kernel-packages team mailing list archive

["Christopher M. Penalver" <christopher.m.penalver@xxxxxxxxx>]

Danny Edel, thank you for reporting this and helping make Ubuntu better.

Please execute the following command, as it will automatically gather debugging information, in a terminal:
apport-collect 1471530

** Package changed: linux-lts-utopic (Ubuntu) => linux (Ubuntu)

** Changed in: linux (Ubuntu)
   Importance: Undecided => Low

** Changed in: linux (Ubuntu)
       Status: New => Incomplete

-- 
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/1471530

Title:
  Acer Aspire 5315: Fan turns off when loading linux, resulting in
  system overheat and emergency shutdown

Status in linux package in Ubuntu:
  Incomplete

Bug description:
  First off: I'm running Ubuntu 14.04.2 LTS "Trusty Tahr", yet ubuntu-
  bug linux started the bug report against linux-lts-utopic. I hope it
  knows what it's doing : )

  uname -a says "Linux aspire5315 3.16.0-41-generic #57~14.04.1-Ubuntu
  SMP Thu Jun 18 18:01:13 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux".

  Now to the problem.
  The fan on this particular Laptop seems to be either controlled by BIOS or - after the operating system signals somehow(tm) that it's capable of doing so - completely by software. There is (I assume it's implemented in the mainboard firmware) an emergency-power-off once the temperature exceeds a certain threshold, that's what causing the sudden poweroff after a while.

  Without any modifications, if you power it up (assuming its already
  warm from a previous session), the fan works correctly. If you load
  BIOS or GRUB, no problems. I could confirm temperature-dependent
  control works by loading a memtest86 and letting it run for a few
  hours; Fan speed kept going up and down, machine did not crash.

  Once you load a linux kernel (LiveCD exhibits the same behaviour), the
  fan stops completely and the system starts heating up. I was able to
  get through a complete ubuntu installation before poweroff by not
  using an internet connection and clicking defaults as fast as
  possible, starting with the machine cold.

  After I had ubuntu installed, thanks to much help at bug report
  #728733 I have made the following discoveries.

  (1) Booting linux with "acpi=off" results in a kernel panic (I had to replace "quiet splash" with "verbose" to see that), but the fan stays on.
  (2) Booting linux with "acpi=off noapic" or "acpi=off nolapic" results in the fan working correctly, but the wifi card doen't work.
  (3) Booting linux normally, if you monitor /sys/class/thermal/thermal_zone0/temp it stays at 40000 (40°C) even if lm-sensors' coretemp tells me that the processor is quite beyond that. [note: It is possible that the fan is just so quiet at the 40°C setting that I'm thinking its off]. Thermald also seems to depend on this temperature reading and therefore does not throttle the CPU.
  (4) Sending the machine to standby and waking it up again results in the thermal_zone0/temp getting updated regularly (it seems to follow coretemp with a few seconds lag) and the fan turning faster and slower. In this state, the system is perfectly usable.

  What I would like is to have the system in state 4 (fan turning and
  adjusting to temperature) without requiring human intervention, either
  by avoiding the fan stopping in the first place (preferred) or by re-
  starting it automated sometime in the boot process.

  > We also need:
  1) The release of Ubuntu you are using
  'lsb_release -rd' gives
  Description:	Ubuntu 14.04.2 LTS
  Release:	14.04

  2) The version of the package you are using
  'apt-cache policy linux-image-$(uname -r)' says I'm running
  3.16.0-41.57~14.04.1

  3) What you expected to happen
  System fan stays on after grub->linux handoff (or only stays off for a brief time period and comes back up automatically)

  4) What happened instead
  System fan stays off until I suspend and wakeup the machine, possibly resulting in heat emergency poweroff if I am too slow or forget to do it

  ProblemType: Bug
  DistroRelease: Ubuntu 14.04
  Package: linux-image-3.16.0-41-generic 3.16.0-41.57~14.04.1
  ProcVersionSignature: Ubuntu 3.16.0-41.57~14.04.1-generic 3.16.7-ckt11
  Uname: Linux 3.16.0-41-generic x86_64
  ApportVersion: 2.14.1-0ubuntu3.11
  Architecture: amd64
  CurrentDesktop: Unity
  Date: Sun Jul  5 12:16:55 2015
  InstallationDate: Installed on 2001-01-02 (5296 days ago)
  InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64+mac (20150218.1)
  SourcePackage: linux-lts-utopic
  UpgradeStatus: No upgrade log present (probably fresh install)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1471530/+subscriptions