With shadow paging enabled, the INVPCID instruction results in a call to kvm_mmu_invpcid_gva. If INVPCID is executed with CR0.PG=0, the invlpg callback is not set and the result is a NULL pointer dereference.
https://www.debian.org/security/2022/dsa-5161
https://kb.cert.org/vuls/id/647177/