touchpad not working after upgrade to 5.0.0-31 kernel

[Compinfer]

touchpad is not avaliable after upgrade to linux-image-5.0.0-31-generic
It works on 5.0.0-29 kernel.
Laptop model: MSI GS40 6QE-091RU

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: linux-image-5.0.0-31-generic 5.0.0-31.33
ProcVersionSignature: Ubuntu 5.0.0-31.33-generic 5.0.21
Uname: Linux 5.0.0-31-generic x86_64
ApportVersion: 2.20.10-0ubuntu27.1
Architecture: amd64
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: vkovalen 1900 F.... pulseaudio
CurrentDesktop: Unity:Unity7:ubuntu
Date: Tue Oct 8 10:37:31 2019
InstallationDate: Installed on 2019-05-18 (142 days ago)
InstallationMedia: Ubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
Lsusb:
 Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
 Bus 001 Device 003: ID 0bda:0129 Realtek Semiconductor Corp. RTS5129 Card Reader Controller
 Bus 001 Device 002: ID 046d:c52b Logitech, Inc. Unifying Receiver
 Bus 001 Device 004: ID 0cf3:e300 Qualcomm Atheros Communications
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
MachineType: Micro-Star International Co., Ltd. GS40 6QE Phantom
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.0.0-31-generic root=UUID=84c66d52-4ba6-49d7-8d50-e582f93d9b5c ro quiet nouveau.modeset=0 rd.driver.blacklist=nouveau acpi_osi=! "acpi_osi=Windows 2009" acpi_backlight=vendor resume=UUID=f7c3465a-6b62-428f-8477-67b678e6fe6e
RelatedPackageVersions:
 linux-restricted-modules-5.0.0-31-generic N/A
 linux-backports-modules-5.0.0-31-generic N/A
 linux-firmware 1.178.3
SourcePackage: linux
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 01/15/2018
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: E14A1IMS.113
dmi.board.asset.tag: Default string
dmi.board.name: MS-14A1
dmi.board.vendor: Micro-Star International Co., Ltd.
dmi.board.version: REV:0.C
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 10
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrE14A1IMS.113:bd01/15/2018:svnMicro-StarInternationalCo.,Ltd.:pnGS406QEPhantom:pvrREV0.C:rvnMicro-StarInternationalCo.,Ltd.:rnMS-14A1:rvrREV0.C:cvnDefaultstring:ct10:cvrDefaultstring:
dmi.product.family: Default string
dmi.product.name: GS40 6QE Phantom
dmi.product.sku: Default string
dmi.product.version: REV:0.C
dmi.sys.vendor: Micro-Star International Co., Ltd.

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

This change was made by a bot.

[Compinfer (nvkinf)]

missing device:
I: Bus=0011 Vendor=0002 Product=000e Version=0000
N: Name="ETPS/2 Elantech Touchpad"
P: Phys=isa0060/serio1/input0
S: Sysfs=/devices/platform/i8042/serio1/input/input6
U: Uniq=
H: Handlers=mouse0 event5
B: PROP=5
B: EV=b
B: KEY=e420 10000 0 0 0 0
B: ABS=661800011000003

[Kai-Heng Feng (kaihengfeng)]

Similar to LP: #1846857?

[Compinfer (nvkinf)]

No, this is different from #1846857.
In my case touchpad is missing completely.

I also tested under the mainline 5.4 kernel, and it doesn't work.

I think, it is similar to #1847151 , we both have MSI laptops with Elantech touchpad.

[Compinfer (nvkinf)]

Tested also under Eoan last daily buld (kernel 5.3.0-13), touchpad doesn't work.

[Compinfer (nvkinf)]

A workaround found:
to add the following to the kernel boot arguments:
psmouse.elantech_smbus=0

[Kai-Heng Feng (kaihengfeng)]

Should be fixed in 5.0.0-32.

[Compinfer (nvkinf)]

Thank you for the fast solution.
Indeed, in 5.0.0-32 kernel the problem is solved, so in disco the bug is solved.

Unfortunately, in the released eoan the bug is still present (5.3.0-18).