8086:08b1 (rev 6b) [Dell XPS 13 9333] iwlwifi regularly loses connection/becomes unusable on Intel 7260

[Ethan Blanton]

My Intel 7260 network card regularly shows very poor performance and/or loses its connection entirely. On several occasions I have been unable to reestablish an association with the AP without rebooting. This occurs even if the laptop is within a few feet of the AP. I did not have this problem on 12.04 with a quantal backport kernel.

Network controller [0280]: Intel Corporation Wireless 7260 [8086:08b1] (rev 6b)
Subsystem: Intel Corporation Dual Band Wireless-AC 7260 [8086:c470]

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: linux-image-3.13.0-24-generic 3.13.0-24.46
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
Date: Thu May 1 22:59:32 2014
HibernationDevice: RESUME=/dev/mapper/cswap0
InstallationDate: Installed on 2014-04-25 (6 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
MachineType: Dell Inc. XPS13 9333
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-24-generic root=/dev/mapper/root ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-24-generic N/A
 linux-backports-modules-3.13.0-24-generic N/A
 linux-firmware 1.127
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/11/2013
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A02
dmi.board.name: 0GFTRT
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: 0.1
dmi.modalias: dmi:bvnDellInc.:bvrA02:bd12/11/2013:svnDellInc.:pnXPS139333:pvr:rvnDellInc.:rn0GFTRT:rvrA00:cvnDellInc.:ct8:cvr0.1:
dmi.product.name: XPS13 9333
dmi.sys.vendor: Dell Inc.
---
ApportVersion: 2.14.1-0ubuntu3.2
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: elb 5375 F.... pulseaudio
 /dev/snd/controlC0: elb 5375 F.... pulseaudio
DistroRelease: Ubuntu 14.04
HibernationDevice: RESUME=/dev/mapper/cswap0
InstallationDate: Installed on 2014-04-25 (94 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
MachineType: Dell Inc. XPS13 9333
Package: linux (not installed)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-32-generic root=/dev/mapper/root ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 3.13.0-32.57-generic 3.13.11.4
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-32-generic N/A
 linux-backports-modules-3.13.0-32-generic N/A
 linux-firmware 1.127.5
Tags: trusty
Uname: Linux 3.13.0-32-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip libvirtd lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 03/19/2014
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A04
dmi.board.name: 0GFTRT
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: 0.1
dmi.modalias: dmi:bvnDellInc.:bvrA04:bd03/19/2014:svnDellInc.:pnXPS139333:pvr:rvnDellInc.:rn0GFTRT:rvrA00:cvnDellInc.:ct8:cvr0.1:
dmi.product.name: XPS13 9333
dmi.sys.vendor: Dell Inc.

[Brad Figg (brad-figg)]

This change was made by a bot.

[Ethan Blanton (eblanton)]

The new BIOS info:

A04
03/19/2014

I am running the new BIOS now, and will report back as to condition changes.

[Ethan Blanton (eblanton)]

No change with the new BIOS.

[penalvch (penalvch)]

Ethan Blanton, could you please test the latest upstream kernel available (not the daily folder) following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested. If this bug is fixed in the mainline kernel, please add the following tags:
kernel-fixed-upstream
kernel-fixed-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested. For example:
kernel-fixed-upstream-3.15-rc3

This can be done by clicking on the yellow circle with a black pencil icon next to the word Tags located at the bottom of the bug description. As well, please remove the tag:
needs-upstream-testing

If the mainline kernel does not fix this bug, please add the following tags:
kernel-bug-exists-upstream
kernel-bug-exists-upstream-VERSION-NUMBER

As well, please remove the tag:
needs-upstream-testing

Once testing of the upstream kernel is complete, please mark this bug's Status as Confirmed. Please let us know your results. Thank you for your understanding.

[Ethan Blanton (eblanton)]

It will take some time to know for sure as the problem is intermittent, so I'm not going to update tags just yet, but I have been on 3.15.0-031500rc3-generic for about 24h now with no dropouts or slowdowns. This kernel is looking promising.

Unfortunately it has a regression in that the touchpad doesn't multitouch, but I guess we'll address that separately if it becomes necessary. I don't know if that's due to missing ubuntu patches or driver changes or what.

[Ethan Blanton (eblanton)]

This problem appears to be fixed in 3.15.0-rc3. I have not had a wifi drop in more than 36 hours. Additionally, the reported wireless signal strength doesn't bounce around wildly.

[Youresorock (youresorock)]

I just tried with 3.15.0-rc4 and the problem is still there. Wifi dropped out 1% into 20MB wget test.

[penalvch (penalvch)]

Youresorock, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Youresorock (youresorock)]

Christopher, I ended up installing 3.11 mainline: http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.11.10.9-saucy/

This solved the issue entirely. I had to uninstall the ubuntu 3.13 kernel to ensure the system won't default back, so I won't be able to run that report. I didn't try 3.12 because I knew the system worked fine on 3.11 previously and I ran out of time.

[penalvch (penalvch)]

Youresorock, one may report a new bug report via a Live environment. Please make any further comments in the new bug report you make.

Thank you for your understanding.

[Ethan Blanton (eblanton)]

Since Youresorock reported problems with 3.15.0rc4, I tried it on my laptop -- it seems to work as well as 3.15.0rc3.

I may try a saucy kernel if it also works, because the lack of multitouch on the trackpad in 3.15 is maddening!

[Benjamin Winston (dolemite)]

I put 14.04 on my HP Pavilion DM1 and noticed this failure immediately. I'll try the different kernel versions mentioned in this thread and report results.

[Sam Lin (itrs-lin)]

no luck for linux-image-3.11.10-03111009-generic and linux-image-3.15.0-031500rc2-generic.

tested on Lenovo IdeaPad U330P.

[Sam Lin (itrs-lin)]

there is a firmware for 3.14+ kernel :
(iwlwifi-7260-ucode-22.212.9.0.tgz)

http://wireless.kernel.org/en/users/Drivers/iwlwifi

tested on linux-image-3.15.0-031500rc2-generic with Lenovo IdeaPad U330P, not working.

[penalvch (penalvch)]

Benjamin Winston / Sam Lin, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Benjamin Winston (dolemite)]

Hi Chris, I submitted the bug, and attached it to the existing bug. Let me
know if I can help out.

Ben

On Fri, May 9, 2014 at 6:22 PM, Christopher M. Penalver <
<email address hidden>> wrote:

> Benjamin Winston / Sam Lin, thank you for your comment. So your hardware
> and problem may be tracked, could you please file a new report with Ubuntu
> by executing the following in a terminal while booted into a Ubuntu
> repository kernel (not a mainline one) via:
> ubuntu-bug linux
>
> For more on this, please read the official Ubuntu documentation:
> Ubuntu Bug Control and Ubuntu Bug Squad:
> https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
> Ubuntu Kernel Team:
> https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
> Ubuntu Community:
> https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette
>
> When opening up the new report, please feel free to subscribe me to it.
>
> Thank you for your understanding.
>
> Helpful bug reporting tips:
> https://wiki.ubuntu.com/ReportingBugs
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1315221
>
> Title:
> 8086:08b1 [Dell XPS 13 9333] iwlwifi regularly loses
> connection/becomes unusable on Intel 7260
>
> Status in “linux” package in Ubuntu:
> Confirmed
>
> Bug description:
> My Intel 7260 network card regularly shows very poor performance
> and/or loses its connection entirely. On several occasions I have been
> unable to reestablish an association with the AP without rebooting.
> This occurs even if the laptop is within a few feet of the AP. I did
> not have this problem on 12.04 with a quantal backport kernel.
>
> ProblemType: Bug
> DistroRelease: Ubuntu 14.04
> Package: linux-image-3.13.0-24-generic 3.13.0-24.46
> ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
> Uname: Linux 3.13.0-24-generic x86_64
> ApportVersion: 2.14.1-0ubuntu3
> Architecture: amd64
> Date: Thu May 1 22:59:32 2014
> HibernationDevice: RESUME=/dev/mapper/cswap0
> InstallationDate: Installed on 2014-04-25 (6 days ago)
> InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64
> (20140417)
> MachineType: Dell Inc. XPS13 9333
> ProcFB: 0 inteldrmfb
> ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.13.0-24-generic
> root=/dev/mapper/root ro quiet splash vt.handoff=7
> RelatedPackageVersions:
> linux-restricted-modules-3.13.0-24-generic N/A
> linux-backports-modules-3.13.0-24-generic N/A
> linux-firmware 1.127
> SourcePackage: linux
> UpgradeStatus: No upgrade log present (probably fresh install)
> dmi.bios.date: 12/11/2013
> dmi.bios.vendor: Dell Inc.
> dmi.bios.version: A02
> dmi.board.name: 0GFTRT
> dmi.board.vendor: Dell Inc.
> dmi.board.version: A00
> dmi.chassis.type: 8
> dmi.chassis.vendor: Dell Inc.
> dmi.chassis.version: 0.1
> dmi.modalias:
> dmi:bvnDellInc.:bvrA02:bd12/11/2013:svnDellInc.:pnXPS139333:pvr:rvnDellInc.:rn0GFTRT:rvrA00:cvnDellInc.:ct8:cvr0.1:
> dmi.product.name: XPS13 9333
> dmi.sys.vendor: Dell Inc.
>
> To manage notifications abou...

[Craig (craigtlandry)]

I'm also having this problem and found a matching bug over on the kernel bug tracker:
https://bugzilla.kernel.org/show_bug.cgi?id=72601

Emmanuel Grumbach (Intel wifi driver maintainer) is helping with the issue.

[penalvch (penalvch)]

Craig, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[asala (asala)]

XPS13 wifi behaviour seems to be much better on Linux kernel 3.15.2 from the mainline ubuntu ppa: I was working for 2 hours and had only one disconnection. http://www.yourownlinux.com/2014/06/how-to-install-upgrade-to-linux-kernel-3-15-2-in-linux.html

Running 3.15.3 gave me no disconnections but very low bandwidth (might be just by chance, only tested for 30 mins, very far away from the router).

Note 1: In exchange for better wifi, I lost touch gestures on the touchpad (https://bugs.archlinux.org/task/40921?project=1&openedfrom=-1+week), as "blacklist i2c_hid" had to be removed in order for it to be detected (both on 3.15.2 and 3.15.3). Maybe testing on the latest 3.14 kernel might be good to have reliable wifi plus full touchpad support. I jumped directly to 3.15.2 so I cannot report on it.

[penalvch (penalvch)]

asala, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into a Ubuntu repository kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[penalvch (penalvch)]

Ethan Blanton, the next step is to fully reverse bisect the kernel in order to identify the fix commit. Could you please do this following https://wiki.ubuntu.com/Kernel/KernelBisection#How_do_I_reverse_bisect_the_upstream_kernel.3F ?

[Ethan Blanton (eblanton)]

I can. This will take me some time, as the problem does not necessarily show up immediately. It is also somewhat better (though not entirely fixed) in 3.13.0-30 compared to 3.13.0-24, under which this was reported. (The connection still drops frequently, but it seems to recover much more quickly, and I have not had to reboot due to a total failure to recover in quite some time.)

I believe the bisection will be between 3.8 and 3.13, so there are quite a few kernels to cover in between.

[asala (asala)]

From the upstream kernel bug, it seems that fixes for bad iwlwifi 7260 behaviour upstream are in 3.14.6
 https://bugzilla.kernel.org/show_bug.cgi?id=72601#c92
and, a second fix in https://bugzilla.kernel.org/show_bug.cgi?id=42978#c29
will land upstream shortly.
If these fixes are causing xps 13 wifi issues, it does not seem that bisecting 3.13 will be too helpful.
Anyway, I'm not too knowledgeable on bisection and patch backporting.

[Ethan Blanton (eblanton)]

asala: While it's known that there are forward fixes, it also worked in an earlier kernel. This means that there is previous breakage, as well. The fixes may be for that same breakage, I haven't looked into that.

I believe 3.16 is fixed, as well.

[Seth Forshee (sforshee)]

Ethan: We recently incorporated some updates in 14.04 specifically for disconnection issues with Intel 7260 wireless. Could you ensure your system is fully up to date, reboot (ensuring that you use the official 3.13 kernel for trusty and not any newer version you installed for testing), and let me know if the situation improves? If not we can start trying to figure out what changes from newer kernel versions fix your issues.

Everyone else: unless you have the exact same machine as Ethan has, please file a new bug report if you haven't already by running 'ubuntu-bug linux' from a terminal. Feel free to subscribe me to your bug reports.

Thanks!

[Ethan Blanton (eblanton)]

Seth: I am currently running, and have been running for a couple of days, linux-image-3.13.0-32-generic and linux-firmware 1.127.5. I was in fact going to post here that performance seems to be *worse* than it had been for some time; three times recently my laptop has lost its wifi association and been unable to reassociate with *any* AP until it has been rebooted.

Regarding the upstream kernels (from a previous thread of inquiry), I have confirmed that no kernels older than 3.10 work at all, and it appears that all kernels newer than 3.10.47 and older than 3.15 display this problem in some fashion or another. I haven't yet tested 3.10.0 through 3.10.46 to determine if any of them work properly. It looks like my 12.04 + backports maybe only worked due to patches(?).

[Seth Forshee (sforshee)]

Thanks for the update. I've got a couple things I'd like you to try next.

First, when you've booted to 3.13.0-32, wait until you are no longer able to associate. Then if you have access to a wired connection, run 'apport-collect 1315221' to attach logs from that kernel. If you don't have a wired connection, try running 'sudo modprobe -r iwlwifi; modprobe iwlwifi' and see if you can associate. If your connection is working, run apport-collect. Otherwise reboot and run apport-collect before your connection gets bad.

Then I'd like to narrow down where before 3.14 and 3.15 your problems are fixed. Please try the 3.15-rc mainline builds and let me know which is the first one that fixes your problems. I know this is kind of a pain, but if the problem is already fixed in newer kernels the easiest thing to do is usually figure out what change fixes it.

Thanks!

[Ethan Blanton (eblanton)]

apport information

[Ethan Blanton (eblanton)]

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[Ethan Blanton (eblanton)]

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[Ethan Blanton (eblanton)]

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[Ethan Blanton (eblanton)]

This apport collect is after an association failure this morning; the machine was rebooted about two hours ago and has been associated since. If that is too long after reboot, let me know and I'll collect another set of data. This machine has no wired Ethernet and I do not have a USB dongle. Reloading iwlwifi has worked only intermittently in the past, although I have not tried it in the past couple of days.

Upstream 3.15.0-rc3 was the first upstream post-3.13 to work completely stable for me. As I recall, 3.15 in general was much better than 3.13, but -rc1 and -rc2 had some lingering issues. I don't know if current upstream 3.15.x kernels work, although I can check that if you like. They are not suitable for long term use as the touchpad does not work correctly with their module complement.

[Seth Forshee (sforshee)]

Those logs are only showing me what happened since the last boot. If you can hunt down the syslog in /var/log which has that boot then that might help.

Actually, what would be even better would be if you could download http://people.canonical.com/~sforshee/wifi-debug, make it executable, then start running it (./wifi-debug -t). Then just leave it until you start seeing problems, press Enter to stop it, and give me the wifi-debug-files.tar.gz file that it creates. This file may be quite large if it runs for a while, and it could also contain some small amount of private data, so it's better not to attach it to the bug. You can email it to me if it's not too big, or if you have access to some online storage you could upload it there and send me a link. You might also stop/restart it periodically if you're connection is working well to help keep it from getting too big.

From what you said about the mainline builds, it sounds like there wasn't a single kernel version where everything got fixed. You say 3.15-rc1 was better and 3.15-rc3 was better still - did you ever test the final release of 3.14? I'd like to know whether the improvement happened between 3.14 and 3.15-rc1 or if it happened somewhere in 3.14.

[Seth Forshee (sforshee)]

Hmm, it's odd that you would have seen any difference between 3.15 rc2 and rc3, as there are no changes at all to any networking code or wireless drivers between those releases. I can't find anything that looks like it should have had any impact on the stability of your wireless connection.

[Ethan Blanton (eblanton)]

That is the same conclusion I came to at the time, that it made no sense. I wondered if linux-firmware didn't change somewhere in there. As I recall, 3.13 uses the -8 firmware, and 3.15 used the -9, and I wondered if -9 might have been updated. I can retry 3.15.0-rc1 -rc2 -rc3 if that would be helpful to you.

[Seth Forshee (sforshee)]

Yes, -9 is supported as of 3.15-rc2 (though it should also be supported in the 3.14 stable updates as well). I don't recall any updates to -9, but it was added to linux-firmware in trusty at some point, so if you did any other updates in between testing rc2 and rc3 it's possible you also changed to newer firmware. So it might not hurt to test rc2 and rc3 again, after you collect the wifi-debug data of course ;-)

[Ethan Blanton (eblanton)]

OK, I've had time to triage wifi-debug (sorry, but I'm sure you understand!), and it is now running. This failure takes between a few minutes to several hours to emerge; I will almost certainly see wifi dropouts in the next few hours, but it may or may not lose association entirely for a very long time. We shall see. If I have a rocky patch I'll go ahead and send the log, and if that's not sufficient we'll try to make sure to get a total association loss.

Regarding kernel versions; it sounds like you'd like me to test 3.14 (current) as well as 3.15-rc2 and 3.15-rc3? To clarify, 3.15-rc3 worked without any issues for several days, so I believe the problem to be entirely fixed there. The issues that drove me back to 3.13 were regarding other hardware, not wifi. :-) Are you still interested in older kernels? Unless you have another specific preference, I'll try 3.15-rc2 next. If it works, I can try 3.15-rc1, and if not, 3.15-rc3.

A lightly redacted syslog for what appears to be a number of failure events is attached.

[Seth Forshee (sforshee)]

On Tue, Jul 29, 2014 at 08:41:36PM -0000, Ethan Blanton wrote:
> Regarding kernel versions; it sounds like you'd like me to test 3.14
> (current) as well as 3.15-rc2 and 3.15-rc3? To clarify, 3.15-rc3 worked
> without any issues for several days, so I believe the problem to be
> entirely fixed there. The issues that drove me back to 3.13 were
> regarding other hardware, not wifi. :-) Are you still interested in
> older kernels? Unless you have another specific preference, I'll try
> 3.15-rc2 next. If it works, I can try 3.15-rc1, and if not, 3.15-rc3.

I'm really just wanting to know when things actually got better. Right
now all I'm certain of is that 3.13 is bad and 3.15-rc3 is good. If we
could narrow that down to one -rc being bad and the next one being good,
or 3.14 being bad and 3.15-rc1 being good. Then I could look for commits
which might be related, or worst case run a bisect between those two to
find what actually solved your problem, so we can hopefully backport the
fix to 3.13.

It's probably also a good idea to test 3.15-rc3 or later with the -8 and
-9 firmware to see if that was responsible. Unfortunately that's an
awful lot to test, espeically for a problem that takes a while to show
up. Hopefully the wifi-debug data will give a better idea where to look.
In the mean time I'll look at the syslog you attached and see what I can
learn.

[Ethan Blanton (eblanton)]

Seth, I just sent some wifi-debug output to your @canonical email address.

This may not be a great capture, let me know if it's not useful to you and I'll try to get another. I have unfortunately not been sitting at this laptop much the past couple of days for various reasons, so when I've started captures they've run into the GB+ range without me being certain that they contained anything useful. This capture was started *during* an intermittent connection period, although it is acting more like simply a poor signal than the frequent association loss that I sometimes experience. The location where I am does not get great signal strength, but with a good driver+firmware it is a reliable connection and does not stutter like it was when I took the capture.

Let me know if it's helpful, not helpful, requires follow-up, etc.

[Seth Forshee (sforshee)]

I can see the driver trying to scale down the rate because of too many transmit failures, but it looks like it's already at the lowest rate. The signal levels the driver reports look fairly low but not unreasonable (around -80 to -85 dBm). My experience with older Intel wireless hardware was that it didn't do as well with weak signals as most other hardware, but I haven't checked with their newer hardware. There's also nothing recorded about the noise level, which could also be a contributing factor.

However, right now I don't see anything the driver is doing to contribute to this problem. I'll look at the data some more, but I think it would be a good idea to try and get a trace which shows the disconnections as well.

[Davide (dspinell)]

In my case (Ubuntu 14.04 on dell xps13 "Sputnik", kernel 3.13) the wifi performance substantially degraded after the recent linux-firmware update.

[Seth Forshee (sforshee)]

Ethan: I've been looking at your dump more. What seems to be happening is that you're getting a reliable connection at CCK rates (low number of tx retries), then the rate control algorithm bumps you up to HT rates and you start getting a high number of retries. After a while you get bumped back down to CCK rates, and the tx retry count goes down again.

I honestly don't know much about the rate control algorithm, but from what I do know this behavior seems approximately right - push the rate up until you start having problems, then push it back a notch. If your connection feels flaky though then maybe it isn't being aggressive enough on the backoff or something like that.

None of this should really have any bearing on the beacon loss issue however.

[Seth Forshee (sforshee)]

Davide: You should open a new bug for your issue by running 'ubuntu-bug linux' in a terminal. Thanks!

[Seth Forshee (sforshee)]

Ethan: I built a test kernel with a single backport from 3.14 which is supposed to alleviate beacon loss problems somewhat. This won't help with any stutter in the connection, but it might help with the disconnects. Let me know if it helps. Thanks!

http://people.canonical.com/~sforshee/lp1349572/linux-3.13.0-32.57+lp1349572/

[eric (emagar)]

Same problem with 12.04 -> 14.04 upgrade on 8/7/2014. An earlier incarnation of Ubuntu (Oneiric?) had similar issue, I seem to remember.

[penalvch (penalvch)]

eric, thank you for your comment. Unfortunately, this bug report is not scoped to you, or your problem. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into the default Ubuntu kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Seth Forshee (sforshee)]

Ethan: I found another fix from 3.15 which is related to the recovery from beacon loss events for drivers like iwlwifi. I posted a build here (which includes the backport from comment #58 as well):

  http://people.canonical.com/~sforshee/lp1349572/linux-3.13.0-32.57+lp1349572v201408111147/

Please try it out and let me know if it helps. Thanks!

[Ethan Blanton (eblanton)]

I am now running 3.13.0-32-generic #57+lp1349572v201408111147, I will let you know how it goes. I have been having relatively less trouble than usual the past few days (for whatever reason; this bug is rather inconsistent), so it may take a while to know if there's much improvement.

Thanks for all of your effort on this bug.

[Ethan Blanton (eblanton)]

After a week on 3.13.0-32-generic #57+lp1349572v201408111147 on several wireless networks, I believe I can confidently say that the disassociation problem is not present in this kernel. I still get dragging speeds from time to time consistent with the rate-related problems discussed previously, but I do not lose association. In general the experience is much improved. (I've not had to reboot the machine or reload the wireless drivers at all, for example!)

I'm not sure where that puts us with regards to "fixing" this bug, or if there's anything else you'd still like to see (different kernel versions, specific debug dumps, etc.). Please let me know if there is.

[Seth Forshee (sforshee)]

Thanks for the testing. We've already committed those changes based on feedback from bug 1349572, so we can leave this bug open and continue trying to find a fix for the poor performance.

FYI, I'm travelling this week so I probably won't be able to do much more work on this until next week.

[Ethan Blanton (eblanton)]

I was just unable to connect using 3.13.0-32-generic #57+lp1349572v201408111147, and the problem was fixed by removing and reinserting iwlmvm and iwlwifi. Due to an unfortunate stupidity on my part, I am unable to send the wifi-debug files.

This problem occurred, I believe, due to spending a long duration of time where the wifi signal was very poor. I may be able to reproduce, I will try this evening.

In the meantime, what kernel should I be running? Should I revert to the distribution kernel, is it patched?

[Seth Forshee (sforshee)]

The distro kernel isn't patched yet as stable release update kernels go through a fairly lengthy (but necessary) regression testing cycle before they are released. I'd estimate that at this point we're probably 4 or 5 weeks away from having a kernel with those patches pushed out to the distro at large. Until then you can continue running that test build if you like.

[Antonio Cañas Vargas (acanas)]

Apparently the problem has been solved in my XPS 13 with Ubuntu 14.04 using the instructions from http://ubuntuforums.org/showthread.php?t=2012228&p=12061341#post12061341

[penalvch (penalvch)]

Antonio Cañas Vargas, as far as Ubuntu is concerned, WORKAROUNDs, hacks, etc. does not solve a bug as outlined in https://wiki.ubuntu.com/Bugs/Status . So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into the default Ubuntu kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

As well, please do not announce in this report you created a new bug report.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Seth Forshee (sforshee)]

Ethan: I got a new patch from Intel from Intel for 7260 wireless problems. Can you try out the build below and see if it helps? Thanks!

http://people.canonical.com/~sforshee/iwl-ltr/trusty/

[Ethan Blanton (eblanton)]

I have just rebooted to this kernel, I will report back with any improvements or regressions after some experience using it.

[Removed by request (removed4589840)]

I'm still experiencing issues. Every now and then my network becomes really, really slow. A continuous ping to my router shows high latency and packet loss during these episodes. The problem resolves after about 3-5 mins if left unattended, or instantly if I disable/enable wifi.?field.comment=I'm still experiencing issues. Every now and then my network becomes really, really slow. A continuous ping to my router shows high latency and packet loss during these episodes. The problem resolves for about 30-60 mins if I disable/enable wifi, until it reappears. Iwconfig shows link quality going back and forth from 60-70 to 8-13 (without moving my device an inch of course.) When the device is working well the link quality stays between 60-70.

$ uname -rv
3.13.0-37-generic #64+iwlltr0001 SMP Tue Sep 30 18:52:17 UTC 2014

[Ethan Blanton (eblanton)]

Seth,

It's not completely clear to me whether this kernel helps or not, but I think it does. Certainly it is no worse than the last kernel I tested.

* It is my general sense that I am experiencing fewer slowdowns, but they are certainly still occurring.

 * I have had zero complete failures of the driver requiring a removal/reinstall, but those do not happen reliably so I cannot say whether it is due to the new driver or whether I have simply been lucky.

 * With the previous kernel I had numerous 5-seconds-on/5-seconds-off usability problems where the driver was bouncing between a usable rate and an unusable rate very consistently until the machine was moved or the driver reloaded; I have not experienced that at all with this kernel, but again, it is an intermittent issue so that is not conclusive.

I can take some wireless debug logs if you like, but without major noticeable events to correlate them to, I am not sure how helpful they will be. There's still a fair amount of noise in the syslog about various states changing and things going on, but often they do not correspond to any perceivable behaviors.

Ethan

[Ethan Blanton (eblanton)]

Still using 3.13.0-37-generic #64+iwlltr0001, this afternoon I had a spat where the card lost association and would not reacquire it. Removing and reinserting iwlwifi/iwlmvm fixed it immediately. Seth, I am emailing you wifi-debug output from both before and after reinsertion (which should show both the failure and the fix).

[Seth Forshee (sforshee)]

On Fri, Nov 14, 2014 at 02:43:56PM -0000, Christopher M. Penalver wrote:
> Ethan Blanton, could you please post any debug attachments uncompressed
> and untarred to this report (not e-mailed to one person) so others may
> review?

Christopher: These dumps may contain private data, possibly including
unencrypted network traffic. Please don't request that people attach
such data to public bug reports.

[penalvch (penalvch)]

Seth Forshee / Eathan Blanton, my apologies for this erroneous request. The comment has been hidden, so please disregard.

[gianluca (antonelli1970)]

hello,

same issue for me, intermittent access, poor bandwidth, no connection at all with some access points. please let me know how i can be of help (please give me very clear instructions...)

best,
g.

Dell XPS13 with Ubuntu 14.04

$ uname -a
Linux drogo 3.13.0-39-generic #66-Ubuntu SMP Tue Oct 28 13:30:27 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux

$ lshw
...
           *-network
                description: Wireless interface
                product: Wireless 7260
                vendor: Intel Corporation
                physical id: 0
                bus info: pci@0000:02:00.0
                logical name: wlan0
                version: 6b
                serial: e8:b1:fc:41:49:e3
                width: 64 bits
                clock: 33MHz
                capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
                configuration: broadcast=yes driver=iwlwifi driverversion=3.13.0-39-generic firmware=22.24.8.0 ip=192.168.1.132 latency=0 link=yes multicast=yes wireless=IEEE 802.11abgn
                resources: irq:59 memory:f0400000-f0401fff
...

[Davide (dspinell)]

For me then problem solved after upgrading to 14.10

On 13:05, Sat, Nov 15, 2014 gianluca <email address hidden> wrote:

> hello,
>
> same issue for me, intermittent access, poor bandwidth, no connection
> at all with some access points. please let me know how i can be of help
> (please give me very clear instructions...)
>
> best,
> g.
>
> Dell XPS13 with Ubuntu 14.04
>
> $ uname -a
> Linux drogo 3.13.0-39-generic #66-Ubuntu SMP Tue Oct 28 13:30:27 UTC 2014
> x86_64 x86_64 x86_64 GNU/Linux
>
> $ lshw
> ...
> *-network
> description: Wireless interface
> product: Wireless 7260
> vendor: Intel Corporation
> physical id: 0
> bus info: pci@0000:02:00.0
> logical name: wlan0
> version: 6b
> serial: e8:b1:fc:41:49:e3
> width: 64 bits
> clock: 33MHz
> capabilities: pm msi pciexpress bus_master cap_list
> ethernet physical wireless
> configuration: broadcast=yes driver=iwlwifi
> driverversion=3.13.0-39-generic firmware=22.24.8.0 ip=192.168.1.132
> latency=0 link=yes multicast=yes wireless=IEEE 802.11abgn
> resources: irq:59 memory:f0400000-f0401fff
> ...
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1315221
>
> Title:
> 8086:08b1 (rev 6b) [Dell XPS 13 9333] iwlwifi regularly loses
> connection/becomes unusable on Intel 7260
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/
> 1315221/+subscriptions
>

[gianluca (antonelli1970)]

HI,

this is indeed interesting.

Was it an official workaround? I would like to stay on 14.04 (since it is LTS), does this patch will be released in one of next updates?

The wifi issue is really huge for me, it does not even connect with EDUROAM (the international educational wifi network) and since it is a laptop without ethernet cable I should fix this issue before next working travel...

Best,
g.

[eno (enoquick)]

Thank to all,I had the same problem
With the update to kernel 3.15.10-031510 the problem is solved

[penalvch (penalvch)]

eno, thank you for your comment. So your hardware and problem may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into the default Ubuntu kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
https://wiki.ubuntu.com/Kernel/Policies/DuplicateBugs
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

As well, please do not announce in this report you created a new bug report.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[gianluca (antonelli1970)]

hello,

sorry for the basic question...

during the last update the application "Software Updater" reported me a wrong package installation. the package is related to the wifi-bluetooth of the intel chipset we are talking about in this discussion. however, i'm not able to find any more the log concerning that package. Running the software does not provide any usefull information but simply reporting what shown in the snapshot attached.

where can i find it?

thank
g.

[Shih-Yuan Lee (fourdollars)]

@gianluca,

It seems that you are using a preloaded Ubuntu system.
What is your hardware vendor and preloaded Ubuntu series?
Did you ever upgrade the system from Ubuntu 12.04 to Ubuntu 14.04?

[gianluca (antonelli1970)]

hello fourdollars,

thanks for the reply.

The machine is a Dell XPS. I bought it with ubuntu 12.04 on it and the very first operation I did has been an update to 14.04

To be honest, I do not remember if the problem arose also with the 12.04 version.

g.

[Shih-Yuan Lee (fourdollars)]

@gianluca,

Could you also provide the list of `dkms status`?

[gianluca (antonelli1970)]

here we are:

oem-audio-hda-daily-lts-quantal, 0.201308192259~precise1, 3.5.0-56-generic, x86_64: installed
oem-wireless-bluetooth-intel-7260, 3.10.20130828, 3.5.0-56-generic, x86_64: installed
virtualbox, 4.3.10, 3.13.0-39-generic, x86_64: installed
virtualbox, 4.3.10, 3.13.0-40-generic, x86_64: installed
virtualbox, 4.3.10, 3.13.0-43-generic, x86_64: installed
virtualbox, 4.3.10, 3.5.0-56-generic, x86_64: installed

best,
g.

[Shih-Yuan Lee (fourdollars)]

@gianluca,

If you are using the Linux kernel from Ubuntu 14.04, such as 3.13.0-{39,40,43}-generic, those DKMS packages should not affect your system.
You can remove them by `sudo apt-get purge oem-audio-hda-daily-lts-quantal oem-wireless-bluetooth-intel-7260` if you think they are redundant.
`uname -r` can check the kernel version.

BTW, `ubuntu-drivers devices` may also provide the helpful information.

[gianluca (antonelli1970)]

@fourdollars

i removed those packages and, as you anticipated, the problem still is there.

thanks for your help, waiting (impatiently), the issue to evolve...

best,
g.

[penalvch (penalvch)]

Seth Forshee, Ethan Blanton has provided the requested information as per https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1315221/comments/75 . Given you are the only one with access to the requested logs, what would you like to have done now?

[sticks (orawas)]

Just FYI, there is an updated bios for this hardware (A06) posted on December 22 2014. I don't believe it would influence this bug though. The fixes, as listed here: http://www.dell.com/support/home/us/en/04/Drivers/DriversDetails?driverId=TDWHX

"Fixes
- Add code to prevent incorrect characters (2/4/6/8) appear if slide direction key quickly.

Enhancements
- Not Applicable. "

Hoping these wifi issues get addressed soon in the LTS kernel as I am also affected on the same hardware (Dell XPS 13 9333).

[penalvch (penalvch)]

sticks, what impact a BIOS update for Ubuntu may have is typically not captured in vendor release notes as outlined in https://help.ubuntu.com/community/ReportingBugs#Hardware_bug_reports_.28linux_kernel.2C_xorg.2C_sound.2C_etc..29 .

However, so your problem and hardware may be tracked, could you please file a new report with Ubuntu by executing the following in a terminal while booted into the default Ubuntu kernel (not a mainline one) via:
ubuntu-bug linux

For more on this, please read the official Ubuntu documentation:
Ubuntu Bug Control and Ubuntu Bug Squad: https://wiki.ubuntu.com/Bugs/BestPractices#X.2BAC8-Reporting.Focus_on_One_Issue
Ubuntu Kernel Team: https://wiki.ubuntu.com/KernelTeam/KernelTeamBugPolicies#Filing_Kernel_Bug_reports
https://wiki.ubuntu.com/Kernel/Policies/DuplicateBugs
Ubuntu Community: https://help.ubuntu.com/community/ReportingBugs#Bug_reporting_etiquette

When opening up the new report, please feel free to subscribe me to it.

As well, please do not announce in this report you created a new bug report.

Thank you for your understanding.

Helpful bug reporting tips:
https://wiki.ubuntu.com/ReportingBugs

[Ethan Blanton (eblanton)]

I am now running BIOS A06 and Ubuntu 14.10 due to a mainboard failure on the laptop necessitating repair by Dell. I will update here if there appear to be any substantial improvements/regressions. I apologize if this loses track of the state for LTS, but as this is a machine I need for daily use I thought it best to take advantage of the enforced reinstall to update to 14.10.

[Ethan Blanton (eblanton)]

A06
11/07/2014

[Pavel (pavel-sa)]

ApportVersion: 2.14.1-0ubuntu3.6
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC1: isvoboda 2158 F.... pulseaudio
 /dev/snd/controlC0: isvoboda 2158 F.... pulseaudio
 /dev/snd/pcmC0D0p: isvoboda 2158 F...m pulseaudio
CurrentDesktop: XFCE
DistroRelease: Ubuntu 14.04
InstallationDate: Installed on 2014-09-30 (108 days ago)
InstallationMedia: Xubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140723)
MachineType: MSI MS-7851
NonfreeKernelModules: nvidia
Package: linux (not installed)
ProcFB: 0 EFI VGA
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.13.0-40-generic.efi.signed root=UUID=b6e4afa1-c663-4dd8-98fc-69d94dcae276 ro quiet splash vt.handoff=7
ProcVersionSignature: Ubuntu 3.13.0-40.69-generic 3.13.11.10
RelatedPackageVersions:
 linux-restricted-modules-3.13.0-40-generic N/A
 linux-backports-modules-3.13.0-40-generic N/A
 linux-firmware 1.127.11
Tags: trusty
Uname: Linux 3.13.0-40-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 11/21/2014
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: V5.5
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: H97I AC (MS-7851)
dmi.board.vendor: MSI
dmi.board.version: 1.0
dmi.chassis.asset.tag: To be filled by O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: MSI
dmi.chassis.version: 1.0
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrV5.5:bd11/21/2014:svnMSI:pnMS-7851:pvr1.0:rvnMSI:rnH97IAC(MS-7851):rvr1.0:cvnMSI:ct3:cvr1.0:
dmi.product.name: MS-7851
dmi.product.version: 1.0
dmi.sys.vendor: MSI

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

apport information

[Pavel (pavel-sa)]

Hi I am runing Xubuntu 14.04.1 with the same wifi card (ntel® Dual Band Wireless-AC 7260). I have the latest bios. The problem with the unstable wifi connection (wpa2, 2.4GHz) appears in kernels > 3.0.13-40. ie 3.0.13.40 works well while the actual 13.0.13.44 suffers with the connection problem.
In my case I am running the desktop with the msi H97I AC motherboard.

[penalvch (penalvch)]

Pavel, it would be most helpful if you filed a new report (not apport-collect to another report) via a terminal:
ubuntu-bug linux

[Pavel (pavel-sa)]

Sure, sorry for the mess.

[Ethan Blanton (eblanton)]

OK. 3.16.0-29 seems to be much better, but I just experienced the same symptoms as for the logs (I believe) referred to in comment 77 above; specifically, the machine lost association with the AP and could not reestablish. Removing and reinserting the iwlmvm and iwlwifi modules fixed the problem and I was able to reassociate (using Network Manager) immediately.

Seth, I took a wifi-debug dump during the period when it would not reassociate, let me know if you want it.

[gianluca (antonelli1970)]

Hello,

I filled an apport bug in another topic: #1426259

imho this should linked with this one but i'm not sure on how to proceed.

i'm sorry to bother with chat-like questions, if this is not the correct place just let me know:

- is this bug affecting all distro? i'm often abroad and a laptop without wifi is quite limiting...

- in case no, anyone that already tested a working one?

- in case i will wait for the bug to be solved is there any schedule?

thanks a lot for any reply,
g.

[gianluca (antonelli1970)]

Hello,

I solved the problem. Actually, I do not know how so, in order to be useful to someone, I share the operations made:

- I updated the BIOS of my Dell XPS 13 from A05 to A06 as suggested in #1426259. The following weeks I then verified that it worked "most of the times". I traveled and, let me say that it worked with 8 different networks on 10;

- For another reason (noise from the audio system), Dell changed my motherboard.

Since then, the wifi works regularly but the BIOS is the previous one, A05.

Best,
g.

[Ethan Blanton (eblanton)]

I'm now on 15.04, BIOS A06, kernel 3.19.0-25, and I still have intermittent problems, although things are better than they were at their worst. When I do have problems, removing and reinserting iwlmvm/iwlwifi fixes it.

[Ethan Blanton (eblanton)]

15.10 and 16.04 both appear to be much improved. I haven't been running 16.04 long enough to be sure, but 15.10 probably required reinsertion of the drivers no more than 2-3 times over the six months I ran it.

What I do find is that the wireless card is often (but not always) disabled after wake from sleep regardless of its state prior to sleep. This is of minimal consequence as it is easily remedied by right-clicking on nm-applet.

[Ethan Blanton (eblanton)]

This just happened again, linux-image-4.4.0-31-generic 4.4.0-31.50, 16.04. It certainly happens less often with 16.04 than it did in 15.04 and previous.

[Ethan Blanton (eblanton)]

Yes, I am running A06. However, a) the A08 update does not indicate anything but a touchpad fix for Windows 10 32-bit (I realize this can be unreliable) and b) since the A06 update I have been unable to successfully boot a FreeDOS image to update my BIOS.

If you have any information on how to successfully update to A08 without an installed Windows OS, I'd be happy to hear it.

[Ethan Blanton (eblanton)]

This problem went away some time between 16.04 and 19.10 (I went from 16.04 to 18.04 some time ago, and I believe it disappeared in that jump); I no longer have a way to test it on 16.04.