[drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in ips_enabled (expected 1, found 0)

[lorenzo.chianura]

[drm:intel_pipe_config_compare [i915]] *ERROR* mismatch in ips_enabled (expected 1, found 0)

in a kubuntu 15.10 x64 fresh installation, on a Lenovo z50-70 (intel HD4400/ nVidia 840M)

Not sure if it is related, but I'm experiencing lots of graphical glitches.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: linux-image-4.2.0-16-generic 4.2.0-16.19 [modified: boot/vmlinuz-4.2.0-16-generic]
ProcVersionSignature: Ubuntu 4.2.0-16.19-generic 4.2.3
Uname: Linux 4.2.0-16-generic x86_64
ApportVersion: 2.19.1-0ubuntu3
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: zero 1036 F.... pulseaudio
 /dev/snd/controlC1: zero 1036 F.... pulseaudio
Date: Sun Oct 25 12:33:41 2015
InstallationDate: Installed on 2015-10-25 (0 days ago)
InstallationMedia: Kubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
MachineType: LENOVO 20354
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-16-generic root=UUID=a66838c6-1843-42a4-8e49-808ff6df3d77 ro quiet splash vt.handoff=7
PulseList:
 Error: command ['pacmd', 'list'] failed with exit code 1: Home directory not accessible: Permission denied
 No PulseAudio daemon running, or not running as session daemon.
RelatedPackageVersions:
 linux-restricted-modules-4.2.0-16-generic N/A
 linux-backports-modules-4.2.0-16-generic N/A
 linux-firmware 1.149
SourcePackage: linux
UdevLog: Error: [Errno 2] No such file or directory: '/var/log/udev'
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 10/20/2014
dmi.bios.vendor: LENOVO
dmi.bios.version: 9BCN29WW
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:bvr9BCN29WW:bd10/20/2014: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

[lorenzo.chianura (zuloch)]

Thank you for the fast response.

As you have suggested I searched for a safe method to update my BIOS
without using Windows, following https://help.ubuntu.com/community/BIOSUpdate, but
it seems that there is not a "BIOS update CD" image for my laptop model.

So I will install Windows on my machine to safely perform the BIOS update
and then reinstall Kubuntu 15.10 so I can see if the fix worked.

[lorenzo.chianura (zuloch)]

I've just successfully updated the BIOS, but the problem is still here.

The output of sudo dmidecode -s bios-version give me:

9BCN91WW

and then sudo dmidecode -s bios-release-date give me:

07/21/2015

If it could be useful, I can attach a new dmesg log file, although I
found that excluded the line that describes the BIOS version, nothing has
changed.

[penalvch (penalvch)]

lorenzo.chianura, could you please test the latest upstream kernel available from the very top line at the top of the page from http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D (the release names are irrelevant for testing, and please do not test the daily folder)? Install instructions are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds . This will allow additional upstream developers to examine the issue.

If the latest kernel did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this issue is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description:
kernel-fixed-upstream
kernel-fixed-upstream-X.Y-rcZ

Where X, Y, and Z are numbers corresponding to the kernel version.

If the mainline kernel does not fix the issue, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-X.Y-rcZ

Please note, an error to install the kernel does not fit the criteria of kernel-bug-exists-upstream.

Once testing of the latest upstream kernel is complete, please mark this report's Status as Confirmed. Please let us know your results.

Thank you for your understanding.

[lorenzo.chianura (zuloch)]

Fixed in 4.3.0-040300rc7-generic.

[penalvch (penalvch)]

lorenzo.chianura, the next step is to fully reverse commit bisect from kernel 4.2 to 4.3-rc7 in order to identify the last bad commit, followed immediately by the first good one. Once this commit has been identified, then it may be reviewed as a candidate for backporting into your release. Could you please do this following https://wiki.ubuntu.com/Kernel/KernelBisection#How_do_I_reverse_bisect_the_upstream_kernel.3F ?

Please note, finding adjacent kernel versions is not fully commit bisecting.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs