lirc_ite8709 kernel module failure on suspend/resume
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Expired
|
Undecided
|
Unassigned |
Bug Description
This bug has been present in all version of Ubuntu since at least version ubuntu 9.10.
The lirc_ite8709 kernel module exhibits an incorrect behaviour on suspend/resume of a laptop. It sends lots of interruptions, which results in acpi sending even more interruptions, which also results in kernel scheduler sending even more interruptions.
All this flood of interruptions saturates ksoftirqd.
So the symptoms are simple: when using a device supported by lirc_ite8709 (i.e. an infrared receiver):
- suspend the laptop
- resume it
- observe that ksoftirqd uses 98-100% of one CPU core, unless you reboot your computer
The only work-around I've been able to find to avoid this behaviour is to disable the module by adding the following line in /etc/modprobe.
blacklist lirc_ite8709
ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: linux-image-
Regression: No
Reproducible: Yes
ProcVersionSign
Uname: Linux 2.6.35-19-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
Architecture: i386
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: CONEXANT Analog [CONEXANT Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xf4600000 irq 48'
Mixer name : 'Conexant CX20549 (Venice)'
Components : 'HDA:14f15045,
Controls : 18
Simple ctrls : 8
Date: Sun Sep 5 22:09:41 2010
HibernationDevice: RESUME=
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Beta i386 (20100901.1)
MachineType: Packard Bell BV EasyNote MB85
ProcCmdLine: BOOT_IMAGE=
ProcEnviron:
LANG=fr_FR.utf8
SHELL=/bin/bash
RelatedPackageV
RfKill:
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
SourcePackage: linux
dmi.bios.date: 08/01/2007
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: PB2A3A07
dmi.board.name: PB2A
dmi.board.vendor: Packard Bell BV
dmi.board.version: Not Applicable
dmi.chassis.
dmi.chassis.type: 1
dmi.chassis.vendor: Packard Bell BV
dmi.chassis.
dmi.modalias: dmi:bvnPhoenixT
dmi.product.name: EasyNote MB85
dmi.product.
dmi.sys.vendor: Packard Bell BV
description: | updated |
Changed in linux (Ubuntu): | |
status: | New → Confirmed |
The following file contains the ProcInterrupts output when the problem occurs.
Notice that lirc_ite8709 interrupts are more important one one core (and this was just a few seconds after the laptop woke-up, this gets worse as time passes), even though no use of the IR receiver is made.