After an upgrade to Ubuntu 10.10 the previously natively-supported Fn key control of backlight brightness is gone. I can control backlight with xbacklight, as before.
Models of notebook affected include Sony Vaio SZ4 and SZ6.
Git bisect locates the bug to commit bcbfc24ead6935714a001ab6f1f725763075f98c
in Maverick's kernel branch
http://kernel.ubuntu.com/git?p=ubuntu/ubuntu-maverick.git;a=summary
This bug has been fixed in Linus' mainline, commit de391d12500ede13faa7ecadbe900a8de1f76cfa
ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: acpi-support 0.137
ProcVersionSignature: Ubuntu 2.6.35-22.33-generic 2.6.35.4
Uname: Linux 2.6.35-22-generic x86_64
Architecture: amd64
Date: Mon Oct 11 11:21:39 2010
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100412)
ProcEnviron:
LANG=en_GB.utf8
SHELL=/bin/bash
SourcePackage: acpi-support
---
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
AplayDevices:
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
Architecture: amd64
ArecordDevices:
**** List of CAPTURE Hardware Devices ****
card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: mdoube 1739 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
Card hw:0 'Intel'/'HDA Intel at 0xfc500000 irq 48'
Mixer name : 'SigmaTel STAC9872AK'
Components : 'HDA:83847662,104d1e00,00100201 HDA:14f12c06,104d1700,00100000'
Controls : 11
Simple ctrls : 7
DistroRelease: Ubuntu 10.10
HibernationDevice: RESUME=UUID=a017c7e4-4a29-4ba1-bfea-52cd609781d8
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100412)
MachineType: Sony Corporation VGN-SZ650N
Package: linux (not installed)
PccardctlIdent:
Socket 0:
no product info available
PccardctlStatus:
Socket 0:
no card
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-22-generic root=UUID=31cf7381-5708-4104-8d9e-a2eaaec7cbe7 ro quiet splash
ProcEnviron:
PATH=(custom, no user)
LANG=en_GB.utf8
SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.35-22.33-generic 2.6.35.4
Regression: Yes
RelatedPackageVersions: linux-firmware 1.38
Reproducible: Yes
RfKill:
0: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
Tags: maverick kernel-graphics regression-release needs-upstream-testing
Uname: Linux 2.6.35-22-generic x86_64
UserGroups:
dmi.bios.date: 04/04/2008
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: R0122S5
dmi.board.asset.tag: N/A
dmi.board.name: VAIO
dmi.board.vendor: Sony Corporation
dmi.board.version: N/A
dmi.chassis.type: 10
dmi.chassis.vendor: Sony Corporation
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvrR0122S5:bd04/04/2008:svnSonyCorporation:pnVGN-SZ650N:pvrJ002UR2M:rvnSonyCorporation:rnVAIO:rvrN/A:cvnSonyCorporation:ct10:cvrN/A:
dmi.product.name: VGN-SZ650N
dmi.product.version: J002UR2M
dmi.sys.vendor: Sony Corporation
---
Architecture: amd64
DistroRelease: Ubuntu 10.10
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100412)
Package: linux (not installed)
ProcEnviron:
PATH=(custom, no user)
LANG=en_GB.utf8
SHELL=/bin/bash
Tags: maverick
Uname: Linux 2.6.36-rc7-linusgit-1.0+ x86_64
UnreportableReason: The running kernel is not an Ubuntu kernel
UserGroups:
Bug not present if I boot with last 10.04 kernel, which was left as an option in my Grub menu. Reassigning to Linux as a kernel issue.