Random flickering with Intel i915 (Comet Lake and Kaby Lake) on Linux 6.8+

[AceLan Kao]

[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 KBL and CML GPU IDs.

[Test]
1. Boot up to desktop with ubuntu kernels(6.8+)
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.

[AceLan Kao (acelankao)]

Here is the test kernel and patch.
https://people.canonical.com/~acelan/bugs/lp2086587

[Jeffrey Knockel (jeff250)]

Thanks, before testing I disabled the intel_iommu= workaround, and this kernel does indeed fix the flicker issue for me.

For reference this is my hardware:

$ 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

The 6.8.0-48 kernel had not fixed the flicker issue for me, but this one does.

[Tushar (rafattushar)]

Thank you for this test kernel and patch.

I'll use and test it for some days and let you know the results.

$ 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

[Tushar (rafattushar)]

I've been using this kernel for three days. This kernel fixes my flicker issue without adding "intel_iommu=igfx_off".

$ 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

Previously, adding "intel_iommu=igfx_off" worked for me. "Ubuntu 6.8.0-48.48-generic 6.8.12" didn't solve my issue.

[Tushar (rafattushar)]

After using 10 days I can confirm that this kernel fixes my flicking issue.

$ 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

$ uname -a
Linux ubuntu-2404 6.8.0-2048-generic #48 SMP PREEMPT_DYNAMIC Mon Nov 4 02:13:02 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux

$ cat /proc/version_signature
Ubuntu 6.8.0-2048.48-generic 6.8.12

$ cat /proc/cmdline
BOOT_IMAGE=/boot/vmlinuz-6.8.0-2048-generic root=UUID=d2f7fa92-eef1-45e1-bc25-1c71605c7f42 ro quiet splash vt.handoff=7

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

This bug is awaiting verification that the linux/6.11.0-17.17 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' to 'verification-done-oracular-linux'. If the problem still exists, change the tag 'verification-needed-oracular-linux' to 'verification-failed-oracular-linux'.

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/6.8.0-53.55 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' to 'verification-done-noble-linux'. If the problem still exists, change the tag 'verification-needed-noble-linux' to 'verification-failed-noble-linux'.

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!

[Jeffrey Knockel (jeff250)]

Looks good! Using 6.8.0-51, I disabled the `intel_iommu=igfx_off` workaround and reproduced the flicker. I then installed 6.8.0-53 from noble-proposed and failed to reproduce the flicker, even though the `intel_iommu=igfx_off` workaround was still disabled.

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 6.12.0-12.12

---------------
linux (6.12.0-12.12) plucky; urgency=medium

  * plucky/linux: 6.12.0-12.12 -proposed tracker (LP: #2095505)

  * Miscellaneous Ubuntu changes
    - [Packaging] temporarily disable signing for s390x

  * Miscellaneous upstream changes
    - modpost: remove unnecessary check in do_acpi_entry()
    - modpost: introduce module_alias_printf() helper
    - modpost: pass (struct module *) to do_*_entry() functions
    - modpost: call module_alias_printf() from all do_*_entry() functions
    - modpost: fix the missed iteration for the max bit in do_input()
    - modpost: work around unaligned data access error

 -- Paolo Pisati <email address hidden> Wed, 22 Jan 2025 15:27:46 +0100

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

This bug is awaiting verification that the linux-intel/6.11.0-1007.7 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-intel' to 'verification-done-oracular-linux-intel'. If the problem still exists, change the tag 'verification-needed-oracular-linux-intel' to 'verification-failed-oracular-linux-intel'.

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!

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 6.8.0-53.55

---------------
linux (6.8.0-53.55) noble; urgency=medium

  * noble/linux: 6.8.0-53.55 -proposed tracker (LP: #2093677)

  * Packaging resync (LP: #1786013)
    - [Packaging] debian.master/dkms-versions -- update from kernel-versions
      (main/2025.01.13)

  * generate and ship vmlinux.h to allow packages to build BPF CO-RE
    (LP: #2050083)
    - [Packaging] add linux-bpf-dev package
    - [Packaging] do not attempt to generate BTF header on armhf

  * Unable to boot as a guest on VMware ESX (LP: #2091941)
    - ptp/vmware: Use VMware hypercall API
    - input/vmmouse: Use VMware hypercall API
    - drm/vmwgfx: Use VMware hypercall API
    - x86/vmware: Use VMware hypercall API
    - x86/vmware: Correct macro names
    - x86/vmware: Remove legacy VMWARE_HYPERCALL* macros

  * When /dev/vmbus/hv_kvp is not present, disable hv-kvp-daemon (LP: #2091744)
    - [Packaging] disable hv-kvp-daemon if needed

  * Backport "netkit: Add option for scrubbing skb meta data" to 6.8
    (LP: #2091184)
    - netkit: Add option for scrubbing skb meta data

  * KVM: Cache CPUID at KVM.ko module init to reduce latency of VM-Enter and VM-
    Exit (LP: #2093146)
    - KVM: x86: Cache CPUID.0xD XSTATE offsets+sizes during module init

  * [SRU] add support of QCA BT 0489:e0fc (LP: #2085406)
    - Bluetooth: btusb: add Foxconn 0xe0fc for Qualcomm WCN785x

  * ice driver RTNL assertion failed warning on shutdown/reboot (LP: #2091107)
    - ice: Remove and readd netdev during devlink reload

  * vfio_pci soft lockup on VM start while using PCIe passthrough (LP: #2089306)
    - SAUCE: Revert "vfio/pci: Insert full vma on mmap'd MMIO fault"
    - SAUCE: Revert "vfio/pci: Use unmap_mapping_range()"

  * [SRU] Fix error of resume on rtl8168fp (LP: #2087507)
    - r8169: avoid unsolicited interrupts

  * [SRU] power: intel_pstate: HWP interrupt support for maximum ratio changed
    (LP: #2090852)
    - x86/cpufeatures: Add HWP highest perf change feature flag
    - cpufreq: intel_pstate: Support highest performance change interrupt

  * Noble update: upstream stable patchset 2024-11-29 (LP: #2089884)
    - static_call: Handle module init failure correctly in
      static_call_del_module()
    - static_call: Replace pointless WARN_ON() in static_call_module_notify()
    - jump_label: Simplify and clarify static_key_fast_inc_cpus_locked()
    - jump_label: Fix static_key_slow_dec() yet again
    - scsi: st: Fix input/output error on empty drive reset
    - scsi: pm8001: Do not overwrite PCI queue mapping
    - drm/amdgpu: Fix get each xcp macro
    - mailbox: rockchip: fix a typo in module autoloading
    - mailbox: bcm2835: Fix timeout during suspend mode
    - ceph: remove the incorrect Fw reference check when dirtying pages
    - ieee802154: Fix build error
    - net: sparx5: Fix invalid timestamps
    - net/mlx5: Fix error path in multi-packet WQE transmit
    - net/mlx5: Added cond_resched() to crdump collection
    - net/mlx5e: Fix NULL deref in mlx5e_tir_builder_alloc()
    - net/mlx5e: Fix crash caused by calling __xfrm_state_delete() twice
    - netfilter: uapi: NFTA_FLOWTABLE_HOOK is NLA_NESTED
    - net...

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 6.11.0-18.18

---------------
linux (6.11.0-18.18) oracular; urgency=medium

  * CVE-2025-0927
    - SAUCE: fs: hfs/hfsplus: add key_len boundary check to hfs_bnode_read_key

linux (6.11.0-17.17) oracular; urgency=medium

  * oracular/linux: 6.11.0-17.17 -proposed tracker (LP: #2093643)

  * Packaging resync (LP: #1786013)
    - [Packaging] debian.master/dkms-versions -- update from kernel-versions
      (main/2025.01.13)

  * When /dev/vmbus/hv_kvp is not present, disable hv-kvp-daemon (LP: #2091744)
    - [Packaging] disable hv-kvp-daemon if needed

  * Backport "netkit: Add option for scrubbing skb meta data" to 6.8
    (LP: #2091184)
    - netkit: Add option for scrubbing skb meta data

  * KVM: Cache CPUID at KVM.ko module init to reduce latency of VM-Enter and VM-
    Exit (LP: #2093146)
    - KVM: x86: Cache CPUID.0xD XSTATE offsets+sizes during module init

  * [SRU] add support of QCA BT 0489:e0fc (LP: #2085406)
    - Bluetooth: btusb: add Foxconn 0xe0fc for Qualcomm WCN785x

  * oracular: ubuntu_boot lib/dynamic_queue_limits.c:99! (LP: #2089684)
    - virtio_net: correct netdev_tx_reset_queue() invocation point
    - virtio_ring: add a func argument 'recycle_done' to virtqueue_resize()
    - virtio_net: ensure netdev_tx_reset_queue is called on tx ring resize

  * Failed to probe for OVTI02C1: chip id mismatch: 560243!=0 (LP: #2090932)
    - SAUCE: ACPI: scan: Update HID for new platform

  * Bluetooth[8086:a876] crash with "hci0: Failed to read MSFT supported
    features (-110)" (LP: #2085485)
    - Bluetooth: btintel_pcie: Add recovery mechanism

  * Poor bluetooth performance on Lenovo X13s (LP: #2089357)
    - SAUCE: Bluetooth: qca: Support downloading board ID specific NVM for WCN6855

  * vfio_pci soft lockup on VM start while using PCIe passthrough (LP: #2089306)
    - SAUCE: Revert "mm: use rwsem assertion macros for mmap_lock"
    - SAUCE: Revert "vfio/pci: Insert full vma on mmap'd MMIO fault"
    - SAUCE: Revert "vfio/pci: Use unmap_mapping_range()"

  * Oracular update: v6.11.11 upstream stable release (LP: #2091655)
    - wifi: mac80211: Fix setting txpower with emulate_chanctx
    - wifi: cfg80211: Add wiphy_delayed_work_pending()
    - wifi: mac80211: Convert color collision detection to wiphy work
    - wifi: radiotap: Avoid -Wflex-array-member-not-at-end warnings
    - spi: stm32: fix missing device mode capability in stm32mp25
    - ASoC: codecs: rt5640: Always disable IRQs from rt5640_cancel_work()
    - ASoC: Intel: bytcr_rt5640: Add support for non ACPI instantiated codec
    - ASoC: Intel: bytcr_rt5640: Add DMI quirk for Vexia Edu Atla 10 tablet
    - ASoC: Intel: sst: Support LPE0F28 ACPI HID
    - wifi: iwlwifi: mvm: Use the sync timepoint API in suspend
    - wifi: iwlwifi: mvm: SAR table alignment
    - mac80211: fix user-power when emulating chanctx
    - usb: add support for new USB device ID 0x17EF:0x3098 for the r8152 driver
    - usb: typec: use cleanup facility for 'altmodes_node'
    - selftests/watchdog-test: Fix system accidentally reset after watchdog-test
    - ALSA: hda/realtek: Add subwoofer quirk for Infinix ZERO BOOK 13
    - ASoC: codecs: wcd937x: ...

[Timo Aaltonen (tjaalton)]

The verification of the Stable Release Update for linux has completed successfully and the package is now being released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

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

This bug is awaiting verification that the linux-nvidia-tegra/6.8.0-1003.3 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-noble-linux-nvidia-tegra' to 'verification-done-noble-linux-nvidia-tegra'. If the problem still exists, change the tag 'verification-needed-noble-linux-nvidia-tegra' to 'verification-failed-noble-linux-nvidia-tegra'.

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-nvidia-tegra-pvw/6.8.0-1004.4 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-nvidia-tegra-pvw' to 'verification-done-noble-linux-nvidia-tegra-pvw'. If the problem still exists, change the tag 'verification-needed-noble-linux-nvidia-tegra-pvw' to 'verification-failed-noble-linux-nvidia-tegra-pvw'.

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-6.11/6.11.0-1011.11~24.04.1 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-gcp-6.11' to 'verification-done-noble-linux-gcp-6.11'. If the problem still exists, change the tag 'verification-needed-noble-linux-gcp-6.11' to 'verification-failed-noble-linux-gcp-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!

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

This bug is awaiting verification that the linux-azure/6.8.0-1025.30 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-azure' to 'verification-done-noble-linux-azure'. If the problem still exists, change the tag 'verification-needed-noble-linux-azure' to 'verification-failed-noble-linux-azure'.

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-nvidia-6.11/6.11.0-1004.4 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-nvidia-6.11' to 'verification-done-noble-linux-nvidia-6.11'. If the problem still exists, change the tag 'verification-needed-noble-linux-nvidia-6.11' to 'verification-failed-noble-linux-nvidia-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!

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

This bug is awaiting verification that the linux-azure-6.11/6.11.0-1012.12~24.04.1 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-azure-6.11' to 'verification-done-noble-linux-azure-6.11'. If the problem still exists, change the tag 'verification-needed-noble-linux-azure-6.11' to 'verification-failed-noble-linux-azure-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!

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

This bug is awaiting verification that the linux-azure-nvidia/6.8.0-1014.15 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-azure-nvidia' to 'verification-done-noble-linux-azure-nvidia'. If the problem still exists, change the tag 'verification-needed-noble-linux-azure-nvidia' to 'verification-failed-noble-linux-azure-nvidia'.

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-aws-6.11/6.11.0-1013.14~24.04.1 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-aws-6.11' to 'verification-done-noble-linux-aws-6.11'. If the problem still exists, change the tag 'verification-needed-noble-linux-aws-6.11' to 'verification-failed-noble-linux-aws-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!

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

This bug is awaiting verification that the linux-fips/6.8.0-72.72+fips1 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-fips' to 'verification-done-noble-linux-fips'. If the problem still exists, change the tag 'verification-needed-noble-linux-fips' to 'verification-failed-noble-linux-fips'.

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-aws-fips/6.8.0-1034.36+fips1 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-aws-fips' to 'verification-done-noble-linux-aws-fips'. If the problem still exists, change the tag 'verification-needed-noble-linux-aws-fips' to 'verification-failed-noble-linux-aws-fips'.

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-fips/6.8.0-1035.37+fips1 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-gcp-fips' to 'verification-done-noble-linux-gcp-fips'. If the problem still exists, change the tag 'verification-needed-noble-linux-gcp-fips' to 'verification-failed-noble-linux-gcp-fips'.

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-xilinx/6.8.0-1017.18 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-xilinx' to 'verification-done-noble-linux-xilinx'. If the problem still exists, change the tag 'verification-needed-noble-linux-xilinx' to 'verification-failed-noble-linux-xilinx'.

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-azure-fips/6.8.0-1034.39+fips1 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-azure-fips' to 'verification-done-noble-linux-azure-fips'. If the problem still exists, change the tag 'verification-needed-noble-linux-azure-fips' to 'verification-failed-noble-linux-azure-fips'.

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!

[Daniel Letzeisen (dtl131)]

Just got a report that a user hit this bug on 6.8.0-71 and 6.14.0-27 HWE kernels, and needed to use intel_iommu=igfx_off on Core i5-8265U, WhiskeyLake, 8086:3ea0