CVE-2026-89795

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

PCI: Allow per function PCI slots to fix slot reset on s390

On s390 systems, which use a machine level hypervisor, PCI devices are

always accessed through a form of PCI pass-through which fundamentally

operates on a per PCI function granularity. This is also reflected in the

s390 PCI hotplug driver which creates hotplug slots for individual PCI

functions. Its reset_slot() function, which is a wrapper for

zpci_hot_reset_device(), thus also resets individual functions.

Currently, the pci_create_slot() assigns the same pci_slot object to

multifunction devices. This approach worked fine on s390 systems that only

exposed virtual functions as individual PCI domains to the operating

system. Since commit 44510d6fa0c0 ("s390/pci: Handling multifunctions")

s390 supports exposing the topology of multifunction PCI devices by

grouping them in a shared PCI domain. This creates a problem when resetting

a function through the hotp

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References