@Stephen Gutknecht, it looks like that bug report could be the same. I am not using the "intel_idle.max_cstate=1" workaround as that is only a hack of a solution and not designed for long term use. Many with the same architecture as me and with the same problems have reported that fix seems to work well for them, but since it requires fiddling with grub and prevents freezing at the expense of increased CPU heat i have avoided it. I would rather try and spend the effort to try and help get a real fix in the works, but i'll be honest in saying i'm not sure any progress has been made and/or if i am really helping.
But your right, compared to most kernel problems this one does not even give a kernel panic indicator or any watchdog, so that is unsettling. The kernel i've been using when i absolutely can't afford a freeze is still my trusty 3.16 kernel. A potential work around for the school guy (Rüdiger Kupper) could be to upgrade his systems, but then downgrade the kernel to 3.16 and remove any newer ones and disable updates. But that's not a great solution either, but it should work. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to the bug report. https://bugs.launchpad.net/bugs/1575467 Title: [Dell Inspiron 3451] WARNING: CPU: 1 PID: 1297 at /build/linux-lts- utopic-vy2yyy/linux-lts- utopic-3.16.0/drivers/gpu/drm/i915/intel_display.c:1743 vlv_wait_port_ready+0x126/0x170 [i915]() Status in linux package in Ubuntu: In Progress Status in linux source package in Xenial: In Progress Bug description: After upgrading from stock Ubuntu 14.04 to 16.04 my laptop consistently freezes up and is unresponsive to keyboard or mouse. The only way is to do a hard shutdown. I'm usually in a browser when this happens, and often watching a video or two. It seems to happen more often in Google Chrome than Firefox, but it happens with both. It has happened at least once with no videos loaded. I haven’t observed it freeze / hang when I’m not in a browser, but that's mainly what i use my laptop for, so that's where most of my time is spent. Call trace: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1575467/+attachment/4648682/+files/kern.log.2.gz --- ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: andrew 1949 F.... pulseaudio DistroRelease: Ubuntu 16.04 HibernationDevice: RESUME=UUID=e8aaee7c-d956-4519-94f0-cf7aad745020 InstallationDate: Installed on 2015-08-08 (263 days ago) InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1) MachineType: Dell Inc. Inspiron 3451 Package: linux (not installed) ProcEnviron: LANGUAGE=en_US TERM=xterm-256color PATH=(custom, no user) LANG=en_US.UTF-8 SHELL=/bin/bash ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-21-generic.efi.signed root=UUID=d01f07be-c906-4024-8eef-a58ba3935298 ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6 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-4.4.0-21-generic N/A linux-backports-modules-4.4.0-21-generic N/A linux-firmware 1.157 Tags: xenial Uname: Linux 4.4.0-21-generic x86_64 UpgradeStatus: Upgraded to xenial on 2016-04-22 (4 days ago) UserGroups: _MarkForUpload: True dmi.bios.date: 12/05/2014 dmi.bios.vendor: Dell Inc. dmi.bios.version: A00 dmi.board.name: 0H4MK6 dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: Not Specified dmi.modalias: dmi:bvnDellInc.:bvrA00:bd12/05/2014:svnDellInc.:pnInspiron3451:pvrA00:rvnDellInc.:rn0H4MK6:rvrA00:cvnDellInc.:ct8:cvrNotSpecified: dmi.product.name: Inspiron 3451 dmi.product.version: A00 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1575467/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp

