group xen_elfnote_features


The list of all the features the guest supports. They are set by parsing the XEN_ELFNOTE_FEATURES and XEN_ELFNOTE_SUPPORTED_FEATURES string. The format is the feature names (as given here without the “XENFEAT_” prefix) separated by ‘|’ characters. If a feature is required for the kernel to function then the feature name must be preceded by a ‘!’ character.

Note that if XEN_ELFNOTE_SUPPORTED_FEATURES is used, then in the XENFEAT_dom0 MUST be set if the guest is to be booted as dom0.


XENFEAT_writable_page_tables 0

If set, the guest does not need to write-protect its pagetables, and can update them via direct writes.

XENFEAT_writable_descriptor_tables 1

If set, the guest does not need to write-protect its segment descriptor tables, and can update them via direct writes.

XENFEAT_auto_translated_physmap 2

If set, translation between the guest’s ‘pseudo-physical’ address space and the host’s machine address space are handled by the hypervisor. In this mode the guest does not need to perform phys-to/from-machine translations when performing page table operations.

XENFEAT_supervisor_mode_kernel 3

If set, the guest is running in supervisor mode (e.g., x86 ring 0).

XENFEAT_pae_pgdir_above_4gb 4

If set, the guest does not need to allocate x86 PAE page directories below 4GB. This flag is usually implied by auto_translated_physmap.

XENFEAT_mmu_pt_update_preserve_ad 5

x86: Does this Xen host support the MMU_PT_UPDATE_PRESERVE_AD hypercall?

XENFEAT_highmem_assist 6

x86: Does this Xen host support the MMU_{CLEAR,COPY}_PAGE hypercall?

XENFEAT_gnttab_map_avail_bits 7

If set, GNTTABOP_map_grant_ref honors flags to be placed into guest kernel available pte bits.

XENFEAT_hvm_callback_vector 8

x86: Does this Xen host support the HVM callback vector type?

XENFEAT_hvm_safe_pvclock 9

x86: pvclock algorithm is safe to use on HVM

XENFEAT_hvm_pirqs 10

x86: pirq can be used by HVM guests

XENFEAT_dom0 11

operation as Dom0 is supported

XENFEAT_memory_op_vnode_supported 13

Guest can use XENMEMF_vnode to specify virtual node for memory op.

XENFEAT_ARM_SMCCC_supported 14

arm: Hypervisor supports ARM SMC calling convention.

XENFEAT_linux_rsdp_unrestricted 15

x86/PVH: If set, ACPI RSDP can be placed at any address. Otherwise RSDP must be located in lower 1MB, as required by ACPI Specification for IA-PC systems. This feature flag is only consulted if XEN_ELFNOTE_GUEST_OS contains the “linux” string.

XENFEAT_not_direct_mapped 16
XENFEAT_direct_mapped 17