kernel freeze related to rfcomm and maybe tty
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Undecided
|
Unassigned |
Bug Description
Kernel freezes for ~2 seconds after trying to access /dev/rfcommX device.
Steps to reproduce:
1. Edit /etc/bluetooth/
2. Issue "sudo rfcomm bind all" to create /dev/rfcomm0 device node.
3. Issue "cat /dev/rfcomm0" to trigger a bug.
Everything freezes (at least GUI): cursor does not move, no response from keypresses, no gui redraw for 2~3 seconds.
Then cat displays expected error message "cat: /dev/rfcomm0: Host is down" and system starts to respond again.
What expected (and occurs with 2.6.35) : no freeze between cat and error message.
Things goes worse when device, mentioned in /etc/bluetooth/
Bug may be introduced with recent changes to tty code to remove dependency on BKL. 2.6.36-rc1 shows this bug.
Will try development kernel with recent tty fixes and investigate further.
ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: linux-image-
Regression: Yes
Reproducible: Yes
ProcVersionSign
Uname: Linux 2.6.38-1-generic i686
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
AplayDevices:
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC272 Analog [ALC272 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
Architecture: i386
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC272 Analog [ALC272 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/
CRDA: Error: [Errno 2] Нет такого файла или каталога
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xf0340000 irq 43'
Mixer name : 'Realtek ALC272'
Components : 'HDA:10ec0272,
Controls : 19
Simple ctrls : 11
Date: Sun Feb 6 01:25:29 2011
HibernationDevice: RESUME=
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha i386 (20110202)
MachineType: SAMSUNG ELECTRONICS CO., LTD. NC10
ProcEnviron:
LANGUAGE=
LANG=ru_RU.UTF-8
LC_MESSAGES=
SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=
RelatedPackageV
linux-
linux-
linux-firmware 1.46
SourcePackage: linux
dmi.bios.date: 09/08/2009
dmi.bios.vendor: Phoenix Technologies Ltd.
dmi.bios.version: 11CA.M015.
dmi.board.name: NC10
dmi.board.vendor: SAMSUNG ELECTRONICS CO., LTD.
dmi.board.version: Not Applicable
dmi.chassis.
dmi.chassis.type: 10
dmi.chassis.vendor: SAMSUNG ELECTRONICS CO., LTD.
dmi.chassis.
dmi.modalias: dmi:bvnPhoenixT
dmi.product.name: NC10
dmi.product.
dmi.sys.vendor: SAMSUNG ELECTRONICS CO., LTD.
Attached patch fixes this bug.