CVE-2026-64555

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

KVM: arm64: nv: Fix SPSR_EL2 restore in kvm_hyp_handle_mops()

kvm_hyp_handle_mops() resets the single-step state machine as part of

rewinding state for a MOPS exception by modifying vcpu_cpsr() and

writing the result directly into hardware.

In the case of nested virtualization, vcpu_cpsr() is a synthetic value

such that the rest of KVM can deal with vEL2 cleanly. That means the

value requires translation before being written into hardware, which is

unfortunately missing from the MOPS handler.

Fix it by directly modifying SPSR_EL2 and avoiding the synthetic state

altogether, which will be resynchronized on the next 'full' exit back

to KVM.