This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 1982104 and then change the status of the bug to 'Confirmed'. If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'. This change has been made by an automated script, maintained by the Ubuntu Kernel Team. ** Changed in: linux (Ubuntu) Status: New => Incomplete ** Changed in: linux (Ubuntu Jammy) Status: New => Incomplete -- 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/1982104 Title: Fixes intel_iommu: enable intel_iommu, Ubuntu 22.04 installation crashes Status in linux package in Ubuntu: In Progress Status in linux-oem-5.14 package in Ubuntu: New Status in linux-oem-5.17 package in Ubuntu: New Status in linux source package in Focal: New Status in linux-oem-5.14 source package in Focal: In Progress Status in linux-oem-5.17 source package in Focal: New Status in linux source package in Jammy: In Progress Status in linux-oem-5.14 source package in Jammy: New Status in linux-oem-5.17 source package in Jammy: In Progress Status in linux source package in Kinetic: In Progress Status in linux-oem-5.14 source package in Kinetic: New Status in linux-oem-5.17 source package in Kinetic: New Bug description: [Impact] Ubuntu 22.04 installation crashes on our Intel Sapphire Rapids proto server which is targeting Telco workloads. Attaching the console logs. Currently, it looks like disabling VT-D option in BIOS settings helps mitigate the issue. Console logs indicate something is wrong in iommu/dmar subsystem. [Fix] The IOMMU driver shares the pasid table for PCI alias devices. When the RID2PASID entry of the shared pasid table has been filled by the first device, the subsequent device will encounter the "DMAR: Setup RID2PASID failed" failure as the pasid entry has already been marked as present. As the result, the IOMMU probing process will be aborted. On the contrary, when any alias device is hot-removed from the system, for example, by writing to /sys/bus/pci/devices/.../remove, the shared RID2PASID will be cleared without any notifications to other devices. As the result, any DMAs from those rest devices are blocked. Sharing pasid table among PCI alias devices could save two memory pages for devices underneath the PCIe-to-PCI bridges. Anyway, considering that those devices are rare on modern platforms that support VT-d in scalable mode and the saved memory is negligible, it's reasonable to remove this part of immature code to make the driver feasible and stable. [Test Case] 1. use the target machine(Intel Sapphire Rapids) and install the kernel with the fix. 2. boot the target machine 3. check dmesg if the error message exists [ 8.120527] pci 0000:03:01.0: DMAR: Setup RID2PASID failed [Where problems could occur] After enable intel_iommu, the errors may be occurred. We need to figure out one by one once the related errors are triggered in the future. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1982104/+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