[Dell M4800]: iwlwifi regularly loses connection on Intel 7260

[arty]

My problem seems to be different from #1315221 because it exists in 3.16.0-28-generic (Ubuntu 14.10)

About every 10 minutes my WiFi disconnects and a line like this appears in syslog:
Dec 23 21:58:36 work kernel: [ 1762.008441] wlan0: deauthenticated from 10:c6:1f:2c:49:56 (Reason: 7=CLASS3_FRAME_FROM_NONASSOC_STA)

Workarounds like 11n_disable=1 and `sudo modprobe -r iwlwifi; sudo modprobe iwlwifi` don't seem to help.

What helps is disabling network and enabling it again.

Another detail is that I don't remember seeing this problem at work where they use Cisco routers. I see the problem at home with my Speedport 723V Typ A router (a+b+n mode, WPA2).

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: linux-image-3.16.0-28-generic 3.16.0-28.38
ProcVersionSignature: Ubuntu 3.16.0-28.38-generic 3.16.7-ckt1
Uname: Linux 3.16.0-28-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.7-0ubuntu8
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: treguben 2595 F.... pulseaudio
 /dev/snd/controlC0: treguben 2595 F.... pulseaudio
CurrentDesktop: Unity
Date: Tue Dec 23 23:41:38 2014
HibernationDevice: RESUME=UUID=82445dd2-3bcf-42f7-ae59-4fba694e25de
InstallationDate: Installed on 2014-12-11 (12 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1)
MachineType: Dell Inc. Precision M4800
ProcFB: 0 EFI VGA
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-28-generic.efi.signed root=UUID=9a116abe-59b9-48b8-abe4-5064a191ac51 ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.16.0-28-generic N/A
 linux-backports-modules-3.16.0-28-generic N/A
 linux-firmware 1.138
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/02/2014
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A08
dmi.board.name: 0T3YTY
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA08:bd05/02/2014:svnDellInc.:pnPrecisionM4800:pvr01:rvnDellInc.:rn0T3YTY:rvrA00:cvnDellInc.:ct9:cvr:
dmi.product.name: Precision M4800
dmi.product.version: 01
dmi.sys.vendor: Dell Inc.

[Brad Figg (brad-figg)]

This change was made by a bot.

[arty (me-arty)]

I can also add that in the Connection Information dialog I see the speed frequently dropping to 1 or 5 Mb/s from 48 or 54

[penalvch (penalvch)]

arty, thank you for reporting this and helping make Ubuntu better. As per http://www.dell.com/support/home/us/en/19/product-support/product/precision-m4800-workstation/drivers an update to your computer's buggy and outdated BIOS is available (A11). If you update to this following https://help.ubuntu.com/community/BIOSUpdate does it change anything? If it doesn't, could you please both specify what happened, and provide the output of the following terminal command:
sudo dmidecode -s bios-version && sudo dmidecode -s bios-release-date

For more on BIOS updates and linux, please see https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette .

Please note your current BIOS is already in the Bug Description, so posting this on the old BIOS would not be helpful. As well, you don't have to create a new bug report.

Once the BIOS is updated, then please mark this report Status Confirmed.

Thank you for your understanding.

[arty (me-arty)]

After the BIOS upgrade the connection seems stable and it's speed doesn't change all the time. Thank you for the idea, Christopher! You've saved my Christmas :)

[penalvch (penalvch)]

arty, happy holidays, and I'm glad a BIOS update worked out for you. It's a common phenomenon here on Launchpad that many folks have all sorts of wonky hardware problems (myself included), and could have saved themselves going through the hassle of filing a bug report, or time consuming testing, before checking to see if a simple BIOS update addresses their issue.

However, as a BIOS update doesn't fit the criteria of the Fix Released Status as outlined in https://wiki.ubuntu.com/Bugs/Status (as a release from Ubuntu didn't fix this issue) I'll go ahead and mark this Invalid. However, if the problem returns, please file a new report (not reopen this one).

Thank you for your understanding, and please feel free to report any future bugs you may find.