Screen periodically blanks for a couple of seconds with kernel 6.8.0

[Paddy Landau]

This is frustrating. First, kernel 6.5.0 removed the ability to adjust the screen brightness (my thread).

Now, kernel 6.8.0 blanks the screen for a second or two at apparently random times, anywhere between one second and several minutes between each blanking. It did so several times during the time it took for me to write this post!

I haven't been able to find a bug report for this, so I'm wondering if you know anything about it, and if you know of a way to diagnose and fix it, please?

$ lsb_release --all
No LSB modules are available.
Distributor ID:    UbuntuDescription:    Ubuntu 22.04.4 LTS
Release:    22.04
Codename:    jammy

$ uname --all
Linux glinda 6.8.0-40-generic #40~22.04.3-Ubuntu SMP PREEMPT_DYNAMIC Tue Jul 30 17:30:19 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

$ sudo lshw -numeric -C display
  *-display                 
       description: VGA compatible controller
       product: CometLake-S GT2 [UHD Graphics 630] [8086:9BC5]
       vendor: Intel Corporation [8086]
       physical id: 2
       bus info: pci@0000:00:02.0
       logical name: /dev/fb0
       version: 05
       width: 64 bits
       clock: 33MHz
       capabilities: pciexpress msi pm vga_controller bus_master cap_list rom fb
       configuration: depth=32 driver=i915 latency=0 resolution=1920,1080
       resources: irq:152 memory:c1000000-c1ffffff memory:d0000000-dfffffff ioport:3000(size=64) memory:c0000-dffff

Thank you

[currentshaft]

zx

[Paddy Landau]

Any errors in dmesg or journalctl output when this happens?

I can't see anything in journalctl, but each time it happens, this is what shows in dmesg:

[ 7912.265657] usb 1-9: USB disconnect, device number 17
[ 7912.456384] [UFW BLOCK] IN=wlo1 OUT= MAC=cc:d9:ac:5c:ae:40:08:2e:5f:f1:00:63:86:dd SRC=fe80:0000:0000:0000:0a2e:5fff:fef1:0063 DST=fe80:0000:0000:0000:c68a:3c94:7f1b:cbfa LEN=2330 TC=0 HOPLIMIT=64 FLOWLBL=0 PROTO=UDP SPT=3702 DPT=43887 LEN=2290 
[ 7913.557402] usb 1-9: new full-speed USB device number 18 using xhci_hcd
[ 7913.685271] usb 1-9: New USB device found, idVendor=1fd2, idProduct=8105, bcdDevice= 1.00
[ 7913.685275] usb 1-9: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 7913.685277] usb 1-9: Product: LGDisplay Incell Touch
[ 7913.685278] usb 1-9: Manufacturer: Melfas
[ 7913.690820] input: Melfas LGDisplay Incell Touch as /devices/pci0000:00/0000:00:14.0/usb1/1-9/1-9:1.0/0003:1FD2:8105.001F/input/input45
[ 7913.691112] hid-multitouch 0003:1FD2:8105.001F: input,hidraw2: USB HID v1.11 Device [Melfas LGDisplay Incell Touch] on usb-0000:00:14.0-9/input0
[ 7913.691960] hid-generic 0003:1FD2:8105.0020: hiddev1,hidraw3: USB HID v1.11 Device [Melfas LGDisplay Incell Touch] on usb-0000:00:14.0-9/input1

Each time, the USB device number (lines 1 and 3) increments by 1, and there are varying numbers of UFW_BLOCK (sometimes just one, sometimes more).

[#&thj^%]

Hi Paddy, have you tried this yet

xset -dpms

I didn't like kernel 6.8.0 too many oddities, YMMV

[Paddy Landau]

Hi Paddy, have you tried this yet

xset -dpms

I've just run it. I'll report back when either sufficient time has passed to feel confident that it has worked, or the problem recurs.

Do I have to run this each time I reboot, or is it set permanently until I change it back?

I didn't like kernel 6.8.0 too many oddities, YMMV

It was part of the standard updates for 22.04 with Pro enabled.

[Paddy Landau]

Unfortunately, xset -dpms hasn't worked

[currentshaft]

@

[#&thj^%]

It was part of the standard updates for 22.04 with Pro enabled.

I know
I quickly jumped to kernel 6.10, and you know I'm not suggesting that you do though.
I'm not sure a bug report would matter at this point: https://duckduckgo.com/?q=+Screen+pe...=v358-1&ia=web
If I understand the buzz lately (and it is just hearsay currently) they are thinking 6.9 will land in jammy at a later time. For now we battle on.

Thanks for trying xset though, and I hope it was used in a X-Session and not wayland.

[Paddy Landau]

The UFW line is benign (a device on your local network is doing service discovery).

Thank you.

This is a laptop screen, right? Are there any available firmware updates with "fwupdmgr install"?

No, this is a desktop, OptiPlex 5480 AIO All-In-One. It has a touchscreen.

There are no pending fwupdmgr updates. I have had several since I first purchased the machine. The last update was five days ago:

$ fwupdmgr get-history
OptiPlex 5480 AIO
│
└─System Firmware:
  │   Device ID:          a45df35ac0e948ee180fe216a5f703f32dda163f
  │   Previous version:   1.32.0
  │   Update State:       Success
  │   Last modified:      2024-08-09 13:32
  │   GUID:               f5d534f4-f4c3-4821-a863-285d9dd3e013
  │   Device Flags:       • Internal device
  │                       • Updatable
  │                       • System requires external power source
  │                       • Supported on remote server
  │                       • Needs a reboot after installation
  │                       • Reported to remote server
  │                       • Cryptographic hash verification is available
  │                       • Device is usable for the duration of the update
  │ 
  └─OptiPlex 5480 AIO:
        New version:      1.33.0
        Remote ID:        lvfs
        Release ID:       95125
        Summary:          Firmware for the Dell OptiPlex 5480 AIO
        License:          Proprietary
        Size:             23.7 MB
        Created:          2024-07-04
        Urgency:          Critical
        Vendor:           Dell
        Description:      
        Dell Technologies highly recommends applying this important update as soon as possible. The update contains critical bug fixes and changes to improve functionality, reliability, and stability of your Dell system. It may include security fixes and other feature enhancements.

[Paddy Landau]

I quickly jumped to kernel 6.10, and you know I'm not suggesting that you do though.

Well, I could try! I don't know how to install it on 22.04, though.

I'm not sure a bug report would matter at this point: https://duckduckgo.com/?q=+Screen+pe...=v358-1&ia=web

None of those seems to relate to my problem.

If I understand the buzz lately (and it is just hearsay currently) they are thinking 6.9 will land in jammy at a later time. For now we battle on.

Thanks for trying xset though, and I hope it was used in a X-Session and not wayland.

Yes, X11. Wayland isn't ready for me yet — it can't do what I need it to do.