A user has reported extensive performance issues with a Lenovo Thinkpad X1 Extreme Gen 2 laptop computer, in bug 1973434. The user reports video playback hangs, browser hangs and virtual machines hanging.
Their dmesg indicates the system has 2x IOMMUs and there are 25 groups being configured. They tested "intel_iommu=off", and the performance issues are no longer seen. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1971699 Title: disable Intel DMA remapping by default Status in linux package in Ubuntu: Invalid Status in linux source package in Jammy: In Progress Bug description: [Impact] It seems that enabling Intel IOMMU can cause some weird gfx problems, see for example: https://bugs.launchpad.net/bugs/1971146 https://bugs.launchpad.net/bugs/1965882 [Test case] We don't have any specific test case, only other bug reports that tracked down the origin of the issue as being introduced when CONFIG_INTEL_IOMMU_DEFAULT_ON has been enabled by default. [Fix] Revert "UBUNTU: [Config] enable Intel DMA remapping options by default" [Regression potential] DMA remapping device not present at boot by default, users that require this feature will need to specifically add intel_iommu=on to the kernel boot parameters to enable it. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1971699/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp