Happens to me also. After an Ubuntu Update yesterday (2015/02/05), my wifi stopped working and this message started appearing in DMESG:
[ 3191.808441] ahci 0000:00:1f.2: port does not support device sleep [ 3470.201625] [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in ips_enabled (expected 1, found 0) [ 3470.201635] ------------[ cut here ]------------ [ 3470.201684] WARNING: CPU: 0 PID: 779 at /build/linux-NgsOGa/linux-4.2.0/drivers/gpu/drm/i915/intel_display.c:12328 check_crtc_state+0x2c5/0x440 [i915]() [ 3470.201688] pipe state doesn't match! [ 3470.201690] Modules linked in: nls_utf8 isofs drbg ansi_cprng ctr ccm rtl8192cu rtl_usb rtl8192c_common rtlwifi uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common hid_multitouch hid_generic videodev media usbhid nvram msr arc4 nls_iso8859_1 asus_nb_wmi asus_wmi sparse_keymap wl(POE) intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm iwlmvm crct10dif_pclmul mac80211 crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul iwlwifi glue_helper snd_hda_codec_hdmi ablk_helper cryptd input_leds joydev cfg80211 snd_hda_codec_realtek serio_raw snd_hda_codec_generic lpc_ich shpchp mei_me mei snd_hda_intel snd_hda_codec snd_soc_rt5640 snd_hda_core snd_soc_rl6231 snd_hwdep snd_soc_core snd_compress ac97_bus snd_pcm_dmaengine snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi [ 3470.201782] snd_seq snd_seq_device snd_timer snd soundcore int3402_thermal dw_dmac 8250_dw dw_dmac_core i2c_designware_platform processor_thermal_device snd_soc_sst_acpi i2c_designware_core int340x_thermal_zone int3400_thermal spi_pxa2xx_platform acpi_thermal_rel intel_soc_dts_iosf intel_smartconnect mac_hid parport_pc ppdev lp parport autofs4 uas usb_storage psmouse i915 i2c_algo_bit drm_kms_helper drm ahci libahci wmi sdhci_acpi video sdhci i2c_hid hid [ 3470.201835] CPU: 0 PID: 779 Comm: Xorg Tainted: P W OE 4.2.0-27-generic #32-Ubuntu [ 3470.201839] Hardware name: ASUSTeK COMPUTER INC. UX301LAA/UX301LAA, BIOS UX301LAA.211 06/05/2015 [ 3470.201842] 0000000000000000 0000000076e06d8c ffff8800d924f7c8 ffffffff817eae99 [ 3470.201849] 0000000000000000 ffff8800d924f820 ffff8800d924f808 ffffffff8107b9c6 [ 3470.201854] ffff8800d924f848 ffff8800d924f8b0 ffff8802110a9800 0000000000000001 [ 3470.201861] Call Trace: [ 3470.201873] [<ffffffff817eae99>] dump_stack+0x45/0x57 [ 3470.201883] [<ffffffff8107b9c6>] warn_slowpath_common+0x86/0xc0 [ 3470.201889] [<ffffffff8107ba55>] warn_slowpath_fmt+0x55/0x70 [ 3470.201936] [<ffffffffc01909e1>] ? intel_pipe_config_compare+0xb31/0xc60 [i915] [ 3470.201972] [<ffffffffc0190dd5>] check_crtc_state+0x2c5/0x440 [i915] [ 3470.202014] [<ffffffffc01a4bfd>] intel_modeset_check_state+0x21d/0x6d0 [i915] [ 3470.202052] [<ffffffffc01a5db7>] intel_crtc_set_config+0x4c7/0x580 [i915] [ 3470.202088] [<ffffffffc0096ef5>] ? drm_mode_create+0x25/0x60 [drm] [ 3470.202115] [<ffffffffc00904a6>] drm_mode_set_config_internal+0x66/0x100 [drm] [ 3470.202142] [<ffffffffc0094b39>] drm_mode_setcrtc+0x3e9/0x500 [drm] [ 3470.202160] [<ffffffffc0085495>] drm_ioctl+0x125/0x610 [drm] [ 3470.202167] [<ffffffff811bf301>] ? page_add_file_rmap+0x51/0x60 [ 3470.202191] [<ffffffffc0094750>] ? drm_mode_setplane+0x1b0/0x1b0 [drm] [ 3470.202200] [<ffffffff812110b5>] do_vfs_ioctl+0x295/0x480 [ 3470.202208] [<ffffffff810885e1>] ? __set_task_blocked+0x41/0xa0 [ 3470.202214] [<ffffffff81211319>] SyS_ioctl+0x79/0x90 [ 3470.202220] [<ffffffff817f1c72>] entry_SYSCALL_64_fastpath+0x16/0x75 [ 3470.202224] ---[ end trace 468b83e008c9f4b0 ]--- [ 3552.414664] ahci 0000:00:1f.2: port does not support device sleep Computer: Asus UX301LA, Ubuntu 15.10 fully updated. I am now using a wifi-dongle because the onboard wifi doesn't work anymore :) (not even with a livecd) -- 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/1492764 Title: [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in ips_enabled (expected 1, found 0) Status in Linux: Fix Released Status in linux package in Ubuntu: Incomplete Bug description: System: Kubuntu 15.10 Since kernel version 4.2 I have a few of this errors: Sep 06 16:16:35 benediktZ50-70 kernel: [drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in ips_enabled (expected 1, found 0) Sep 06 16:16:35 benediktZ50-70 kernel: ------------[ cut here ]------------ Sep 06 16:16:35 benediktZ50-70 kernel: WARNING: CPU: 0 PID: 187 at /build/linux-4dBub_/linux-4.2.0/drivers/gpu/drm/i915/intel_display.c:12324 check_crtc_state+0x2c5/0x440 [i915]() Sep 06 16:16:35 benediktZ50-70 kernel: pipe state doesn't match! Sep 06 16:16:35 benediktZ50-70 kernel: Modules linked in: rtsx_usb_sdmmc rtsx_usb i915 i2c_algo_bit drm_kms_helper psmouse ahci drm libahci r8169 mii sdhci_acpi video sdhci i2c_hid hid Sep 06 16:16:35 benediktZ50-70 kernel: CPU: 0 PID: 187 Comm: plymouthd Tainted: G W 4.2.0-7-generic #7-Ubuntu Sep 06 16:16:35 benediktZ50-70 kernel: Hardware name: LENOVO 20354/Lancer 5A5, BIOS 9BCN91WW 07/21/2015 Sep 06 16:16:35 benediktZ50-70 kernel: ffffffffc023f1e8 ffff8802413277e8 ffffffff817b0465 0000000000000000 Sep 06 16:16:35 benediktZ50-70 kernel: ffff880241327838 ffff880241327828 ffffffff81076536 ffff880241327858 Sep 06 16:16:35 benediktZ50-70 kernel: ffff8802413278c0 ffff880241152000 0000000000000001 ffff880241152350 Sep 06 16:16:35 benediktZ50-70 kernel: Call Trace: Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff817b0465>] dump_stack+0x45/0x57 Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff81076536>] warn_slowpath_common+0x86/0xc0 Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff810765b6>] warn_slowpath_fmt+0x46/0x50 Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc01d3091>] ? intel_pipe_config_compare+0xb31/0xc60 [i915] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc01d3485>] check_crtc_state+0x2c5/0x440 [i915] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc01e6f3e>] intel_modeset_check_state+0x20e/0x6b0 [i915] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc01e80e7>] intel_crtc_set_config+0x4c7/0x580 [i915] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc009f915>] ? drm_mode_create+0x25/0x60 [drm] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc0099036>] drm_mode_set_config_internal+0x66/0x100 [drm] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc009d5f8>] drm_mode_setcrtc+0x3a8/0x4c0 [drm] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc008e365>] drm_ioctl+0x125/0x610 [drm] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffffc009d250>] ? drm_mode_setplane+0x1b0/0x1b0 [drm] Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff811fffd5>] do_vfs_ioctl+0x285/0x470 Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff811ac159>] ? do_munmap+0x349/0x480 Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff81200239>] SyS_ioctl+0x79/0x90 Sep 06 16:16:35 benediktZ50-70 kernel: [<ffffffff817b6cf2>] entry_SYSCALL_64_fastpath+0x16/0x75 Sep 06 16:16:35 benediktZ50-70 kernel: ---[ end trace 724377a3c01e4270 ]--- I will check next week if these errors have any impact on my system. This is a Nvidia Optimus System with the Intel graphic card activated by default. ProblemType: Bug DistroRelease: Ubuntu 15.10 Package: linux-image-4.2.0-7-generic 4.2.0-7.7 ProcVersionSignature: Ubuntu 4.2.0-7.7-generic 4.2.0 Uname: Linux 4.2.0-7-generic x86_64 ApportVersion: 2.18-0ubuntu9 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: benedikt 1550 F.... pulseaudio /dev/snd/controlC1: benedikt 1550 F.... pulseaudio CurrentDesktop: KDE Date: Sun Sep 6 16:22:48 2015 HibernationDevice: UUID=3383b02e-b89c-462c-903a-cb936e81b2bf InstallationDate: Installed on 2014-12-21 (259 days ago) InstallationMedia: Kubuntu 15.04 "Vivid Vervet" - Alpha amd64 (20141218) MachineType: LENOVO 20354 ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-7-generic root=UUID=b549945a-67ac-4d14-849c-b54e561d47cc ro quiet splash vt.handoff=7 RelatedPackageVersions: linux-restricted-modules-4.2.0-7-generic N/A linux-backports-modules-4.2.0-7-generic N/A linux-firmware 1.147 SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 07/21/2015 dmi.bios.vendor: LENOVO dmi.bios.version: 9BCN91WW dmi.board.asset.tag: No Asset Tag dmi.board.name: Lancer 5A5 dmi.board.vendor: LENOVO dmi.board.version: 31900058WIN dmi.chassis.asset.tag: No Asset Tag dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Lenovo Z50-70 dmi.modalias: dmi:bvnLENOVO:bvr9BCN91WW:bd07/21/2015:svnLENOVO:pn20354:pvrLenovoZ50-70:rvnLENOVO:rnLancer5A5:rvr31900058WIN:cvnLENOVO:ct10:cvrLenovoZ50-70: dmi.product.name: 20354 dmi.product.version: Lenovo Z50-70 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1492764/+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