Yesterday I upgraded Ubuntu 22.04 to 24.04.1 and the bug is now gone On Mon, Sep 2, 2024 at 6:51 PM Sütő Norbert <2062...@bugs.launchpad.net> wrote:
> GRUB_CMDLINE_LINUX_DEFAULT="quiet splash intel_iommu=igfx_off" > > > It also fix on my side. > > -- > You received this bug notification because you are subscribed to a > duplicate bug report (2077291). > https://bugs.launchpad.net/bugs/2062951 > > Title: > Random flickering with Intel i915 (Gen9 GPUs) on Linux 6.8 (Ubuntu > 24.04) > > Status in Linux: > New > Status in linux package in Ubuntu: > In Progress > Status in linux-hwe-6.8 package in Ubuntu: > Invalid > Status in linux source package in Jammy: > Invalid > Status in linux-hwe-6.8 source package in Jammy: > Confirmed > Status in linux source package in Noble: > Fix Committed > Status in linux-hwe-6.8 source package in Noble: > Invalid > Status in linux source package in Oracular: > In Progress > Status in linux-hwe-6.8 source package in Oracular: > Invalid > > 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 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 > > To manage notifications about this bug go to: > https://bugs.launchpad.net/linux/+bug/2062951/+subscriptions > > -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2062951 Title: Random flickering with Intel i915 (Gen9 GPUs) on Linux 6.8 (Ubuntu 24.04) To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/2062951/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs