Important: kernel security update (Oracle Linux 8)

[4.18.0-553.147.1]
- Update Oracle Linux certificates (Kevin Lyons)
- Disable signing for aarch64 (Ilya Okomin)
- Oracle Linux RHCK Module Signing Key was added to the kernel trusted keys list (olkmod_signing_key.pem) [Orabug: 29539237]
- Update x509.genkey [Orabug: 24817676]
- Conflict with shim-ia32 and shim-x64 <= 15.3-1.0.3
- Remove upstream reference during boot (Kevin Lyons) [Orabug: 34750652]
- Add new Oracle Linux Driver Signing (key 1) certificate [Orabug: 37985772]

[4.18.0-553.147.1]
- KVM: x86/mmu: Ensure hugepage is in by slot before checking max mapping level (Aidan Wallace) [RHEL-213341] {CVE-2026-63807}
- KVM: nVMX: Hide shadow VMCS right after VMCLEAR (Aidan Wallace) [RHEL-213341]
- KVM: x86: Check for invalid/obsolete root *after* making MMU pages available (Aidan Wallace) [RHEL-213341]
- KVM: nVMX: Put vmcs12 pages if nested VM-Enter fails due to invalid guest state (Aidan Wallace) [RHEL-213341]
- KVM: nVMX: Add helper to put (unmap) vmcs12 pages (Aidan Wallace) [RHEL-213341]
- KVM: nVMX: Use kvm_vcpu_map() to get/pin vmcs12's APIC-access page (Aidan Wallace) [RHEL-213341]
- KVM: x86: Don't (re)check L1 intercepts when completing userspace I/O (Aidan Wallace) [RHEL-211228] {CVE-2025-40026}
- KVM: x86: wean in-kernel PIO from vcpu->arch.pio* (Aidan Wallace) [RHEL-211228]
- KVM: x86: move all vcpu->arch.pio* setup in emulator_pio_in_out() (Aidan Wallace) [RHEL-211228]
- KVM: x86: drop PIO from unregistered devices (Aidan Wallace) [RHEL-211228]
- KVM: x86: inline kernel_pio into its sole caller (Aidan Wallace) [RHEL-211228]
- serial: 8250_mid: Disable DMA for selected platforms (Mark Salter) [RHEL-190191]
- tipc: fix double-free in tipc_buf_append() (CKI Backport Bot) [RHEL-192178] {CVE-2026-52993}
- xfrm: esp: restore combined single-frag length gate (CKI Backport Bot) [RHEL-178324]
- dm log: fix out-of-bounds write due to region_count overflow (CKI Backport Bot) [RHEL-188543] {CVE-2026-53059}
- xfs: Use xarray to track SB UUIDs instead of plain array. (Lukas Herbolt) [RHEL-127174]
- selftests: kvm: try getting XFD and XSAVE state out of sync (Paolo Bonzini) [RHEL-166738]
- selftests: kvm: replace numbering of sync points with actions (Paolo Bonzini) [RHEL-166738]
- x86/fpu: Clear XSTATE_BV[i] in guest XSAVE state whenever XFD[i]=1 (Paolo Bonzini) [RHEL-166738]
- mount: Retest MNT_LOCKED in do_umount (Ian Kent) [RHEL-152655]
- mount: Don't allow copying MNT_UNBINDABLE|MNT_LOCKED mounts (Ian Kent) [RHEL-152655]
- mount: Prevent MNT_DETACH from disconnecting locked mounts (Ian Kent) [RHEL-152655]