Random flickering with Intel i915 (Gen9 GPUs) on Linux 6.8 (Ubuntu 24.04)

[Eugene San]

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)]

It's an regression in i915 driver, and I can't find a machine here in our lab to reproduce this issue.

I can teach you how to bisect the kernel to identify the problematic commit, but it's time-consuming. Alternatively, you can file a bug report for Intel using the link below.
https://gitlab.freedesktop.org/drm/i915/kernel/-/issues

[Eugene San (eugenesan)]

@acelankao

Reported upstream: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11504

[kjur (kjur)]

It affects me as well.

I have Intel(R) UHD Graphics (CML GT2) and using i915 driver.

Added below lines to grub:
i915.enable_dc=0 intel_idle.max_cstate=2

No luck.
Then changed it to:
i915.enable_dc=0 intel_idle.max_cstate=4
as per some suggestions

Also no luck.

I experienced the issue a few years back. Can't remember the Ubuntu version then. After adding above lines it was OK. Then after a kernel update it was all fine even without adding the above lines.

Now, after upgrading to 24.04 the problem came back.

It happens randomly for a coupe of seconds every an hour or so.

[Sander Jonkers (jonkers)]

Me too. I did the things below. I'll now test if the flicerking is gone.

Interesting quote above: "running on battery also seems to worsen the problem slightly.". I normally use my laptop on power, but on battery for the past days. So that might be reason I only noticed it now.

sander@witje:~$ lsmod | grep -e ^i915
i915 4276224 17

sander@witje:~$ sudo nano /etc/default/grub

sander@witje:~$ cat /etc/default/grub | grep i915
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash i915.enable_dc=0 intel_idle.max_cstate=2"

sander@witje:~$ sudo update-grub
Sourcing file `/etc/default/grub'
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-6.8.0-38-generic
Found initrd image: /boot/initrd.img-6.8.0-38-generic
Found linux image: /boot/vmlinuz-6.8.0-36-generic
Found initrd image: /boot/initrd.img-6.8.0-36-generic
Found memtest86+ 64bit EFI image: /boot/memtest86+x64.efi
Warning: os-prober will not be executed to detect other bootable partitions.
Systems on them will not be added to the GRUB boot configuration.
Check GRUB_DISABLE_OS_PROBER documentation entry.
Adding boot menu entry for UEFI Firmware Settings ...
done

[IgorHb (xcig)]

I have this issue on integrated Intel UHD Graphics 620. Usually when mouse pointer is on the bottom of the screen, either side. It's very random and hard to reproduce but I could try to record with a different device.

[linuxien_ref (untruclong-durabombarder)]

Same issue

Linux cxxxxxl 6.8.0-38-generic #38-Ubuntu SMP PREEMPT_DYNAMIC Fri Jun 7 15:25:01 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

Gnome 46 Wayland

HP EliteBook 850 G3
Intel Core i5-6300U
Intel HD Graphic 520 (SKL GT2)

[cypherscouter (cypherscouter)]

had a similar issue here https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2062950

[Jeffrey Knockel (jeff250)]

Despite some of the nondeterminism behind this bug, I believe I have bisected this bug to the following commit in the Ubuntu kernel tree: 14ebfcacaeb07b02235f2ea881fd6e34e3de0d6f (edit: I meant to refer to the corresponding commit in the noble kernel: 77e530c1a864c601b96622db03bc1f38e51155f1 ).

More info is available on this commit here: https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/unstable/commit/?id=14ebfcacaeb07b02235f2ea881fd6e34e3de0d6f (edit: I meant to link to the corresponding commit in the noble kernel: https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/noble/commit/?id=77e530c1a864c601b96622db03bc1f38e51155f1 )

The commit text reads:

> UBUNTU: [Config] enable Intel DMA remapping by default
> BugLink: https://bugs.launchpad.net/bugs/1951440
>
> We have tried in the past to enable CONFIG_INTEL_IOMMU_DEFAULT_ON and
> CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON (starting with Jammy), but
> there were multiple issues (especially with old hardware), so we ended
> up disabling these options afterwards, see LP: #1971699.
>
> Considering that IOMMU is enabled by default in upstream kernels,
> probably most of these issues are solved now (or old hardware has been
> decommissioned).
>
> Moreover, having this enabled by default can prevent potential issues
> with modern hardware and drivers (see for example LP #1958004).
>
> Acked-by: Philip Cox <email address hidden>
> Acked-by: Andrei Gherzan <email address hidden>
> Signed-off-by: Andrea Righi <email address hidden>

The commit text even predicts that the commit may introduce problems with older hardware. Its predictions appear unfortunately accurate.

Operating under the assumption that this commit introduced the bug, as a workaround, I have found that adding:

intel_iommu=igfx_off

to the GRUB_CMDLINE appears to resolve the issue for me.

Unfortunately, there appears to be no relief in the newest kernels. I tried the latest daily build available here: https://kernel.ubuntu.com/mainline/daily/

...and found that the issue still persists there with the default GRUB_CMDLINE.

[Claus7 (lastexile7gr)]

Hello,

upgraded from ubuntu 23.10 to 24.04, when at the first time I saw flickering.

some attempts:
1) sudo gedit /etc/modprobe.d/i915.conf
options i915 enable_psr=1 (0 value was what I found there)

2) sudo gedit /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="intel_pstate=guided quiet splash options i915 enable_psr=0"

this resulted in unknown parameter:
3) sudo gedit /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="intel_pstate=guided quiet splash options i915.enable_rc6"

this is what (it seems up to now that) worked:
4) sudo gedit /etc/default/grub
GRUB_CMDLINE_LINUX_DEFAULT="intel_pstate=guided quiet splash intel_idle.max_cstate=1"

for attempts 2-4 grub was updated and then rebooted.

Regards!

specs:
## Hardware Information:
- **Processor:** Intel® Core™ i5-7200U × 4
- **Graphics:** Intel® HD Graphics 620 (KBL GT2)

## Software Information:
- **OS Name:** Ubuntu 24.04 LTS
- **Windowing System:** Wayland
- **Kernel Version:** Linux 6.8.0-39-generic

[Eugene San (eugenesan)]

@jeff250

Thank you for doing your research into the issue but I am confused by your results.

Are you claiming that removing mentioned Ubuntu specific commit resolves the issue?

What about the fact that the issue also affect upstream/mainline kernels?

Are you trying to say that the issue is just related to the conditions described in the commit and intel_iommu=igfx_off?

[Jeffrey Knockel (jeff250)]

> Thank you for doing your research into the issue but I am confused by
> your results.
>
> Are you claiming that removing mentioned Ubuntu specific commit resolves
> the issue?

Specifically it's the first commit where I experience the bug, so I would assume that reverting it will resolve the issue. The commit enables the following compile time kernel config options:

CONFIG_INTEL_IOMMU_DEFAULT_ON=y
CONFIG_INTEL_IOMMU_SCALABLE_MODE_DEFAULT_ON=y

These enable the Intel IOMMU by default (although it can still be disabled by the linux command line at runtime via Grub).

For completeness here is the corresponding commit in the noble kernel:

https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/noble/commit/?id=77e530c1a864c601b96622db03bc1f38e51155f1

> What about the fact that the issue also affect upstream/mainline
> kernels?

I don't know how the kernel config values for the mainline builds that I linked to were derived, but in the build that I tried (built July 25 2024) the above config options were also enabled. I don't know if this is because the upstream kernel has now enabled these config options by default or if the builds that I linked to still use custom Ubuntu config options.

> Are you trying to say that the issue is just related to the conditions
> described in the commit and intel_iommu=igfx_off?

Specifying intel_iommu= on the linux command line is a way of overriding at runtime whatever is specified by the CONFIG_INTEL_IOMMU_DEFAULT_ON config option when the kernel is compiled.

Specifying intel_iommu=off would be the way to completely undo the config changed by the problematic commit, but since the bug that we are experiencing only (to my knowledge) affects graphics, I figured that intel_iommu=igfx_off would be more conservative workaround, as it only disables Intel's integrated graphics from going through the IOMMU but otherwise keeps the IOMMU enabled.

It's not exactly clear to me what the benefits of having graphics going through the Intel IOMMU are, but if Intel's IOMMU was only enabled recently in Ubuntu kernels then I just assume that I won't miss whatever those benefits are.

[Rapha (raphha2)]

@jeff250 you nailed it - thank you for finding that. No more problems on my computer (Intel® Core™ i5 CPU M 560 with Intel Core Processor Integrated Graphics Controller i915, Thinkpad T410)

According to [this section](https://www.kernel.org/doc/html/v6.8/arch/x86/iommu.html?highlight=intel_iommu#graphics-problems), a bug report should be filed. I wonder if this bug report is enough or another one is needed?

[Oibaf (oibaf)]

@Rapha
there was already one, it's also linked here now.

[arnoldthebat (tony-ditchfield)]

@jeff250 - can confirm this has fixed it for me as well

intel_iommu=igfx_off

Huge thanks!

[Eugene San (eugenesan)]

Update:
Thanks to @jeff250 it seems like we narrowed the issue to kernel config changes between 6.6 and 6.8 in Ubuntu kernels.

Unfortunately, proper fix is still not available but we have a working workaround (intel_iommu=igfx_off).

More details can be found at upstream bug report: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/11504

[AceLan Kao (acelankao)]

This kernel added the SKL ID to the quirk which did the same thing as intel_iommu=igfx_off
We may have to carry these quirks before Intel provides a real fix.
Please give it a try and I'll submit SRU later.

https://people.canonical.com/~acelan/bugs/lp2062951/

[Eugene San (eugenesan)]

@acelankao
The patched kernel (without any parameters) seems to be working without any issues.