libvmi.txt

    vmi_read()

    => [VMI_TM_KERNEL_SYMBOL] vmi_translate_ksym2v()
    => vmi_pagetable_lookup_cache()
       // dtb = vmi->kpgd if pid == 0
       //     = vmi_pid_to_dtb(vmi, ctx->pid, &dtb) if pid > 0

    => vmi_read_page(vmi, pfn)

    vmi_pagetable_lookup_cache() 
    => vmi->arch_interface->v2p() // v2p_ia32e() in libvmi/arch/amd64.c
       // v2p_ia32e()
          // read and resolute page table. access physical memory by: vmi_read_64_pa()

    vmi_read_page()
    => driver_read_page() => vmi->driver.read_page_ptr(vmi, page) 
    // kvm_read_page() in libvmi/driver/kvm/kvm.c

    kvm_read_page() => memory_cache_insert() => create_new_entry() => vmi->get_data_callback()
    // 3 kinds
       // memory_cache_init(vmi, kvm_get_memory_shm_snapshot ...)
       // memory_cache_init(vmi, kvm_get_memory_patch ... )
       // memory_cache_init(vmi, kvm_get_memory_native ... )

    kvm_get_memory_native() use QEMU QMP xp command: https://en.wikibooks.org/wiki/QEMU/Monitor#xp
    kvm_get_memory_patch() connect socket: kvm_get_instance(vmi)->socket_fd and send request