unable to connect to wifi

[Naman Verma]

My ThinkPad T430 ran very good with no issues on 1804 lts. After upgrading it is not connecting to wifi.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: linux-image-5.4.0-42-generic 5.4.0-42.46
ProcVersionSignature: Ubuntu 5.4.0-42.46-generic 5.4.44
Uname: Linux 5.4.0-42-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.6
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: naman 1446 F.... pulseaudio
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Tue Aug 11 11:59:57 2020
InstallationDate: Installed on 2020-06-21 (50 days ago)
InstallationMedia: Ubuntu 18.04.3 LTS "Bionic Beaver" - Release amd64 (20190805)
MachineType: LENOVO 23501E3
ProcFB: 0 i915drmfb
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.4.0-42-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-5.4.0-42-generic N/A
 linux-backports-modules-5.4.0-42-generic N/A
 linux-firmware 1.187.2
SourcePackage: linux
UpgradeStatus: Upgraded to focal on 2020-08-02 (8 days ago)
dmi.bios.date: 03/08/2013
dmi.bios.vendor: LENOVO
dmi.bios.version: G1ET93WW (2.53 )
dmi.board.asset.tag: Not Available
dmi.board.name: 23501E3
dmi.board.vendor: LENOVO
dmi.board.version: Win8 Pro DPK TPG
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvrG1ET93WW(2.53):bd03/08/2013:svnLENOVO:pn23501E3:pvrThinkPadT430:rvnLENOVO:rn23501E3:rvrWin8ProDPKTPG:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.family: ThinkPad T430
dmi.product.name: 23501E3
dmi.product.sku: LENOVO_MT_2350
dmi.product.version: ThinkPad T430
dmi.sys.vendor: LENOVO

[Kai-Heng Feng (kaihengfeng)]

Only after system sleep?

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This change was made by a bot.

[Alex Hung (alexhung)]

Additional information with kaihengfeng's comment.

dmesg shows wifi stops working after suspend and resume. wifi driver also tried to restart hardware but failed:

[ 459.548998] e1000e: enp0s25 NIC Link is Down
[ 461.601935] iwlwifi 0000:03:00.0: Error sending REPLY_SCAN_ABORT_CMD: time out after 2000ms.
...
[ 461.865575] ieee80211 phy0: Hardware restart was requested
...
[ 467.757292] Hardware became unavailable during restart.

If this is the case, please try to re-initialize wifi driver by "sudo modprobe -r iwlwifi; sudo modprobe iwlwifi".

[Alex Hung (alexhung)]

Since this system is upgraded from 18.04, it is also worthwhile to boot 20.04.1 USB and verify this issue. Suspend and resume can be tested in live session as well.