CVE-2026-68454 KVM: s390: pci: Fix handling of AIF enable without AISB

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: Fix handling of AIF enable without AISB When a guest seeks to register IRQs without a summary bit specified, ensure that the associated GAITE then stores 0 for the guest AISB location instead of...