A patch was submitted to the Ubuntu kernel team mailing list for Oracular: https://lists.ubuntu.com/archives/kernel-team/2025-March/158360.html
An Oracular patched version is available in this PPA for testing: https://launchpad.net/~mpellizzer/+archive/ubuntu/ibm-z/ Changing status to 'In Progress'. ** Changed in: linux (Ubuntu Oracular) Status: Triaged => In Progress -- 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/2104120 Title: [Ubuntu 25.04] s390/pci: Fix PCHID per port multi-function detection Status in Ubuntu on IBM z Systems: Triaged Status in linux package in Ubuntu: Fix Released Status in linux source package in Noble: Fix Committed Status in linux source package in Oracular: In Progress Status in linux source package in Plucky: Fix Released Bug description: [Impact] Description: s390/pci: Fix PCHID per port multi-function detection Symptom: There are two cases in which PCI functions are incorrectly placed, or not placed, in a shared PCI topology. In the first case a PCI physical function (PF) which is initially in standby was incorrectly not creating a new PCI topology when hotplugged, but would if configured during boot. In the second case a PCI virtual function (VF) would be placed in the shared PCI topology of a PF if that PF is from the same card even if the parent PF is not in the configuration which should lead the VF to be isolated in its own single function topology. Problem: Both problems are caused by logic bugs in the determination of which PCI functions create topologies and when a PCI function may be added to an existing topology. [Fix] Cherry pick from mainline of: - dc287e4c9149 s390/pci: Fix SR-IOV for PFs initially in standby - 05793884a1f3 s390/pci: Pull search for parent PF out of pci_iov_setup_virtfn() - 2844ddbd540f s390/pci: Fix handling of isolated VFs [Test Plan] Fix tested by IBM. [Where problems could occur] The fix affects SR-IOV support in the s390x PCI subsystem. A user might experience issues like missing or misconfigured VFs, failed VF passthrough to guests, sysfs inconsistencies, or degraded I/O performance. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/2104120/+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
