From: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx> Sent: Monday, March 20, 2023 3:04 AM > > Add HYPERV_VTL_MODE Kconfig flag for VTL mode. > > Signed-off-by: Saurabh Sengar <ssengar@xxxxxxxxxxxxxxxxxxx> > --- > arch/x86/Kconfig | 24 ++++++++++++++++++++++++ > arch/x86/hyperv/Makefile | 1 + > 2 files changed, 25 insertions(+) > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 453f462f6c9c..c3faaaea1e31 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -782,6 +782,30 @@ menuconfig HYPERVISOR_GUEST > > if HYPERVISOR_GUEST > > +config HYPERV_VTL_MODE > + bool "Enable Linux to boot in VTL context" > + depends on X86_64 && HYPERV > + default n > + help > + Virtual Secure Mode (VSM) is a set of hypervisor capabilities and > + enlightenments offered to host and guest partitions which enables > + the creation and management of new security boundaries within > + operating system software. > + > + VSM achieves and maintains isolation through Virtual Trust Levels > + (VTLs). Virtual Trust Levels are hierarchical, with higher levels > + being more privileged than lower levels. VTL0 is the least privileged > + level, and currently only other level supported is VTL2. > + > + Select this option to build a Linux kernel to run at a VTL other than > + the normal VTL0, which currently is only VTL2. This option > + initializes the x86 platform for VTL2, and adds the ability to boot > + secondary CPUs directly into 64-bit context as required for VTLs other > + than 0. A kernel built with this option must run at VTL2, and will > + not run as a normal guest. > + > + If unsure, say N > + Is there a reason for putting this in arch/x86/Kconfig instead of in drivers/hv/Kconfig under the "Microsoft Hyper-V guest support" menu with the other Hyper-V settings? It seems like grouping this with the other Hyper-V settings would make it easier to find, unless there's some reason that doesn't work. Michael > config PARAVIRT > bool "Enable paravirtualization code" > depends on HAVE_STATIC_CALL > diff --git a/arch/x86/hyperv/Makefile b/arch/x86/hyperv/Makefile > index 5d2de10809ae..3a1548054b48 100644 > --- a/arch/x86/hyperv/Makefile > +++ b/arch/x86/hyperv/Makefile > @@ -1,6 +1,7 @@ > # SPDX-License-Identifier: GPL-2.0-only > obj-y := hv_init.o mmu.o nested.o irqdomain.o ivm.o > obj-$(CONFIG_X86_64) += hv_apic.o hv_proc.o > +obj-$(CONFIG_HYPERV_VTL_MODE) += hv_vtl.o > > ifdef CONFIG_X86_64 > obj-$(CONFIG_PARAVIRT_SPINLOCKS) += hv_spinlock.o > -- > 2.34.1
