iwlagn creates cpu hog

[Khem Raj]

Binary package hint: linux-backports-modules-2.6.31-3-generic

I have seen a cpu usage of 100% by iwlagn on my IBM T61 using karmic alpha 3 (kubuntu)
The workaround was

sudo modprobe -r iwlagn

sudo modprobe iwlagn

and then hog was gone and also wireless worked well

uname tells me this

2.6.31-4-generic #22-Ubuntu SMP Fri Jul 24 18:05:56 UTC 2009 x86_64 GNU/Linux

[Ross Patterson (rossp)]

I've been seeing this as well ever since I upgraded to karmic, starting with a 2.6.30 kenel

[Mike Butash (michael-butash)]

I just started getting this behaviour a day or so after upgrading to karmic where I'm having to rmmod and modprobe the iwlagn driver. It appears there is a patch for the driver source, can you review and look at updating the iwlagn module in the karmic kernel?

http://bugzilla.intellinuxwireless.org/show_bug.cgi?id=1934

Thanks!

[Pär Lindfors (paran)]

This bug is reported against backports-modules, but I don't see
anything in the comments that suggest that the reporters actually use
this.

So to clarify, do you have the package linux-backports-modules-karmic
installed when you see this problem?

[Muelli (ubuntu-bugs-auftrags-killer)]

muelli@xbox:~$ apt-cache policy linux-backports-modules-karmic
linux-backports-modules-karmic:
  Installed: (none)
  Candidate: 2.6.31.14.27
  Version table:
     2.6.31.14.27 0
        400 http://de.archive.ubuntu.com karmic/main Packages
muelli@xbox:~$

And I see this very annoying problem very often.
I totally willing to extensively debug this, but I need instructions.

[Muelli (ubuntu-bugs-auftrags-killer)]

btw, Thinkpad x61s, and I get a buttload of these in my dmesg:
[163641.442758] iwlagn 0000:03:00.0: Can not allocate SKB buffers
[163641.464284] swapper: page allocation failure. order:2, mode:0x4020
[163641.464289] Pid: 0, comm: swapper Tainted: G WC 2.6.31-14-generic #48-Ubuntu
[163641.464292] Call Trace:
[163641.464294] <IRQ> [<ffffffff810e083c>] __alloc_pages_slowpath+0x4cc/0x4e0
[163641.464308] [<ffffffff810e099e>] __alloc_pages_nodemask+0x14e/0x150
[163641.464313] [<ffffffff81111dfa>] kmalloc_large_node+0x5a/0xb0
[163641.464317] [<ffffffff81115fa5>] __kmalloc_node_track_caller+0x135/0x180
[163641.464332] [<ffffffffa021c899>] ? iwl_rx_allocate+0x1a9/0x230 [iwlcore]
[163641.464338] [<ffffffff8142cee8>] ? skb_queue_tail+0x48/0x60
[163641.464343] [<ffffffff8142e41b>] __alloc_skb+0x7b/0x180
[163641.464353] [<ffffffffa021c899>] iwl_rx_allocate+0x1a9/0x230 [iwlcore]
[163641.464364] [<ffffffffa021c466>] ? iwl_rx_reply_rx+0x1f6/0x2e0 [iwlcore]
[163641.464375] [<ffffffffa021dc36>] iwl_rx_replenish_now+0x16/0x30 [iwlcore]
[163641.464384] [<ffffffffa023a4ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[163641.464392] [<ffffffffa023a767>] iwl_irq_tasklet_legacy+0x207/0x440 [iwlagn]
[163641.464398] [<ffffffff81063ee0>] tasklet_action+0xd0/0xe0
[163641.464402] [<ffffffff8106549d>] __do_softirq+0xbd/0x200
[163641.464407] [<ffffffff810131ec>] call_softirq+0x1c/0x30
[163641.464411] [<ffffffff81014bc5>] do_softirq+0x55/0x90
[163641.464415] [<ffffffff81065205>] irq_exit+0x85/0x90
[163641.464418] [<ffffffff81014100>] do_IRQ+0x70/0xe0
[163641.464423] [<ffffffff81012a13>] ret_from_intr+0x0/0x11
[163641.464425] <EOI> [<ffffffff812d7ed9>] ? acpi_idle_enter_bm+0x28b/0x2bf
[163641.464434] [<ffffffff812d7ed2>] ? acpi_idle_enter_bm+0x284/0x2bf
[163641.464439] [<ffffffff813fe40b>] ? cpuidle_idle_call+0x9b/0xf0
[163641.464443] [<ffffffff81010e12>] ? cpu_idle+0xb2/0x100
[163641.464448] [<ffffffff815239f6>] ? start_secondary+0xa9/0xab
[163641.464450] Mem-Info:
[163641.464452] Node 0 DMA per-cpu:
[163641.464456] CPU 0: hi: 0, btch: 1 usd: 0
[163641.464459] CPU 1: hi: 0, btch: 1 usd: 0
[163641.464461] Node 0 DMA32 per-cpu:
[163641.464464] CPU 0: hi: 186, btch: 31 usd: 98
[163641.464467] CPU 1: hi: 186, btch: 31 usd: 180
[163641.464472] Active_anon:275814 active_file:16352 inactive_anon:146177
[163641.464474] inactive_file:16173 unevictable:5 dirty:305 writeback:164 unstable:0
[163641.464475] free:3407 slab:20027 mapped:15135 pagetables:7640 bounce:0
[163641.464478] Node 0 DMA free:7876kB min:40kB low:48kB high:60kB active_anon:1652kB inactive_anon:2828kB active_file:1696kB inactive_file:1132kB unevictable:0kB present:15332kB pages_scanned:0 all_unreclaimable? no
[163641.464485] lowmem_reserve[]: 0 1963 1963 1963
[163641.464491] Node 0 DMA32 free:5752kB min:5648kB low:7060kB high:8472kB active_anon:1101604kB inactive_anon:581880kB active_file:63712kB inactive_file:63560kB unevictable:20kB present:2010592kB pages_scanned:32 all_unreclaimable? no
[163641.464499] lowmem_reserve[]: 0 0 0 0
[163641.464503] Node 0 DMA: 35*4kB 31*8kB 16*16kB 2*32kB 8*64kB 4*128kB 4*256kB 2*512kB 2*1024kB 1*2048kB 0*4096kB = 7876kB
[163641...

[Muelli (ubuntu-bugs-auftrags-killer)]

Architecture: amd64
DistroRelease: Ubuntu 9.04
Package: linux 2.6.31.14.27
PackageArchitecture: amd64
Uname: Linux 2.6.31-14-generic x86_64
UserGroups: adm admin audio cdrom dialout dip floppy fuse kvm libvirtd lpadmin netdev plugdev powerdev scanner tty vboxusers video

[Muelli (ubuntu-bugs-auftrags-killer)]

https://bugzilla.redhat.com/show_bug.cgi?id=529536 and http://bugzilla.kernel.org/show_bug.cgi?id=14141 for relevant bugreports. According to the latter, upstream has fixed this (but not backported?), bug I can't see in which revision.

[Muelli (ubuntu-bugs-auftrags-killer)]

With the backport-modules, I feel it's harder to trigger but when it hits, it seems to be worse:

[200790.561493] Free swap = 971420kB
[200790.561493] Total swap = 1959920kB
[200790.561493] 513712 pages RAM
[200790.561493] 9742 pages reserved
[200790.561493] 57599 pages shared
[200790.561493] 476022 pages non-shared
[200790.582266] kcryptd_io: page allocation failure. order:2, mode:0x4020
[200790.582275] Pid: 858, comm: kcryptd_io Tainted: G WC 2.6.31-14-generic #48-Ubuntu
[200790.582281] Call Trace:
[200790.582285] <IRQ> [<ffffffff810e083c>] __alloc_pages_slowpath+0x4cc/0x4e0
[200790.582309] [<ffffffff810e099e>] __alloc_pages_nodemask+0x14e/0x150
[200790.582320] [<ffffffff81111dfa>] kmalloc_large_node+0x5a/0xb0
[200790.582328] [<ffffffff81115fa5>] __kmalloc_node_track_caller+0x135/0x180
[200790.582360] [<ffffffffa0510967>] ? iwl_rx_allocate+0x197/0x2f0 [iwlcore]
[200790.582372] [<ffffffff8142e41b>] __alloc_skb+0x7b/0x180
[200790.582393] [<ffffffffa0510967>] iwl_rx_allocate+0x197/0x2f0 [iwlcore]
[200790.582416] [<ffffffffa0511dd6>] iwl_rx_replenish_now+0x16/0x30 [iwlcore]
[200790.582433] [<ffffffffa0462eda>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[200790.582449] [<ffffffffa0463308>] iwl_irq_tasklet_legacy+0x1d8/0x4a0 [iwlagn]
[200790.582460] [<ffffffff81063ee0>] tasklet_action+0xd0/0xe0
[200790.582469] [<ffffffff8106549d>] __do_softirq+0xbd/0x200
[200790.582478] [<ffffffff810131ec>] call_softirq+0x1c/0x30
[200790.582485] [<ffffffff81014bc5>] do_softirq+0x55/0x90
[200790.582493] [<ffffffff81065205>] irq_exit+0x85/0x90
[200790.582500] [<ffffffff81014100>] do_IRQ+0x70/0xe0
[200790.582509] [<ffffffff81012a13>] ret_from_intr+0x0/0x11
[200790.582514] <EOI> [<ffffffff81261f3c>] ? get_request+0x1fc/0x370
[200790.582529] [<ffffffff812620d5>] ? get_request_wait+0x25/0x1a0
[200790.582538] [<ffffffff81256fdb>] ? elv_merge+0x1cb/0x200
[200790.582545] [<ffffffff812622e3>] ? __make_request+0x93/0x440
[200790.582556] [<ffffffff81260e03>] ? generic_make_request+0x1a3/0x4d0
[200790.582564] [<ffffffff8105225b>] ? dequeue_entity+0x1b/0x240
[200790.582574] [<ffffffff8114a006>] ? bio_alloc_bioset+0x56/0xf0
[200790.582602] [<ffffffffa0046938>] ? kcryptd_io_read+0xd8/0x110 [dm_crypt]
[200790.582615] [<ffffffffa0046970>] ? kcryptd_io+0x0/0x30 [dm_crypt]
[200790.582628] [<ffffffffa0046998>] ? kcryptd_io+0x28/0x30 [dm_crypt]
[200790.582638] [<ffffffff810737a5>] ? run_workqueue+0x95/0x170
[200790.582647] [<ffffffff81073924>] ? worker_thread+0xa4/0x120
[200790.582656] [<ffffffff81078b30>] ? autoremove_wake_function+0x0/0x40
[200790.582665] [<ffffffff81073880>] ? worker_thread+0x0/0x120
[200790.582672] [<ffffffff81078746>] ? kthread+0xa6/0xb0
[200790.582680] [<ffffffff810130ea>] ? child_rip+0xa/0x20
[200790.582689] [<ffffffff810786a0>] ? kthread+0x0/0xb0
[200790.582696] [<ffffffff810130e0>] ? child_rip+0x0/0x20
[200790.582701] Mem-Info:
[200790.582704] Node 0 DMA per-cpu:
[200790.582712] CPU 0: hi: 0, btch: 1 usd: 0
[200790.582718] CPU 1: hi: 0, btch: 1 usd: 0
[200790.582722] Node 0 DMA32 per-cpu:
[200790.582729] CPU 0: hi: 186, btch: 31 usd: 54
[200790.582734] CPU 1: hi: 186, btch: 31 usd: 62
[20079...

[Emilio (turl)]

I can reproduce this bug too. I am running Ubuntu Karmic without the backport modules. I have just installed them too.

My WiFi card is:
07:00.0 Network controller: Intel Corporation Wireless WiFi Link 5100

I attach my /var/log/messages so you can see the errors it generates. I didn't use dmesg because it was polluted with CPU downclocking messages because of the driver using 100% of the CPU and overheating it :)

[Emilio (turl)]

Also, I'm using a WPA WiFi G connection if that matters.

[Thierry LARMIER (thierry-larmier)]

Same problem: 100% CPU usage by iwlagn

kernel : 2.6.31-14-generic
Ubuntu 9.10 - le Koala Karmique

lspci:
------------------------------------------------------------
00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory Controller Hub (rev 03)
00:02.0 VGA compatible controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03)
00:02.1 Display controller: Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller (rev 03)
00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #4 (rev 03)
00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #5 (rev 03)
00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #2 (rev 03)
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 03)
00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 1 (rev 03)
00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 2 (rev 03)
00:1c.2 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 3 (rev 03)
00:1c.3 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 4 (rev 03)
00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 5 (rev 03)
00:1c.5 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express Port 6 (rev 03)
00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #1 (rev 03)
00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #2 (rev 03)
00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB UHCI Controller #3 (rev 03)
00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 EHCI Controller #1 (rev 03)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)
00:1f.0 ISA bridge: Intel Corporation 82801HEM (ICH8M) LPC Interface Controller (rev 03)
00:1f.2 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) SATA IDE Controller (rev 03)
00:1f.3 SMBus: Intel Corporation 82801H (ICH8 Family) SMBus Controller (rev 03)
02:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or AGN [Kedron] Network Connection (rev 61)
08:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 01)
0c:07.0 FLASH memory: ENE Technology Inc ENE PCI Memory Stick Card Reader Controller
0c:07.1 SD Host controller: ENE Technology Inc ENE PCI SmartMedia / xD Card Reader Controller
0c:07.3 FLASH memory: ENE Technology Inc ENE PCI Secure Digital / MMC Card Reader Controller
0c:09.0 FireWire (IEEE 1394): VIA Technologies, Inc. VT6306 Fire II IEEE 1394 OHCI Link Layer Controller (rev c0)
--------------------------------------

dmesg | grep iwlagn
----------------------------------
    5.921172] iwlagn: Intel(R) Wireless WiFi Link AGN driver for Linux, 1.3.27k
[ 5.921175] iwlagn: Copyright(c) 2003-2009 Intel Corporation
[ 5.921254] iwlagn 0000:02:00.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16
[ 5.921263] iwlagn 0000:02:00.0: setting latency timer to 64
[ 5.921286] iwlagn 0000:02:00.0: Detected Intel Wireless WiFi Link 4965AGN REV=0x4
[ 5.965405...

[cuc (cuc+)]

same here with:

08:00.0 Network controller: Intel Corporation PRO/Wireless 5300 AGN [Shiloh] Network Connection

using N-mode

isn't really easy to reproduce... this just happens some now and thens (1-2times a month) - can occur on high network loads and also on nearly idle networking..

uname -r: 2.6.31-16-generic also was there with -14 and -15

see attachment for call traces in dmesg

[Bèr Kessels (berkes) (ber)]

I can reproduce this quite often on high MySQL and/or Apache load.
Not always, but if I get a hogging iwlagn, it most often is due to heavy load on my local mysqld and apache.
To me, this hints towards either heavy load on the localhost/loopback network, or towards processes with higher (?) priority breaking iwlagn.

Hope this helps.

[jmrk (joergen-kornfeld)]

Affects me too, on HP EliteBook 8530w. Had heavy wifi load over Network-Manager VPN while going through a large remote logfile with VIM.

[radioboy (the-radioboy)]

Same problem here, on a Dell 1535 notebook, with Linux Mint 8 (x64) using Ubuntu backports repository.
The wireless device is Intel Wireless WiFi link 5100.

Right now I'm using cable connection to internet, and top reports iwlagn being active for 1009 minutes. Uptime is 1698 minutes.
CPU 99-100%, memory 0.0%. It's only using one of the dual core processors.
The hog started no more than a 10-15 minutes ago, as far as I can tell.

$ dmesg |grep iwlagn
[40592.432763] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40611.061646] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40611.061662] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40611.071228] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40611.071228] [<ffffffffa05064f8>] iwl_rx_handle+0x288/0x2f0 [iwlagn]
[40611.071228] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40611.071228] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40612.234893] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40612.234909] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40612.244510] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40612.244510] [<ffffffffa05064f8>] iwl_rx_handle+0x288/0x2f0 [iwlagn]
[40612.244510] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40612.244510] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40613.210416] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40613.210432] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40613.213449] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40613.213449] [<ffffffffa05064f8>] iwl_rx_handle+0x288/0x2f0 [iwlagn]
[40613.213449] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40613.213449] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40614.543052] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40614.543060] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40614.552836] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40614.552836] [<ffffffffa05064f8>] iwl_rx_handle+0x288/0x2f0 [iwlagn]
[40614.552836] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40614.552836] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40615.565580] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40615.565596] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40615.572506] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40615.572506] [<ffffffffa05064f8>] iwl_rx_handle+0x288/0x2f0 [iwlagn]
[40615.572506] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40615.572506] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40616.386429] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40616.386445] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40616.394946] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40616.394946] [<ffffffffa05064f8>] iwl_rx_handle+0x288/0x2f0 [iwlagn]
[40616.394946] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[40616.394946] iwlagn 0000:04:00.0: Can not allocate SKB buffers
[40618.686255] [<ffffffffa05064ba>] iwl_rx_handle+0x24a/0x2f0 [iwlagn]
[40618.686271] [<ffffffffa0506ad8>] iwl_irq_tasklet+0x138/0x480 [iwlagn]
[...

[Miguel (muchochini)]

This happened to me today, 100% CPU usage.

I have an intel 5300 AGN, running 2.6.31-18 Ubuntu Karmic 9.10 amd64. It happens to me rarely and I don't know how to reproduce it.

[MMS-Prodeia (mms-prodeia)]

03:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or AGN [Kedron] Network Connection (rev 61)

Linux thinkpad 2.6.31-18-generic #55-Ubuntu SMP Fri Jan 8 14:54:52 UTC 2010 x86_64 GNU/Linux

I agree to this bug!
There are several ways to make the iwlagn module crash:

* put the wireless under high load (file copy in local network)
* use USB (maybe use usb-creator) while beeing online with iwlagn.

I tried using linux-backport-modules with no change.

I even tried kernel boot options: pci=acpi & clocksource=jiffies
The later makes throughput of usb a whole lot faster 15MB/s instead of 6MB/s, but crashes of iwlagn still persist ;(

[decoder (decoder-ubuntu)]

This bug was most likely fixed in the mainstream kernel for version 2.6.33-rc3 (see https://bugzilla.kernel.org/show_bug.cgi?id=14141)

Please backport the respective patch from vanilla kernel GIT repository to Karmic to fix this issue.

[decoder (decoder-ubuntu)]

I can also confirm this bug for Lucid Beta, using kernel package 2.6.32.19.20

[penalvch (penalvch)]

Khem Raj, thank you for reporting this and helping make Ubuntu better. Karmic reached EOL on April 30, 2011.
Please see this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We were wondering if this is still an issue in a supported release? If so, could you please test for this with the latest development release of Ubuntu? ISO CD images are available from http://cdimage.ubuntu.com/releases/ .

If it remains an issue, could you please run the following command in the development release from a Terminal (Applications->Accessories->Terminal), as it will automatically gather and attach updated debug information to this report:

apport-collect -p linux <replace-with-bug-number>

Also, could you please test the latest upstream kernel available following https://wiki.ubuntu.com/KernelMainlineBuilds ? It will allow additional upstream developers to examine the issue. Please do not test the kernel in the daily folder, but the one all the way at the bottom. Once you've tested the upstream kernel, please comment on which kernel version specifically you tested and remove the tag:
needs-upstream-testing

This can be done by clicking on the yellow pencil icon next to the tag located at the bottom of the bug description and deleting the text:
needs-upstream-testing

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.

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

where VERSION-NUMBER is the version number of the kernel you tested.

If you are unable to test the mainline kernel, please comment as to why specifically you were unable to test it and add the following tags:
kernel-unable-to-test-upstream
kernel-unable-to-test-upstream-VERSION-NUMBER

where VERSION-NUMBER is the version number of the kernel you tested.

Please let us know your results. Thank you for your understanding.

Helpful Bug Reporting Links:
https://help.ubuntu.com/community/ReportingBugs#Bug_Reporting_Etiquette
https://help.ubuntu.com/community/ReportingBugs#A3._Make_sure_the_bug_hasn.27t_already_been_reported
https://help.ubuntu.com/community/ReportingBugs#Adding_Apport_Debug_Information_to_an_Existing_Launchpad_Bug
https://help.ubuntu.com/community/ReportingBugs#Adding_Additional_Attachments_to_an_Existing_Launchpad_Bug

[Po-Hsu Lin (cypressyew)]

Closing this bug with Won't fix as this kernel / release is no longer supported.
Please feel free to open a new bug report if you're still experiencing this on a newer release (Bionic 18.04.3 / Disco 19.04)
Thanks!