![Mukesh Rathor](/assets/img/avatar_default.png)
PVH allows PV linux guest to utilize hardware extended capabilities, such as running MMU updates in a HVM container. The Xen side defines PVH as (from docs/misc/pvh-readme.txt, with modifications): "* the guest uses auto translate: - p2m is managed by Xen - pagetables are owned by the guest - mmu_update hypercall not available * it uses event callback and not vlapic emulation, * IDT is native, so set_trap_table hcall is also N/A for a PVH guest. For a full list of hcalls supported for PVH, see pvh_hypercall64_table in arch/x86/hvm/hvm.c in xen. From the ABI prespective, it's mostly a PV guest with auto translate, although it does use hvm_op for setting callback vector." Use .ascii and .asciz to define xen feature string. Note, the PVH string must be in a single line (not multiple lines with \) to keep the assembler from putting null char after each string before \. This patch allows it to be configured and enabled. We also use introduce the 'XEN_ELFNOTE_SUPPORTED_FEATURES' ELF note to tell the hypervisor that 'hvm_callback_vector' is what the kernel needs. We can not put it in 'XEN_ELFNOTE_FEATURES' as older hypervisor parse fields they don't understand as errors and refuse to load the kernel. This work-around fixes the problem. Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
59 lines
1.4 KiB
Plaintext
59 lines
1.4 KiB
Plaintext
#
|
|
# This Kconfig describes xen options
|
|
#
|
|
|
|
config XEN
|
|
bool "Xen guest support"
|
|
depends on PARAVIRT
|
|
select PARAVIRT_CLOCK
|
|
select XEN_HAVE_PVMMU
|
|
depends on X86_64 || (X86_32 && X86_PAE && !X86_VISWS)
|
|
depends on X86_TSC
|
|
help
|
|
This is the Linux Xen port. Enabling this will allow the
|
|
kernel to boot in a paravirtualized environment under the
|
|
Xen hypervisor.
|
|
|
|
config XEN_DOM0
|
|
def_bool y
|
|
depends on XEN && PCI_XEN && SWIOTLB_XEN
|
|
depends on X86_LOCAL_APIC && X86_IO_APIC && ACPI && PCI
|
|
|
|
# Dummy symbol since people have come to rely on the PRIVILEGED_GUEST
|
|
# name in tools.
|
|
config XEN_PRIVILEGED_GUEST
|
|
def_bool XEN_DOM0
|
|
|
|
config XEN_PVHVM
|
|
def_bool y
|
|
depends on XEN && PCI && X86_LOCAL_APIC
|
|
|
|
config XEN_MAX_DOMAIN_MEMORY
|
|
int
|
|
default 500 if X86_64
|
|
default 64 if X86_32
|
|
depends on XEN
|
|
help
|
|
This only affects the sizing of some bss arrays, the unused
|
|
portions of which are freed.
|
|
|
|
config XEN_SAVE_RESTORE
|
|
bool
|
|
depends on XEN
|
|
select HIBERNATE_CALLBACKS
|
|
default y
|
|
|
|
config XEN_DEBUG_FS
|
|
bool "Enable Xen debug and tuning parameters in debugfs"
|
|
depends on XEN && DEBUG_FS
|
|
default n
|
|
help
|
|
Enable statistics output and various tuning options in debugfs.
|
|
Enabling this option may incur a significant performance overhead.
|
|
|
|
config XEN_PVH
|
|
bool "Support for running as a PVH guest"
|
|
depends on X86_64 && XEN
|
|
select XEN_PVHVM
|
|
def_bool n
|