Touchpad lock button locks mouse completely on Acer Aspire 7540

[MrRomanze]

Then I click touchpad lock button, it works, button glows, notification shows up, mouse locks.
However, then I press it again, it wouldn't unlock the touchpad. (but button stops to glow and notifications shows up again too)
The only solution is to reboot.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: linux-image-4.2.0-25-lowlatency 4.2.0-25.30
ProcVersionSignature: Ubuntu 4.2.0-25.30-lowlatency 4.2.6
Uname: Linux 4.2.0-25-lowlatency x86_64
ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: potato 2548 F.... pulseaudio
 /dev/snd/controlC1: potato 2548 F.... pulseaudio
CurrentDesktop: Unity
Date: Tue Jan 26 20:29:28 2016
HibernationDevice: RESUME=UUID=2277e00a-0411-4136-b180-2892752df2e0
InstallationDate: Installed on 2016-01-17 (9 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
MachineType: Acer Aspire 7540
ProcFB: 0 radeondrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.2.0-25-lowlatency root=UUID=ae6c8d51-38da-4c25-9281-6b9ceac5b2ca ro quiet splash acpi_sleep=nonvs quiet splash acpi_sleep=nonvs vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-4.2.0-25-lowlatency N/A
 linux-backports-modules-4.2.0-25-lowlatency N/A
 linux-firmware 1.149.3
SourcePackage: linux
UdevLog: Error: [Errno 2] Нет такого файла или каталога: '/var/log/udev'
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/07/2009
dmi.bios.vendor: Phoenix Technologies LTD
dmi.bios.version: V1.11
dmi.board.name: JV71TR
dmi.board.vendor: Acer
dmi.board.version: Rev
dmi.chassis.type: 10
dmi.chassis.vendor: Acer
dmi.chassis.version: None
dmi.modalias: dmi:bvnPhoenixTechnologiesLTD:bvrV1.11:bd12/07/2009:svnAcer:pnAspire7540:pvr0100:rvnAcer:rnJV71TR:rvrRev:cvnAcer:ct10:cvrNone:
dmi.product.name: Aspire 7540
dmi.product.version: 0100
dmi.sys.vendor: Acer

[Brad Figg (brad-figg)]

This change was made by a bot.

[penalvch (penalvch)]

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

To clarify, is this reproducible with the generic kernel?

[MrRomanze (mrromanze)]

Yes, this happens with generic kernel too.

Note: I'm now on 16.04. (4.3.0.7.8)

[penalvch (penalvch)]

MrRomanze, in order to allow additional upstream developers to examine the issue, at your earliest convenience, could you please test the latest upstream kernel available from http://kernel.ubuntu.com/~kernel-ppa/mainline/?C=N;O=D ? Please keep in mind the following:
1) The one to test is at the very top line at the top of the page (not the daily folder).
2) The release names are irrelevant.
3) The folder time stamps aren't indicative of when the kernel actually was released upstream.
4) Install instructions are available at https://wiki.ubuntu.com/Kernel/MainlineBuilds .

If testing on your main install would be inconvenient, one may:
1) Install Ubuntu to a different partition and then test this there.
2) Backup, or clone the primary install.

If the latest kernel did not allow you to test to the issue (ex. you couldn't boot into the OS) please make a comment in your report about this, and continue to test the next most recent kernel version until you can test to the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this issue is fixed in the mainline kernel, please add the following tags by clicking on the yellow circle with a black pencil icon, next to the word Tags, located at the bottom of the report description:
kernel-fixed-upstream
kernel-fixed-upstream-X.Y-rcZ

Where X, and Y are the first two numbers of the kernel version, and Z is the release candidate number if it exists.

If the mainline kernel does not fix the issue, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-X.Y-rcZ

Please note, an error to install the kernel does not fit the criteria of kernel-bug-exists-upstream.

Once testing of the latest upstream kernel is complete, please mark this report's Status as Confirmed. Please let us know your results.

Thank you for your understanding.

[MrRomanze (mrromanze)]

This happens on latest upstream kernel too. ( 4.5.0-040500rc1-generic )

[penalvch (penalvch)]

MrRomanze:
1) Did this problem not occur in a release prior to Wily?
2) If you remove the non-default kernel parameter acpi_sleep=nonvs does this have an impact?

[MrRomanze (mrromanze)]

1) No idea, I haven't tested it on older releases. BUT, it happens on 16.04!
2) No impact.