Random flickering with Intel i915 (Gen9 GPUs in 6th-8th gen CPUs) on Linux 6.8

[Eugene San]

SRU Justification

[Impact]
The flickering predominantly occurs when the mouse cursor is in the bottom quarter of the screen and stops when the cursor leaves this area.
Extensive testing across various kernel versions revealed that the issue became apparent from kernel version 6.8.0 onward, correlating with the mentioned configuration changes, CONFIG_INTEL_IOMMU_DEFAULT_ON and CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON.
The problem persists in the latest drm tip.

[Fix]
As an immediate workaround, adding 'intel_iommu=igfx_off' to the kernel command line has been found to effectively eliminate the flickering issue.
This patch proposes the same behavior as 'intel_iommu=igfx_off' and apply the rule to all Intel SKL GPU IDs.

[Test]
1. Boot up to desktop with 6.8.0-x kernels
2. Moving cursor around the desktop
3. There should be no flicker while cursor is moving

[Where problems could occur]
For virtualized environments using hardware-assisted virtualization for graphics (such as VFIO or mediated pass-through), disabling IOMMU for graphics could either disable these features or reduce their security and efficiency.
Usually, users pass the 'intel_iommu=on' by themselves when they are using related features. So, the impact of this change is minimal.

===========

After migrating Mantic 23.10 install to Linux 6.8.0, I am experiencing heavy flickering at random.
It happens after a moderate to heavy on screen activity like window switching, scrolling etc.
It never happens when playing video or when there is no interaction using keyboard/pointer.

It tend to happen when the mouse cursor is in the bottom quarter of the screen and stops immediately when the cursor leaves that screen region.
Around the same time the following appears in kernel log:
kernel: i915 0000:00:02.0: [drm] *ERROR* CPU pipe A FIFO underrun

Happens on both X11 and Wayland on both KDE plasma and Mate (though less).

I first encountered the issue with Linux 6.8.0-11 and it still happens with Ubunutu's 6.8.0-28 and Mainline 6.8.7.
Kernels 6.6, 6.5, 6.1 and older did not have that issue.

Hardware is: Dell XPS 9350, Vendor Intel, Driver i915, Skylake GT2 [HD Graphics 520]
Software: Ubuntu 23.10, KDE Plasma 5.27.10 / Mate 1.26

Attaching kernel log for 6.8.0-28

[lotuspsychje (lotuspsychje)]

Thank you for filing this bug and make Ubuntu better!

In order to collect all your system info and relevant logs

please execute: apport-collect 2062951 from your terminal

so the developers can start debug your bug a better way

Thank you!

[Eugene San (eugenesan)]

Update:
I did some preliminary testing and it seems like adding "intel_idle.max_cstate=4" to cmdline resolves the issue but probably at the power efficiency cost.

I also tried "i915.enable_psr=0" but it didn't help just made the flickering a slightly different.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Leon Williams (leonwilliams)]

I've tried adding "intel_idle.max_cstate=4" too but it didn't fix anything for me.
Both KDE Plasma and Xfce have the same behavior.

I'm also on a Skylake GT2 [HD Graphics 520] - no issues on 23.10 as I didn't change kernel, but 24.04 with kernel 6.8 is where I'm experiencing this.

[Eugene San (eugenesan)]

Update:
Still happens on Kubuntu 24.04 with Linux 6.8.0-32 (6.8.4).

[Leon Williams (leonwilliams)]

This seems to be related to the newer Intel Xe driver included with kernel 6.8.x as it only occurs when the driver is enabled. When using nomodeset in grub, there are no issues (besides losing brightness controls etc from no driver being loaded).

[Davron (davronjon)]

This has happened since the very first day of a clean installation on a pc. Thought since it might not have downloaded all drivers yet, maybe it would get fixed over time, but it still persists. Any way to fix it manually?

# System Details Report
---

## Report details
- **Date generated:** 2024-05-18 02:43:44

## Hardware Information:
- **Hardware Model:** Dell Inc. Vostro 3590
- **Memory:** 8,0 GiB
- **Processor:** Intel® Core™ i5-10210U × 8
- **Graphics:** Intel® UHD Graphics (CML GT2)
- **Disk Capacity:** 240,1 GB

## Software Information:
- **Firmware Version:** 1.27.0
- **OS Name:** Ubuntu 24.04 LTS
- **OS Build:** (null)
- **OS Type:** 64-bit
- **GNOME Version:** 46
- **Windowing System:** Wayland
- **Kernel Version:** Linux 6.8.0-31-generic

[Leon Williams (leonwilliams)]

@Davron - downgrading the kernel to 6.7 should work for now, but I just went back to 22.04 as I also had issues with laptop shutdown state etc

Also worth clicking the "this bug affects me" thing at the top as I don't think devs will bother unless the issue gets some visibility.

Seen quite a few others on Reddit with same or similar issues so it definitely affects more than is showing here.

[Asif Nawaz (asiftech)]

## Summary:
Random screen glitches appearing as horizontal lines flickering from left to right on a clean install of Ubuntu 24.04.

## Description:

I experience random screen flickering on a clean install of Ubuntu 24.04. The glitches appear as horizontal lines that flicker from the left side of the screen towards the right at irregular intervals. This issue does not occur all the time, but happens sporadically.

System Information::
System: Dell Latitude 3379
Processor: Intel Core i3-6006U
Graphics Card: Intel HD Graphics 520
Memory: 8.0 GiB
windwoing Sytem: Wayland
kernal : 6.8

[Oibaf (oibaf)]

See also similar bug 2064189.

[Kenneth W Green (vertee)]

Ive never had the issue with any distro.

So okay the bug is confirmed and it has a duplicate but in none of the reports, duplicates or otherwise, can I find a fix.

Running 24.04 on a Dell Insperion 9555 Intel i7 64/16Gig 1tb Radeon graphics

Does a fix exist for this bug ??

[Eugene San (eugenesan)]

Proper fix might come in future releases of Linux kernel.

For now adding "intel_idle.max_cstate=4" to the kernel command line should work at expense of a minor power consumption.
See https://wiki.ubuntu.com/Kernel/KernelBootParameters#Permanently_Add_a_Kernel_Boot_Parameter for instructions.

[Kenneth W Green (vertee)]

Hi, OK I have tried both temporary and permanent grub boot changes with modified intel_idle.max_cstate=2 and 4 and on all occasions after grub update and reboot the boot splash page is steady the login page flickers badly and the desktop settles but still flickers.

Tks for the help but unfortunately workaround does not work on the Dell Insperion 955 Intel i7 64/16Gb 1tb Radeon GPU. Ive include a snap shot of my patched grub boot file.

[Oibaf (oibaf)]

In bug 1958191 (which looks similar and may or may not be the same issue) there is a slightly different workaround:

"adding the kernel parameter i915.enable_dc=0 intel_idle.max_cstate=2 fixed this"

[Eugene San (eugenesan)]

@vartee

This bug is Intel i915 specific.

I am afraid you are experiencing AMDGPU related issue and should look for related open bug or open one by your self.

P.S.
I remember having similar flickering issues with AMDGPU and adding "amdgpu.dcdebugmask=0x10" helped. Note, it was completely different hardware and kernel.

[Kenneth W Green (vertee)]

I have back tracked to the duplicate bug https://bugs.launchpad.net/bugs/1958191 and followed the suggested fix, which was patch grub boot;-

Patched my grub boot file GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_dc=0 intel_idle.max_cstate=2"

sudo update-grub and restarted machine

Works a treat no more screen flicker after upgrade to 24.04 and several reboots just to be sure fix worked on Dell Insperion 9555 i7 64/16Gb 1Tb Radeon GPU.

[Danijel (dadoghost)]

Same problem here:

ThinkPad T470s

00:02.0 VGA compatible controller: Intel Corporation HD Graphics 620 (rev 02)

Distributor ID: Ubuntu
Description: Ubuntu 24.04 LTS
Release: 24.04
Codename: noble

filename: /lib/modules/6.8.0-31-generic/kernel/drivers/gpu/drm/i915/i915.ko.zst
license: GPL and additional rights
description: Intel Graphics
author: Intel Corporation
author: Tungsten Graphics, Inc.
import_ns: DMA_BUF
firmware: i915/mtl_gsc_1.bin

[cypherscouter (cypherscouter)]

I'm having a similar issue https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2062950

[James McKenzie (jamesps)]

I think I'm having the same issue

I am running TPM+FDE on Ubuntu 24.04. I tried to apply the workaround suggested with following command:
snap set system system.kernel.dangerous-cmdline-append="i915.enable_dc=0 intel_idle.max_cstate=2"

But I'm still seeing the same after a reboot. In my case, I have my laptop screen and external monitor in extend mode. The "flickering" is occurring only on the laptop screen (which is NOT set as the primary).

As others have described, mouse position seems to be a trigger for this, but not always in the same position.

[Christoph Wolk (spikespiegel-gmx)]

Same problem here, using Kubuntu 24.04 on a fresh install (with Xorg). Intermittent flickering of the whole screen; I could not determine a specific pattern that caused it. Happened several times per day, usually briefly but sometimes for several seconds.

Adding "i915.enable_dc=0 intel_idle.max_cstate=2" to the grub defaults fixes the issue completely; no further flickering observed in about a week of usage.

System: Thinkpad T470

lspci -s 00:02.0
00:02.0 VGA compatible controller: Intel Corporation HD Graphics 620 (rev 02)

Let me know if any information or testing I could provide would help fix this for others.

[malek (malek2662)]

Transitioning from Manjaro to Ubuntu #Fix_Available

I had been experiencing some issues with Manjaro, so I finally decided to switch to Ubuntu. Two days ago, I installed Ubuntu 24.04. During the system update and graphic driver installation, within less than an hour of using the device, I noticed that the screen was flickering and disappearing when I moved the mouse. Initially, I thought I had broken the system (haha). After several attempts to fix it, tracing my steps, and uninstalling the latest packages that might have caused the problem, I finally reinstalled the system again.

To my dismay, after installing the new system and even before starting to update it, the flickering returned. Damn. I’m just venting a bit, don’t mind me; I had a really bad day.

In the end, I can confirm that adding these parameters to GRUB resolved the issue for me, perhaps at the cost of a bit of heat, but it’s a good workaround until the bug is fixed:

[ GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_dc=0 intel_idle.max_cstate=2" ]
Steps to Add Parameters to GRUB

    - Open GRUB configuration file for editing:
    [ sudo nano /etc/default/grub ]

    - Modify the GRUB_CMDLINE_LINUX_DEFAULT line:
    [ GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_dc=0 intel_idle.max_cstate=2"]

    - Update GRUB configuration:
    [ sudo update-grub ]

My Laptop Specifications

    Brand and Model: Dell
    Processor: Intel Core i7 (7th Generation)
    Graphics Card: Intel HD Graphics 620

[George-t (george-t)]

I recently upgraded from 22.04 to 24.04 (through v23.10 via do-release-upgrade) and now have symptoms similar to those described (flickering of windows, especially when moving them and I also get screen lockup when trying to dock a window to top/sides of desktop). Running two displays on my dell laptop, one via HDMI and the internal as well.

## Report details
- **Date generated:** 2024-06-01 07:00:47

## Hardware Information:
- **Hardware Model:** Precision 5510
- **Memory:** 31Gi
- **Processor:** Intel(R) Xeon(R) CPU E3-1505M v5 @ 2.80GHz
- **Graphics:** Intel Corporation HD Graphics P530 (rev 06)
- **Disk Capacity:** 2.4T

## Software Information:
- **Firmware Version:** 1.23.0
- **OS Name:** Ubuntu 24.04 LTS
- **OS Build:** 24.04
- **OS Type:** x86_64
- **GNOME Version:** 46.0
- **Windowing System:** x11
- **Kernel Version:** 6.8.0-31-generic

[Eugene San (eugenesan)]

People suggest adding "i915.enable_dc=0 intel_idle.max_cstate=2" to the cmdline but for my hardware "intel_idle.max_cstate=4" is sufficient.
I believe higher max_cstate will result in lower power consumption and enable_dc is not needed.

[J&B (jibejibejb)]

same issue
intel hd530

[Daniel van Vugt (vanvugt)]

Not just Skylake. The duplicates I'm seeing reported from Noble machines are from Comet Lake and Kaby Lake. So all Intel "Gen9" GPUs.

[William MacGhee (macghee)]

For what it is worth my laptop too. An old Lenovo Thinkpad T460s.
The apport report case is closed..
tried using older kenel on grub load, didn't really help.

here is output of lsbci

00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers (rev 08)
00:02.0 VGA compatible controller: Intel Corporation Skylake GT2 [HD Graphics 520] (rev 07)
00:08.0 System peripheral: Intel Corporation Xeon E3-1200 v5/v6 / E3-1500 v5 / 6th/7th/8th Gen Core Processor Gaussian Mixture Model
00:14.0 USB controller: Intel Corporation Sunrise Point-LP USB 3.0 xHCI Controller (rev 21)
00:14.2 Signal processing controller: Intel Corporation Sunrise Point-LP Thermal subsystem (rev 21)
00:16.0 Communication controller: Intel Corporation Sunrise Point-LP CSME HECI #1 (rev 21)
00:16.3 Serial controller: Intel Corporation Sunrise Point-LP Active Management Technology - SOL (rev 21)
00:1c.0 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #1 (rev f1)
00:1c.2 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #3 (rev f1)
00:1c.4 PCI bridge: Intel Corporation Sunrise Point-LP PCI Express Root Port #5 (rev f1)
00:1f.0 ISA bridge: Intel Corporation Sunrise Point-LP LPC Controller (rev 21)
00:1f.2 Memory controller: Intel Corporation Sunrise Point-LP PMC (rev 21)
00:1f.3 Audio device: Intel Corporation Sunrise Point-LP HD Audio (rev 21)
00:1f.4 SMBus: Intel Corporation Sunrise Point-LP SMBus (rev 21)
00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection I219-LM (rev 21)
02:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTS522A PCI Express Card Reader (rev 01)
04:00.0 Network controller: Intel Corporation Wireless 8260 (rev 3a)
05:00.0 Non-Volatile memory controller: Micron/Crucial Technology P2 [Nick P2] / P3 / P3 Plus NVMe PCIe SSD (DRAM-less) (rev 01)

[William MacGhee (macghee)]

Oh having read the manpage for lspci it suggests a more comprehensive output.
Again Lenovo T460s, trouble started on upgrade to 24.04 from 20

00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers (rev 08)
 Subsystem: Lenovo Xeon E3-1200 v5/E3-1500 v5/6th Gen Core Processor Host Bridge/DRAM Registers
 Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
 Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 IOMMU group: 1
 Capabilities: [e0] Vendor Specific Information: Len=10 <?>
 Kernel driver in use: skl_uncore
00: 86 80 04 19 06 00 90 00 08 00 00 06 00 00 00 00
10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
20: 00 00 00 00 00 00 00 00 00 00 00 00 aa 17 33 22
30: 00 00 00 00 e0 00 00 00 00 00 00 00 00 00 00 00
40: 01 90 d1 fe 00 00 00 00 01 00 d1 fe 00 00 00 00
50: c1 01 00 00 31 80 00 00 47 00 70 dc a7 00 00 d9
60: 05 00 00 f8 00 00 00 00 01 80 d1 fe 00 00 00 00
70: 00 00 00 fe 01 00 00 00 00 0c 00 fe 7f 00 00 00
80: 10 11 11 11 11 11 11 00 1a 00 00 00 00 00 00 00
90: 01 00 00 fe 01 00 00 00 01 00 70 21 02 00 00 00
a0: 01 00 00 00 02 00 00 00 01 00 80 21 02 00 00 00
b0: 01 00 80 da 01 00 00 da 01 00 00 d9 01 00 80 dc
c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
e0: 09 00 10 01 85 66 61 7a dc 80 15 14 00 c0 06 00
f0: 00 00 00 00 c8 0f 03 00 00 00 00 00 00 00 00 00

00:02.0 VGA compatible controller: Intel Corporation Skylake GT2 [HD Graphics 520] (rev 07) (prog-if 00 [VGA controller])
 Subsystem: Lenovo Skylake GT2 [HD Graphics 520]
 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
 Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
 Latency: 0
 Interrupt: pin A routed to IRQ 139
 IOMMU group: 0
 Region 0: Memory at f0000000 (64-bit, non-prefetchable) [size=16M]
 Region 2: Memory at e0000000 (64-bit, prefetchable) [size=256M]
 Region 4: I/O ports at e000 [size=64]
 Expansion ROM at 000c0000 [virtual] [disabled] [size=128K]
 Capabilities: [40] Vendor Specific Information: Len=0c <?>
 Capabilities: [70] Express (v2) Root Complex Integrated Endpoint, MSI 00
  DevCap: MaxPayload 128 bytes, PhantFunc 0
   ExtTag- RBE+ FLReset+
  DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
   RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop- FLReset-
   MaxPayload 128 bytes, MaxReadReq 128 bytes
  DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr- TransPend-
  DevCap2: Completion Timeout: Not Supported, TimeoutDis- NROPrPrP- LTR-
    10BitTagComp- 10BitTagReq- OBFF Not Supported, ExtFmt- EETLPPrefix-
    EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
    FRS-
    AtomicOpsCap: 32bit- 64bit- 128bitCAS-
  DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- LTR- 10BitTagReq- OBFF Disabled,
    AtomicOpsCtl: ReqEn-
 Capabilities: [ac] MSI: Enable+ Count=1/1 Maskable- 64bit-
  Address: fee00018 Data: 0000
 Capabilities: [d0] Power Management version 2
  Flags: PMEClk- DSI+ D1- D2- AuxCurrent=0mA PME(D0-...

[Eugene San (eugenesan)]

I've been testing kernel 6.8.0-38 (from proposed) and while it's not fixing the problem completely, at least on my hardware it is somewhat better. The flickering happens once in 2-3 days and is very brief (~1s).

I can't recommend using kernel 6.8.0-38 since it shows unhealthy amount of warnings related to iommu.
But assuming kernel team fixes the iommu issues, we might have a major relief with the following release.

[arnoldthebat (tony-ditchfield)]

intel_idle.max_cstate=4 definitely not working for me so will try intel_idle.max_cstate=2 as folks have noted and see what occurs

00:02.0 VGA compatible controller: Intel Corporation CometLake-H GT2 [UHD Graphics] (rev 05) (prog-if 00 [VGA controller])
 DeviceName: Onboard IGD
 Subsystem: Hewlett-Packard Company CometLake-H GT2 [UHD Graphics]
 Flags: bus master, fast devsel, latency 0, IRQ 218, IOMMU group 0
 Memory at df000000 (64-bit, non-prefetchable) [size=16M]
 Memory at a0000000 (64-bit, prefetchable) [size=256M]
 I/O ports at 3000 [size=64]
 Expansion ROM at 000c0000 [virtual] [disabled] [size=128K]
 Capabilities: [40] Vendor Specific Information: Len=0c <?>
 Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00
 Capabilities: [ac] MSI: Enable+ Count=1/1 Maskable- 64bit-
 Capabilities: [d0] Power Management version 2
 Capabilities: [100] Process Address Space ID (PASID)
 Capabilities: [200] Address Translation Service (ATS)
 Capabilities: [300] Page Request Interface (PRI)
 Kernel driver in use: i915
 Kernel modules: i915

[AceLan Kao (acelankao)]

Do you ever try drm-tip kernel to see if there is a fix in the upstream?
https://kernel.ubuntu.com/mainline/drm-tip/

[Daniel van Vugt (vanvugt)]

It doesn't affect me, but currently 28 other people are saying it affects them so I'm sure someone can try that.

[Eugene San (eugenesan)]

@acelankao
Last mainline version I tried was 6.8.7 and at the time it was as bad as on 6.8.0-11.

Unfortunately, on my hardware, bisecting/testing this bug would take unreasonable amount of time and risk running bleeding edge kernel since even with 6.8.0-35 it happens only once in 1 to 3 days.

I hope someone with more "affected" hardware will be able to test latest drm-tip.

[arnoldthebat (tony-ditchfield)]

No change using intel_idle.max_cstate=2

It does look like its affected by cursor position as @eugenesan noted in an earlier post.

Anecdotally, and supporting the cstate argument a little, running on battery also seems to worsen the problem slightly.

Still struggling to find a definitive trigger however.

[J&B (jibejibejb)]

@acelankao

I have tried 6.10.0-061000rc2drmtip20240604-generic, still have this problem.

[Adrian Elliott (adrianelliott1981)]

I'm running Dell Latitude 7390 with Intel UHD Graphics 620 (8350U). So 8th Gen rather than 9th. I get occasional glitching, usually on battery power and when scrolling, and always when pointer is in the bottom right of screen. I did try the kernel params listed here (i915.enable_dc=0 intel_idle.max_cstate=2, intel_idle.max_cstate=4) and this did not resolve. I have used Debian 12 and Fedora 40 on the same hardware and did not observe this. The behaviour has occurred when using Firefox (snap), VSCode (deb), Chrome (deb) and . Its not super intrusive on my hardware but it is annoying.

[Daniel van Vugt (vanvugt)]

The 8350U has a Gen9 GPU:
https://en.wikipedia.org/wiki/List_of_Intel_graphics_processing_units#Gen9

[Gopan (gperu)]

Affects me too in Ubuntu 22.04 updated.
Linux gp-hp 6.8.0-35-generic
AMD Radeon(TM) Graphic depth=32 driver=amdgpu latency=0

[Adrián Flotte (adr7nf442)]

Disabling "C states" in the BIOS works in my case, Idk how power consumption is affected for users who need greater battery life. (I don't use battery)...

[AceLan Kao (acelankao)]

Sorry for all the confusing, you don't need to verify other varient kernels.
You only need to try 6.8.0-48.48 which is the generic one and thank Eugene San he has verified and changed the required tag.

If adding "intel_iommu=igfx_off" works for you, but you still encounter the flicker issue with 6.8.0-48.48,
please attch your gfx info here, thanks.
   lspci -nnk | grep -A3 VGA

I'll start another round of SRU submition.

[Jeffrey Knockel (jeff250)]

> If adding "intel_iommu=igfx_off" works for you, but you still encounter the flicker issue with 6.8.0-48.48,
> please attch your gfx info here, thanks.
> lspci -nnk | grep -A3 VGA

$ lspci -nnk | grep -A3 VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation UHD Graphics 620 [8086:5917] (rev 07)
 DeviceName: Onboard IGD
 Subsystem: Dell UHD Graphics 620 [1028:081c]
 Kernel driver in use: i915

[R. van der van der Spank (rebbel)]

I have 6.8.0-48-generic #48~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Oct 7 11:24:13 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

Is that the proper kernel to test?

If I use "intel_iommu=igfx_off", then I have no flickering.
If I don't use it, then I have flickering.

00:02.0 VGA compatible controller [0300]: Intel Corporation CoffeeLake-H GT2 [UHD Graphics 630] [8086:3e9b]
 DeviceName: Onboard - Video
 Subsystem: Dell CoffeeLake-H GT2 [UHD Graphics 630] [1028:0870]
 Kernel driver in use: i915

Thank you for your answers!

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 6.8.0-48.48

---------------
linux (6.8.0-48.48) noble; urgency=medium

  * noble/linux: 6.8.0-48.48 -proposed tracker (LP: #2082437)

  * [SRU][Noble] Bad EPP defaults cause performance regressions on select Intel
    CPUs (LP: #2077470)
    - x86/cpu/vfm: Update arch/x86/include/asm/intel-family.h
    - cpufreq: intel_pstate: Allow model specific EPPs
    - cpufreq: intel_pstate: Update default EPPs for Meteor Lake
    - cpufreq: intel_pstate: Switch to new Intel CPU model defines
    - cpufreq: intel_pstate: Update Meteor Lake EPPs
    - cpufreq: intel_pstate: Use Meteor Lake EPPs for Arrow Lake
    - cpufreq: intel_pstate: Update Balance performance EPP for Emerald Rapids

  * power: Enable intel_rapl driver (LP: #2078834)
    - powercap: intel_rapl: Add support for ArrowLake-H platform

  * x86/vmware: Add TDX hypercall support (LP: #2077729)
    - x86/vmware: Introduce VMware hypercall API
    - x86/vmware: Add TDX hypercall support

  * Guest crashes post migration with migrate_misplaced_folio+0x4cc/0x5d0
    (LP: #2076866)
    - mm/mempolicy: use numa_node_id() instead of cpu_to_node()
    - mm/numa_balancing: allow migrate on protnone reference with
      MPOL_PREFERRED_MANY policy
    - mm: convert folio_estimated_sharers() to folio_likely_mapped_shared()
    - mm: factor out the numa mapping rebuilding into a new helper
    - mm: support multi-size THP numa balancing
    - mm/migrate: make migrate_misplaced_folio() return 0 on success
    - mm/migrate: move NUMA hinting fault folio isolation + checks under PTL
    - mm: fix possible OOB in numa_rebuild_large_mapping()

  * Add 'mm: hold PTL from the first PTE while reclaiming a large folio' to fix
    L2 Guest hang during LTP Test (LP: #2076147)
    - mm: hold PTL from the first PTE while reclaiming a large folio

  * KOP L2 guest fails to boot with 1 core - SMT8 topology (LP: #2070329)
    - KVM: PPC: Book3S HV nestedv2: Add DPDES support in helper library for Guest
      state buffer
    - KVM: PPC: Book3S HV nestedv2: Fix doorbell emulation

  * L2 Guest migration: continuously dumping while running NFS guest migration
    (LP: #2076406)
    - KVM: PPC: Book3S HV: Fix the set_one_reg for MMCR3
    - KVM: PPC: Book3S HV: Fix the get_one_reg of SDAR
    - KVM: PPC: Book3S HV: Add one-reg interface for DEXCR register
    - KVM: PPC: Book3S HV nestedv2: Keep nested guest DEXCR in sync
    - KVM: PPC: Book3S HV: Add one-reg interface for HASHKEYR register
    - KVM: PPC: Book3S HV nestedv2: Keep nested guest HASHKEYR in sync
    - KVM: PPC: Book3S HV: Add one-reg interface for HASHPKEYR register
    - KVM: PPC: Book3S HV nestedv2: Keep nested guest HASHPKEYR in sync

  * perf build disables tracepoint support (LP: #2076190)
    - [Packaging] perf: reenable libtraceevent

  * Please backport the more restrictive XSAVES deactivation for Zen1/2 arch
    (LP: #2077321)
    - x86/CPU/AMD: Improve the erratum 1386 workaround

  * Fix alsa scarlett2 driver in 6.8 (LP: #2076402)
    - ALSA: scarlett2: Move initialisation code lower in the source
    - ALSA: scarlett2: Implement handling of the ACK notification

  * rtw89: reset IDMEM mode to preven...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux-hwe-6.8 - 6.8.0-48.48~22.04.1

---------------
linux-hwe-6.8 (6.8.0-48.48~22.04.1) jammy; urgency=medium

  * jammy/linux-hwe-6.8: 6.8.0-48.48~22.04.1 -proposed tracker (LP: #2082436)

  [ Ubuntu: 6.8.0-48.48 ]

  * noble/linux: 6.8.0-48.48 -proposed tracker (LP: #2082437)
  * [SRU][Noble] Bad EPP defaults cause performance regressions on select Intel
    CPUs (LP: #2077470)
    - x86/cpu/vfm: Update arch/x86/include/asm/intel-family.h
    - cpufreq: intel_pstate: Allow model specific EPPs
    - cpufreq: intel_pstate: Update default EPPs for Meteor Lake
    - cpufreq: intel_pstate: Switch to new Intel CPU model defines
    - cpufreq: intel_pstate: Update Meteor Lake EPPs
    - cpufreq: intel_pstate: Use Meteor Lake EPPs for Arrow Lake
    - cpufreq: intel_pstate: Update Balance performance EPP for Emerald Rapids
  * power: Enable intel_rapl driver (LP: #2078834)
    - powercap: intel_rapl: Add support for ArrowLake-H platform
  * x86/vmware: Add TDX hypercall support (LP: #2077729)
    - x86/vmware: Introduce VMware hypercall API
    - x86/vmware: Add TDX hypercall support
  * Guest crashes post migration with migrate_misplaced_folio+0x4cc/0x5d0
    (LP: #2076866)
    - mm/mempolicy: use numa_node_id() instead of cpu_to_node()
    - mm/numa_balancing: allow migrate on protnone reference with
      MPOL_PREFERRED_MANY policy
    - mm: convert folio_estimated_sharers() to folio_likely_mapped_shared()
    - mm: factor out the numa mapping rebuilding into a new helper
    - mm: support multi-size THP numa balancing
    - mm/migrate: make migrate_misplaced_folio() return 0 on success
    - mm/migrate: move NUMA hinting fault folio isolation + checks under PTL
    - mm: fix possible OOB in numa_rebuild_large_mapping()
  * Add 'mm: hold PTL from the first PTE while reclaiming a large folio' to fix
    L2 Guest hang during LTP Test (LP: #2076147)
    - mm: hold PTL from the first PTE while reclaiming a large folio
  * KOP L2 guest fails to boot with 1 core - SMT8 topology (LP: #2070329)
    - KVM: PPC: Book3S HV nestedv2: Add DPDES support in helper library for Guest
      state buffer
    - KVM: PPC: Book3S HV nestedv2: Fix doorbell emulation
  * L2 Guest migration: continuously dumping while running NFS guest migration
    (LP: #2076406)
    - KVM: PPC: Book3S HV: Fix the set_one_reg for MMCR3
    - KVM: PPC: Book3S HV: Fix the get_one_reg of SDAR
    - KVM: PPC: Book3S HV: Add one-reg interface for DEXCR register
    - KVM: PPC: Book3S HV nestedv2: Keep nested guest DEXCR in sync
    - KVM: PPC: Book3S HV: Add one-reg interface for HASHKEYR register
    - KVM: PPC: Book3S HV nestedv2: Keep nested guest HASHKEYR in sync
    - KVM: PPC: Book3S HV: Add one-reg interface for HASHPKEYR register
    - KVM: PPC: Book3S HV nestedv2: Keep nested guest HASHPKEYR in sync
  * perf build disables tracepoint support (LP: #2076190)
    - [Packaging] perf: reenable libtraceevent
  * Please backport the more restrictive XSAVES deactivation for Zen1/2 arch
    (LP: #2077321)
    - x86/CPU/AMD: Improve the erratum 1386 workaround
  * Fix alsa scarlett2 driver in 6.8 (LP: #2076402)
    - ALSA: scarlett2: Move initialisation c...

[R. van der van der Spank (rebbel)]

I have 6.8.0-48-generic #48~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Oct 7 11:24:13 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

Do I have the correct version, because I still need "intel_iommu=igfx_off". If not, how do I install it?
Thank you for all of your effort.

[Jeffrey Knockel (jeff250)]

Hi @rebbel, the kernel version you cite is the "fixed" version, but it does not include a fix for *all* affected hardware. Since you have already provided in comment 116 the hardware info that AceLan requested, you have done everything you need to at this time. Hopefully AceLan can soon prepare another patch that encompasses a greater array of affected hardware.

[Bernard Moreton (bernard-moreton-1)]

The kernel upgrade to 6.8.0-47 made a noticeable improvement to the mouse/pointer problems on my Dell Inspiron, and 6.8.0-48 has now fixed most of them - thank you!

BUT I still have one problem left: for years I've had the touchpad disabled, and used a USB mouse, as being easier to control properly. Since the 24.04.1 LTS upgrade (and the 6.8 kernel), the touchpad has become sensitive to taps, so context menus appear frequently as my wrist moves over the touchpad, and sometimes when the pointer is over a link, a wrist movement over the touchpad can open that link.

This may want a separate report, of course. If so, please guide as to the appropriate package. But it seems to be bound up with the screen flicker that is the subject of this bug; and having two sources for mouse-keys must be a source of confusion for the system ...

[Paddy Landau (paddy-landau)]

I have kernel 6.8.0-48, and unfortunately my screen still blanks.

Hardware: Dell OptiPlex 5480 AIO All-In-One with a touchscreen monitor

As reported in bug #2078054 (marked as a duplicate of this one).

[Tushar (rafattushar)]

I am still getting flicking with "Ubuntu 6.8.0-48.48-generic 6.8.12".

Adding "intel_iommu=igfx_off" works for me.

$ lspci -nnk | grep -A3 VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation HD Graphics 630 [8086:591b] (rev 04)
 DeviceName: Onboard IGD
 Subsystem: ASUSTeK Computer Inc. HD Graphics 630 [1043:15e0]
 Kernel driver in use: i915

[AceLan Kao (acelankao)]

I filed a new bug for KBL and CML platforms, please check the test kernel there and help to verify if it works.
Thanks.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2086587

[Bernard Moreton (bernard-moreton-1)]

Please ignore comment 121 above. I don't now think it's related to this issue.
I found the touchpad/mouse problem reported on linuxmint bug 10675 in Feb.2022, and I've added a comment there.

[Paddy Landau (paddy-landau)]

Update for me: I have kernel 6.8.0-48.

Hardware: Dell OptiPlex 5480 AIO All-In-One with a touchscreen monitor.

When I use both "intel_iommu=igfx_off" and "acpi_backlight=native", this solves both this bug and bug #2049248. Without those extras, I continue to have problems.

[Peter Havekes (peter-havekes)]

I had strange horizontal flickering after upgrading to Ubuntu 24.10. The intel_iommu=igfx_off option solved this for me.

❰peter❙~❱✔≻ cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-6.11.0-9-generic root=/dev/mapper/vgubuntu-root ro intel_iommu=igfx_off quiet splash crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M vt.handoff=7

❰peter❙~❱✔≻ uname -a
Linux peter-laptop 6.11.0-9-generic #9-Ubuntu SMP PREEMPT_DYNAMIC Mon Oct 14 13:19:59 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

❰peter❙~❱✔≻ lspci -nnk | grep -A3 VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation Alder Lake-UP3 GT2 [Iris Xe Graphics] [8086:46a8] (rev 0c)
 Subsystem: Dell Device [1028:0b0b]
 Kernel driver in use: i915
 Kernel modules: i915, xe

BIOS Information
 Vendor: Dell Inc.
 Version: 1.26.0
 Release Date: 08/14/2024
System Information
 Manufacturer: Dell Inc.
 Product Name: Latitude 7430
Processor Information
 Socket Designation: U3E1
 Type: Central Processor
 Family: Core i7
 Manufacturer: Intel(R) Corporation

[AceLan Kao (acelankao)]

I don't think ADL is affected by the kernel options, ONFIG_INTEL_IOMMU_DEFAULT_ON and CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON.
It's better that you can file a bug on https://gitlab.freedesktop.org/drm/i915/kernel/-/issues

[Gerhard Burger (burger.ga)]

intel_iommu=igfx_off doesn't fix it for me on my Dell Latitude E5570 with

$ uname -r
6.8.0-49-generic

and

$ lspci -nnk | grep -A3 VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation Skylake GT2 [HD Graphics 520] [8086:1916] (rev 07)
 DeviceName: Onboard IGD
 Subsystem: Dell Skylake GT2 [HD Graphics 520] [1028:06df]
 Kernel driver in use: i915

Is that expected, or how can I debug this further?

[Leonardo Porpora (n0sign4l)]

I am still facing the same issue reported here
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2062951/comments/69

even after updating to 6.8.0-49-generic

[AceLan Kao (acelankao)]

Please try disabe PSR2 if "intel_iommu=igfx_off" doesn't work for you
   i915.enable_psr2_sel_fetch=0

If disable PSR2 works for you, the fix lands at v6.11.
And for v6.8, you may want to report it at bug 2069993

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

This bug is awaiting verification that the linux-gkeop/6.8.0-1002.4 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-noble-linux-gkeop' to 'verification-done-noble-linux-gkeop'. If the problem still exists, change the tag 'verification-needed-noble-linux-gkeop' to 'verification-failed-noble-linux-gkeop'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[R. van der van der Spank (rebbel)]

Can someone explain this question for me? So now we need to test linux-gkeop/6.8.0-1002.4 kernel? I don't know if I need to run it or can run it in Xubuntu 22.04.

I have 6.8.0-49-generic #49~22.04.1-Ubuntu. The problem was fixed for me with "intel_iommu=igfx_off". I thought it was Dell's turn to fix something so that "intel_iommu=igfx_off" is not needed anymore.

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

This bug is awaiting verification that the linux-realtime/6.11.0-1002.2 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-oracular-linux-realtime' to 'verification-done-oracular-linux-realtime'. If the problem still exists, change the tag 'verification-needed-oracular-linux-realtime' to 'verification-failed-oracular-linux-realtime'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

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

This bug is awaiting verification that the linux-gcp-tcpx/6.8.0-1002.3 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy-linux-gcp-tcpx' to 'verification-done-jammy-linux-gcp-tcpx'. If the problem still exists, change the tag 'verification-needed-jammy-linux-gcp-tcpx' to 'verification-failed-jammy-linux-gcp-tcpx'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

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

This bug is awaiting verification that the linux-lowlatency-hwe-6.11/6.11.0-1007.7~24.04.1 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-noble-linux-lowlatency-hwe-6.11' to 'verification-done-noble-linux-lowlatency-hwe-6.11'. If the problem still exists, change the tag 'verification-needed-noble-linux-lowlatency-hwe-6.11' to 'verification-failed-noble-linux-lowlatency-hwe-6.11'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Eugene San (eugenesan)]

OP here.

First, since linux 6.8.0-48 I consider the bug to be fixed at least on the hardware it was reported on.

Second, I see bots adding requests for testing obscure kernel versions with a treat of closing the bug and reverting the fix. I am not sure how to react to this. Can some one with authority chime in on the matter?

Third, linux-hwe 6.11.0-12 is working perfectly as well. Not sure if the fix was ported or it was fixed upstream.

[Gerhard Burger (burger.ga)]

Disabling PSR2 doesn't do anything for me... Also testing 6.11 doesn't do anything to solve the issue. I'm starting to think I may have a separate issue.

Could someone check https://photos.app.goo.gl/at33cQcpw6wrvAqW7 to see if this is a separate problem? Somewhere in the boot process the screen switches to a sort of "interlaced left/right" mode. While using the laptop, the screen is 90% in this interlaced left/right output, and randomly flickers back and forth to the normal output.

[Greg (racer841)]

It certainly does not look like my case, where it happens during x session and the whole screen truns off for some time (like several seconds) and then turns on.

[Paddy Landau (paddy-landau)]

@burger.ga — This looks like a different problem, as far as I can tell. I suggest asking on Ubuntu Discourse for some help to diagnose and fix this.

https://discourse.ubuntu.com/

[Vicente (vicentesloboda)]

I tried to use both kernels in my Latitude 5440:
linux-image-6.8.0-51-generic
linux-image-6.11.0-1010-oem

Both have the flickering problem.

The option intel_iommu=igfx_off make the flickering less often but do not solve the problem.
intel_idle.max_cstate=2 i915.enable_dc=0 make it worse.

lspci
0000:00:00.0 Host bridge: Intel Corporation Raptor Lake-P/U 2p+8e cores Host Bridge/DRAM Controller (rev 01)
0000:00:02.0 VGA compatible controller: Intel Corporation Raptor Lake-P [UHD Graphics] (rev 04)
0000:00:04.0 Signal processing controller: Intel Corporation Raptor Lake Dynamic Platform and Thermal Framework Processor Participant (rev 01)
0000:00:06.0 System peripheral: Intel Corporation RST VMD Managed Controller
0000:00:07.0 PCI bridge: Intel Corporation Raptor Lake-P Thunderbolt 4 PCI Express Root Port #0 (rev 01)
0000:00:07.1 PCI bridge: Intel Corporation Device a73f (rev 01)
0000:00:08.0 System peripheral: Intel Corporation GNA Scoring Accelerator module (rev 01)
0000:00:0a.0 Signal processing controller: Intel Corporation Raptor Lake Crashlog and Telemetry (rev 01)
0000:00:0d.0 USB controller: Intel Corporation Raptor Lake-P Thunderbolt 4 USB Controller (rev 01)
0000:00:0d.2 USB controller: Intel Corporation Raptor Lake-P Thunderbolt 4 NHI #0 (rev 01)
0000:00:0e.0 RAID bus controller: Intel Corporation Volume Management Device NVMe RAID Controller Intel Corporation
0000:00:12.0 Serial controller: Intel Corporation Alder Lake-P Integrated Sensor Hub (rev 01)
0000:00:14.0 USB controller: Intel Corporation Alder Lake PCH USB 3.2 xHCI Host Controller (rev 01)
0000:00:14.2 RAM memory: Intel Corporation Alder Lake PCH Shared SRAM (rev 01)
0000:00:14.3 Network controller: Intel Corporation Raptor Lake PCH CNVi WiFi (rev 01)
0000:00:15.0 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO I2C Controller #0 (rev 01)
0000:00:15.1 Serial bus controller: Intel Corporation Alder Lake PCH Serial IO I2C Controller #1 (rev 01)
0000:00:16.0 Communication controller: Intel Corporation Alder Lake PCH HECI Controller (rev 01)
0000:00:1f.0 ISA bridge: Intel Corporation Raptor Lake LPC/eSPI Controller (rev 01)
0000:00:1f.3 Audio device: Intel Corporation Raptor Lake-P/U/H cAVS (rev 01)
0000:00:1f.4 SMBus: Intel Corporation Alder Lake PCH-P SMBus Host Controller (rev 01)
0000:00:1f.5 Serial bus controller: Intel Corporation Alder Lake-P PCH SPI Controller (rev 01)
0000:00:1f.6 Ethernet controller: Intel Corporation Ethernet Connection (23) I219-LM (rev 01)
10000:e0:06.0 PCI bridge: Intel Corporation Raptor Lake PCIe 4.0 Graphics Port (rev 01)
10000:e1:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller PM9B1 (DRAM-less) (rev 02)

lsmod
Module Size Used by
ccm 20480 6
rfcomm 102400 4
snd_seq_dummy 12288 0
snd_hrtimer 12288 1
qrtr 53248 2
cmac 12288 3
algif_hash 16384 1
algif_skcipher 16384 1
af_alg 32768 6 algif_hash,algif_skcipher
bnep 32768 2
snd_hda_codec_hdmi 98304 1
xe 3141632 0
snd_hda_codec_realtek 212992 1
snd_hd...

[Leo Vleeshouwers (leovleeshouwers)]

I'm experiencing severe flickering when the mouse cursor is in the bottom quarter of the screen. It stops when I move the cursor.

The proposed workarounds do not work for me.
I tried all suggested alterations to grub line GRUB_CMDLINE_LINUX_DEFAULT.
No luck.

Upgrade to 24.04 did not solve the problem.

$ uname -r

6.8.0-49-generic

$ lspci -nnk | grep -A3 VGA

00:02.0 VGA compatible controller [0300]: Intel Corporation CoffeeLake-H GT2 [UHD Graphics 630] [8086:3e9b]
 Subsystem: Acer Incorporated [ALI] CoffeeLake-H GT2 [UHD Graphics 630] [1025:125f]
 Kernel driver in use: i915
 Kernel modules: i915
--
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GP107M [GeForce GTX 1050 Mobile] [10de:1c8d] (rev a1)
 Subsystem: Acer Incorporated [ALI] GP107M [GeForce GTX 1050 Mobile] [1025:1261]
 Kernel driver in use: nvidia
 Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia

[Douglas Gilbert (gilbertdl)]

My suggestion is to try 24.10 and use kernel 6.11. That fixed all my
problems with flicker.

On Fri, Dec 27, 2024, 7:40 AM Leo Vleeshouwers <email address hidden>
wrote:

> I'm experiencing severe flickering when the mouse cursor is in the
> bottom quarter of the screen. It stops when I move the cursor.
>
> The proposed workarounds do not work for me.
> I tried all suggested alterations to grub line GRUB_CMDLINE_LINUX_DEFAULT.
> No luck.
>
> Upgrade to 24.04 did not solve the problem.
>
> $ uname -r
>
> 6.8.0-49-generic
>
> $ lspci -nnk | grep -A3 VGA
>
> 00:02.0 VGA compatible controller [0300]: Intel Corporation CoffeeLake-H
> GT2 [UHD Graphics 630] [8086:3e9b]
> Subsystem: Acer Incorporated [ALI] CoffeeLake-H GT2 [UHD Graphics
> 630] [1025:125f]
> Kernel driver in use: i915
> Kernel modules: i915
> --
> 01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GP107M
> [GeForce GTX 1050 Mobile] [10de:1c8d] (rev a1)
> Subsystem: Acer Incorporated [ALI] GP107M [GeForce GTX 1050
> Mobile] [1025:1261]
> Kernel driver in use: nvidia
> Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia
>
> --
> You received this bug notification because you are subscribed to a
> duplicate bug report (2080588).
> https://bugs.launchpad.net/bugs/2062951
>
> Title:
> Random flickering with Intel i915 (Gen4+ GPUs) on Linux
>
> Status in Linux:
> New
> Status in linux package in Ubuntu:
> Fix Released
> Status in linux-hwe-6.8 package in Ubuntu:
> Confirmed
> Status in linux source package in Jammy:
> Confirmed
> Status in linux-hwe-6.8 source package in Jammy:
> Fix Released
> Status in linux source package in Noble:
> Fix Released
> Status in linux-hwe-6.8 source package in Noble:
> Confirmed
> Status in linux source package in Oracular:
> Fix Released
> Status in linux-hwe-6.8 source package in Oracular:
> Confirmed
>
> Bug description:
> SRU Justification
>
> [Impact]
> The flickering predominantly occurs when the mouse cursor is in the
> bottom quarter of the screen and stops when the cursor leaves this area.
> Extensive testing across various kernel versions revealed that the issue
> became apparent from kernel version 6.8.0 onward, correlating with the
> mentioned configuration changes, CONFIG_INTEL_IOMMU_DEFAULT_ON and
> CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON.
> The problem persists in the latest drm tip.
>
> [Fix]
> As an immediate workaround, adding 'intel_iommu=igfx_off' to the kernel
> command line has been found to effectively eliminate the flickering issue.
> This patch proposes the same behavior as 'intel_iommu=igfx_off' and
> apply the rule to all Intel SKL GPU IDs.
>
> [Test]
> 1. Boot up to desktop with 6.8.0-x kernels
> 2. Moving cursor around the desktop
> 3. There should be no flicker while cursor is moving
>
> [Where problems could occur]
> For virtualized environments using hardware-assisted virtualization for
> graphics (such as VFIO or mediated pass-through), disabling IOMMU for
> graphics could either disable these features or reduce their security and
> efficiency.
> Usually, users pass the 'intel_iommu=on' by themselves when ...

[Leo Vleeshouwers (leovleeshouwers)]

Thank you Douglas Gilbert, I welcome the news that there is a fix in kernel 6.11. Still, I prefer using a LTS release. I am eagerly waiting until Ubuntu 24.04 LTS will get a kernel that solves this annoying long term bug.

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

This bug is awaiting verification that the linux-realtime-6.11/6.11.0-1003.3~24.04.2 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-noble-linux-realtime-6.11' to 'verification-done-noble-linux-realtime-6.11'. If the problem still exists, change the tag 'verification-needed-noble-linux-realtime-6.11' to 'verification-failed-noble-linux-realtime-6.11'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Leo Vleeshouwers (leovleeshouwers)]

I would like to assist.
However, if you really want me to test the new kernel, I need more detailed instruction.
I gave it a try, but my update manager crashed several times.
As yet, I leave testing the new kernel to the Ubuntu experts.

[Curtis Gedak (gedakc)]

I also experience flickering/glitches with my Intel i7-10700k.

```
$ lspci -nnk | grep -A3 VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation CometLake-S GT2 [UHD Graphics 630] [8086:9bc5] (rev 05)
        DeviceName: Onboard - Video
        Subsystem: ASUSTeK Computer Inc. CometLake-S GT2 [UHD Graphics 630] [1043:8694]
        Kernel driver in use: i915
```

In my case I often see a glitchy horizontal line about a quarter of the way down from the top of the monitor screen. It is most prevalent when I use the mouse to drag a window through this region.

This system was upgraded through successive Kubuntu LTS versions until finally arriving at Kubuntu 24.04.1.

I tried the various changes to /etc/default/grub including `intel_iommu=igfx_off` and the flickering remained.

Interestingly if I boot from a USB flash drive with the kubuntu-24.04.1-desktop-amd64.iso image then I do not experience any flickering.

Following are some differences in packages that I noticed that may or may not be relevant to the problem.

Output from `uname -a` on USB flash drive (upper) and on (lower)
----------------------------------------------------------------

Linux kubuntu 6.8.0-41-generic #41-Ubuntu SMP PREEMPT_DYNAMIC Fri Aug 2 20:41:06 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

Linux kaby 6.8.0-51-generic #52-Ubuntu SMP PREEMPT_DYNAMIC Thu Dec 5 13:09:44 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

Output from ` dpkg -l | grep -i intel | grep -vi intelligent`
-------------------------------------------------------------

on USB flash drive (no flickering)
----------------------------------
```
ii firmware-sof-signed 2023.12.1-1ubuntu1 all Intel SOF firmware - signed
ii i965-va-driver:amd64 2.4.1+dfsg1-1build2 amd64 VAAPI driver for Intel G45 & HD Graphics family
ii intel-media-va-driver:amd64 24.1.0+dfsg1-1 amd64 VAAPI driver for the Intel GEN8+ Graphics family
ii intel-microcode 3.20240813.0ubuntu0.24.04.2 amd64 Processor microcode firmware for Intel CPUs
ii iucode-tool 2.3.1-3build1 amd64 Intel processor microcode tool
ii libdrm-intel1:amd64 2.4.120-2build1 amd64 Userspace interface to intel-specific kernel DRM services -- runtime
ii libigdgmm12:amd64 22.3.17+ds1-1 amd64 Intel Graphics Memory Management Library -- shared library
ii libipt2 2.0.6-1build1 amd64 Intel Processor Trace Decoder Library
ii xserver-xorg-video-intel 2:2.99.917+git20210115-1build1 amd64 X.Org X server -- Intel i8xx, i9xx display driver
```

on SSD (yes flickering)
-----------------------
```
ii firmware-sof-signed ...

[Bozsoki András (bozsokiandras)]

Hi!

I am using Ubuntu 22.04.5 LTS now.
If I upgrade to 24.04.2 LTS (6.11 kernel version) will it work without a workaround?
(Lenovo T480, 00:02.0 VGA compatible controller: Intel Corporation UHD Graphics 620 (rev 07))

[Eugene San (eugenesan)]

@bozsokiandras

This bug was originally reported for older Intel HD 5xx graphics and was fixed some time ago in both 6.8 and 6.11 branches.

Judging by the reports above, some owners of Intel UHD 6xx are still reporting issues. I am not sure if the issue they are having is related but If your machine utilizes UHD 6xx, I'd test with LiveCD or install "hwe-edge" kernel" before the upgrade.

[Leo Vleeshouwers (leovleeshouwers)]

I'm using 24.04 LTS.
Upgrade to 6.11.0-17-generic did not resolve the flickering screen.
It still occurs when my mouse cursor is in the lower part of the screen.

[Curtis Gedak (gedakc)]

I still experience screen tearing / glitching after upgrading my computer with intel UHD 630 graphics from Kubuntu 22.04 to 24.04.

However, if I perform a fresh install of Kubuntu 24.04 (in a separate partition) there are no screen display issues.

I wonder what the difference is?

Ideally I would like to fix the upgraded installation as it would be much less work than setting everything up from scratch and restoring data from backup.

[Curtis Gedak (gedakc)]

Possible Workaround for intel UHD 6xx graphics: Switch to Wayland from X11

When I compared package listings between my screen tearing / glitching kubuntu 24.04 upgrade to my smooth display kubuntu 24.04 fresh scratch install I noticed that the latter had additional wayland packages.

This gave me the idea to try wayland. It turns out that this appears to have fixed the issue for me.

Steps to use wayland:

1. Install plasma-workspace-wayland

    sudo apt-get update
    sudo apt-get install plasma-workspace-wayland

2. Logout

3. On user login screen switch session type to wayland (it should be located in the left bottom corner)

4. Login your user

5. To verify wayland session use one approach:
   - Open 'About this System' in 'System Settings' and check 'Graphics Platform' value.
   - Execute `echo $XDG_SESSION_TYPE` in the command line.

Credit for these above steps comes from:

https://dirask.com/snippets/Kubuntu-24-04-enable-wayland-session-1XPME1

Curtis

[Oscar Carlberg (canhasspace)]

I'm on 24.04, latest HWE & latest firmare installed. Still flickers unfortunately

$ lspci -nnk | grep -A3 VGA
00:02.0 VGA compatible controller [0300]: Intel Corporation WhiskeyLake-U GT2 [UHD Graphics 620] [8086:3ea0] (rev 02)
 DeviceName: Onboard - Video
 Subsystem: Dell WhiskeyLake-U GT2 [UHD Graphics 620] [1028:08e1]
 Kernel driver in use: i915

$ uname -r
6.11.0-17-generic