raw soundcore 8250_fintek i2c_hid mac_hid acpi_pad i915_bpo intel_ips drm_kms_helper drm i2c_algo_bit shpchp parport_pc ppdev lp parport nls_iso8859_1 dm_crypt hid_generic usbhid hid crct10dif_pclmul c rc32_pclmul aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd e1000e psmouse ptp ahci pps_core nvme libahci wmi video [last unloaded: vboxdrv] Feb 9 10:07:56 computer-name kernel: [595457.353749] CPU: 4 PID: 1929 Comm: Xorg Tainted: G W OE 3.19.0-49-generic #55~14.04.1-Ubuntu Feb 9 10:07:56 computer-name kernel: [595457.353750] Hardware name: Dell Inc. OptiPlex 7040/0Y7WYT, BIOS 1.0.1 09/01/2015 Feb 9 10:07:56 computer-name kernel: [595457.353751] ffffffffc05f4268 ffff88045cbb7598 ffffffff817b01b5 0000000000000000 Feb 9 10:07:56 computer-name kernel: [595457.353753] ffff88045cbb75e8 ffff88045cbb75d8 ffffffff81074dea ffff88045cbb7710 Feb 9 10:07:56 computer-name kernel: [595457.353755] ffff88045f18b000 ffff88045cbb7680 ffff88045cbb7734 ffff88045f18d000 Feb 9 10:07:56 computer-name kernel: [595457.353757] Call Trace: Feb 9 10:07:56 computer-name kernel: [595457.353762] [<ffffffff817b01b5>] dump_stack+0x45/0x57 Feb 9 10:07:56 computer-name kernel: [595457.353765] [<ffffffff81074dea>] warn_slowpath_common+0x8a/0xc0 Feb 9 10:07:56 computer-name kernel: [595457.353767] [<ffffffff81074e66>] warn_slowpath_fmt+0x46/0x50 Feb 9 10:07:56 computer-name kernel: [595457.353775] [<ffffffffc0533700>] skl_update_other_pipe_wm+0x210/0x220 [i915_bpo] Feb 9 10:07:56 computer-name kernel: [595457.353784] [<ffffffffc0533915>] skl_update_wm+0x205/0x850 [i915_bpo] Feb 9 10:07:56 computer-name kernel: [595457.353797] [<ffffffffc057db0e>] ? gen9_read32+0x6e/0x2f0 [i915_bpo] Feb 9 10:07:56 computer-name kernel: [595457.353806] [<ffffffffc05349fe>] intel_update_watermarks+0x1e/0x30 [i915_bpo] Feb 9 10:07:56 computer-name kernel: [595457.353820] [<ffffffffc059aad0>] intel_finish_crtc_commit+0x190/0x1b0 [i915_bpo] Feb 9 10:07:56 computer-name kernel: [595457.353827] [<ffffffffc05076c9>] drm_atomic_helper_commit_planes_on_crtc+0x169/0x240 [drm_kms_helper] Feb 9 10:07:56 computer-name kernel: [595457.353842] [<ffffffffc05b4af8>] intel_atomic_commit+0x68/0x100 [i915_bpo] Feb 9 10:07:56 computer-name kernel: [595457.353853] [<ffffffffc04a81f7>] drm_atomic_commit+0x37/0x60 [drm] Feb 9 10:07:56 computer-name kernel: [595457.353859] [<ffffffffc0505e75>] drm_atomic_helper_disable_plane+0xf5/0x140 [drm_kms_helper] Feb 9 10:07:56 computer-name kernel: [595457.353862] [<ffffffff810bb7e9>] ? mutex_optimistic_spin+0x139/0x1f0 Feb 9 10:07:56 computer-name kernel: [595457.353870] [<ffffffffc0497cc0>] __setplane_internal+0x1d0/0x2c0 [drm] Feb 9 10:07:56 computer-name kernel: [595457.353873] [<ffffffff817b5636>] ? __ww_mutex_lock_slowpath+0x152/0x16c Feb 9 10:07:56 computer-name kernel: [595457.353880] [<ffffffffc0497ecc>] drm_mode_cursor_universal+0x11c/0x200 [drm] Feb 9 10:07:56 computer-name kernel: [595457.353882] [<ffffffff817b56af>] ? __ww_mutex_lock+0x5f/0x97 Feb 9 10:07:56 computer-name kernel: [595457.353889] [<ffffffffc049802c>] drm_mode_cursor_common+0x7c/0x1b0 [drm] Feb 9 10:07:56 computer-name kernel: [595457.353892] [<ffffffff81080757>] ? __sigqueue_free.part.12+0x37/0x40 Feb 9 10:07:56 computer-name kernel: [595457.353900] [<ffffffffc049c301>] drm_mode_cursor_ioctl+0x41/0x50 [drm] Feb 9 10:07:56 computer-name kernel: [595457.353906] [<ffffffffc048caac>] drm_ioctl+0x1ec/0x660 [drm] Feb 9 10:07:56 computer-name kernel: [595457.353910] [<ffffffff811ffda8>] do_vfs_ioctl+0x2f8/0x510 Feb 9 10:07:56 computer-name kernel: [595457.353912] [<ffffffff810818f2>] ? __set_task_blocked+0x32/0x70 Feb 9 10:07:56 computer-name kernel: [595457.353914] [<ffffffff811ecfd8>] ? __vfs_read+0x18/0x50 Feb 9 10:07:56 computer-name kernel: [595457.353917] [<ffffffff81084356>] ? __set_current_blocked+0x36/0x90 Feb 9 10:07:56 computer-name kernel: [595457.353918] [<ffffffff81200041>] SyS_ioctl+0x81/0xa0 Feb 9 10:07:56 computer-name kernel: [595457.353921] [<ffffffff817b7c0d>] system_call_fastpath+0x16/0x1b Feb 9 10:07:56 computer-name kernel: [595457.353922] ---[ end trace ca051f728083824b ]--- -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1523088 Title: WARN_ON(!wm_changed) warning and stacktrace in kernel log Status in X.Org X server: Confirmed Status in linux package in Ubuntu: Incomplete Bug description: I always get an warning and stacktrace (and it seems to hang a little bit). This occurs after reboot as well as when I move with the cursor between my hdmi monitor and my laptop. (This only occurs when HDMI is connected) Default Kubuntu install version 15.10 with kernel 4.2.0-19-generic Processor: i5 6300hq Graphics: gtx950m WARNING: CPU: 1 PID: 827 at /build/linux-26_gwp/linux-4.2.0/drivers/gpu/drm/i915/intel_pm.c:3404 skl_update_other_pipe_wm+0x1de/0x1f0 [i915]() [Sam Dez 5 12:34:46 2015] WARN_ON(!wm_changed) [Sam Dez 5 12:34:46 2015] Modules linked in: [Sam Dez 5 12:34:46 2015] nls_iso8859_1 pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) drbg ansi_cprng ctr ccm rfcomm bnep arc4 rtsx_usb_ms memstick i2c_designware_platform i2c_designware_core acer_wmi sparse_keymap snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core intel_rapl snd_hwdep iosf_mbi x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq crct10dif_pclmul crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul snd_seq_device glue_helper snd_timer ablk_helper cryptd ath10k_pci ath10k_core snd ath mac80211 serio_raw soundcore idma64 virt_dma cfg80211 joydev input_leds uvcvideo mei_me videobuf2_vmalloc videobuf2_memops mei videobuf2_core v4l2_common intel_lpss_pci videodev media [Sam Dez 5 12:34:46 2015] btusb btrtl btbcm btintel bluetooth shpchp dell_smo8800 intel_lpss_acpi intel_lpss tpm_crb acpi_pad mac_hid parport_pc ppdev lp parport autofs4 hid_generic hid_logitech_hidpp hid_logitech_dj usbhid rtsx_usb_sdmmc rtsx_usb uas usb_storage nouveau i915 mxm_wmi ttm i2c_algo_bit drm_kms_helper r8169 mii drm ahci libahci i2c_hid hid wmi pinctrl_sunrisepoint video pinctrl_intel [Sam Dez 5 12:34:46 2015] CPU: 1 PID: 827 Comm: Xorg Tainted: G W OE 4.2.0-19-generic #23-Ubuntu [Sam Dez 5 12:34:46 2015] Hardware name: Acer Aspire V5-591G/Usopp_SLS, BIOS V1.03 10/23/2015 [Sam Dez 5 12:34:46 2015] 0000000000000000 00000000a287b8f0 ffff880071b03518 ffffffff817e93f9 [Sam Dez 5 12:34:46 2015] 0000000000000000 ffff880071b03570 ffff880071b03558 ffffffff8107b3d6 [Sam Dez 5 12:34:46 2015] ffff880071b03620 ffff880071b036c4 ffff880279bf2000 ffff880279bf7000 [Sam Dez 5 12:34:46 2015] Call Trace: [Sam Dez 5 12:34:46 2015] [<ffffffff817e93f9>] dump_stack+0x45/0x57 [Sam Dez 5 12:34:46 2015] [<ffffffff8107b3d6>] warn_slowpath_common+0x86/0xc0 [Sam Dez 5 12:34:46 2015] [<ffffffff8107b465>] warn_slowpath_fmt+0x55/0x70 [Sam Dez 5 12:34:46 2015] [<ffffffffc017eb9e>] skl_update_other_pipe_wm+0x1de/0x1f0 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc017ed6b>] skl_update_wm+0x1bb/0x740 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc01ca837>] ? gen9_read32+0xf7/0x2d0 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc01b32a2>] ? i915_get_vblank_timestamp+0x62/0xa0 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc01824be>] intel_update_watermarks+0x1e/0x30 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc01e5ad9>] intel_finish_crtc_commit+0x169/0x190 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc00f3793>] drm_atomic_helper_commit_planes_on_crtc+0x143/0x260 [drm_kms_helper] [Sam Dez 5 12:34:46 2015] [<ffffffffc01fee3b>] intel_atomic_commit+0x6b/0x100 [i915] [Sam Dez 5 12:34:46 2015] [<ffffffffc0094d47>] drm_atomic_commit+0x37/0x60 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffffc00f20cf>] drm_atomic_helper_disable_plane+0xef/0x130 [drm_kms_helper] [Sam Dez 5 12:34:46 2015] [<ffffffffc008493a>] __setplane_internal+0x23a/0x2f0 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffffc0084b1b>] drm_mode_cursor_universal+0x12b/0x210 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffff817edf2f>] ? __ww_mutex_lock+0x5f/0xa0 [Sam Dez 5 12:34:46 2015] [<ffffffffc0084c81>] drm_mode_cursor_common+0x81/0x180 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffffc0088ca0>] drm_mode_cursor_ioctl+0x50/0x70 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffffc0079495>] drm_ioctl+0x125/0x610 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffffc0088c50>] ? drm_mode_setcrtc+0x500/0x500 [drm] [Sam Dez 5 12:34:46 2015] [<ffffffff81210a25>] do_vfs_ioctl+0x295/0x480 [Sam Dez 5 12:34:46 2015] [<ffffffff81087f71>] ? __set_task_blocked+0x41/0xa0 [Sam Dez 5 12:34:46 2015] [<ffffffff81210c89>] SyS_ioctl+0x79/0x90 [Sam Dez 5 12:34:46 2015] [<ffffffff817f01f2>] entry_SYSCALL_64_fastpath+0x16/0x75 [Sam Dez 5 12:34:46 2015] ---[ end trace c72c2dc92b88cd01 ]--- ProblemType: Bug DistroRelease: Ubuntu 15.10 Package: xserver-xorg-core 2:1.17.2-1ubuntu9.1 ProcVersionSignature: Ubuntu 4.2.0-19.23-generic 4.2.6 Uname: Linux 4.2.0-19-generic x86_64 ApportVersion: 2.19.1-0ubuntu5 Architecture: amd64 Date: Sat Dec 5 12:35:24 2015 ExecutablePath: /usr/bin/Xorg InstallationDate: Installed on 2015-12-04 (0 days ago) InstallationMedia: Kubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021) SourcePackage: xorg-server UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/xorg-server/+bug/1523088/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp