arch/x86/kvm/Kconfig

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # KVM configuration
   4 #
   5
   6 source "virt/kvm/Kconfig"
   7
   8 menuconfig VIRTUALIZATION
   9         bool "Virtualization"
  10         depends on HAVE_KVM || X86
  11         default y
  12         help
  13           Say Y here to get to see options for using your Linux host to run other
  14           operating systems inside virtual machines (guests).
  15           This option alone does not add any kernel code.
  16
  17           If you say N, all options in this submenu will be skipped and disabled.
  18
  19 if VIRTUALIZATION
  20
  21 config KVM
  22         tristate "Kernel-based Virtual Machine (KVM) support"
  23         depends on HAVE_KVM
  24         depends on HIGH_RES_TIMERS
  25         depends on X86_LOCAL_APIC
  26         select PREEMPT_NOTIFIERS
  27         select KVM_GENERIC_MMU_NOTIFIER
  28         select HAVE_KVM_IRQCHIP
  29         select HAVE_KVM_PFNCACHE
  30         select HAVE_KVM_DIRTY_RING_TSO
  31         select HAVE_KVM_DIRTY_RING_ACQ_REL
  32         select IRQ_BYPASS_MANAGER
  33         select HAVE_KVM_IRQ_BYPASS
  34         select HAVE_KVM_IRQ_ROUTING
  35         select KVM_ASYNC_PF
  36         select USER_RETURN_NOTIFIER
  37         select KVM_MMIO
  38         select SCHED_INFO
  39         select PERF_EVENTS
  40         select GUEST_PERF_EVENTS
  41         select HAVE_KVM_MSI
  42         select HAVE_KVM_CPU_RELAX_INTERCEPT
  43         select HAVE_KVM_NO_POLL
  44         select KVM_XFER_TO_GUEST_WORK
  45         select KVM_GENERIC_DIRTYLOG_READ_PROTECT
  46         select KVM_VFIO
  47         select INTERVAL_TREE
  48         select HAVE_KVM_PM_NOTIFIER if PM
  49         select KVM_GENERIC_HARDWARE_ENABLING
  50         help
  51           Support hosting fully virtualized guest machines using hardware
  52           virtualization extensions.  You will need a fairly recent
  53           processor equipped with virtualization extensions. You will also
  54           need to select one or more of the processor modules below.
  55
  56           This module provides access to the hardware capabilities through
  57           a character device node named /dev/kvm.
  58
  59           To compile this as a module, choose M here: the module
  60           will be called kvm.
  61
  62           If unsure, say N.
  63
  64 config KVM_WERROR
  65         bool "Compile KVM with -Werror"
  66         # KASAN may cause the build to fail due to larger frames
  67         default y if X86_64 && !KASAN
  68         # We use the dependency on !COMPILE_TEST to not be enabled
  69         # blindly in allmodconfig or allyesconfig configurations
  70         depends on KVM
  71         depends on (X86_64 && !KASAN) || !COMPILE_TEST
  72         depends on EXPERT
  73         help
  74           Add -Werror to the build flags for KVM.
  75
  76           If in doubt, say "N".
  77
  78 config KVM_SW_PROTECTED_VM
  79         bool "Enable support for KVM software-protected VMs"
  80         depends on EXPERT
  81         depends on X86_64
  82         select KVM_GENERIC_PRIVATE_MEM
  83         help
  84           Enable support for KVM software-protected VMs.  Currently "protected"
  85           means the VM can be backed with memory provided by
  86           KVM_CREATE_GUEST_MEMFD.
  87
  88           If unsure, say "N".
  89
  90 config KVM_INTEL
  91         tristate "KVM for Intel (and compatible) processors support"
  92         depends on KVM && IA32_FEAT_CTL
  93         help
  94           Provides support for KVM on processors equipped with Intel's VT
  95           extensions, a.k.a. Virtual Machine Extensions (VMX).
  96
  97           To compile this as a module, choose M here: the module
  98           will be called kvm-intel.
  99
 100 config X86_SGX_KVM
 101         bool "Software Guard eXtensions (SGX) Virtualization"
 102         depends on X86_SGX && KVM_INTEL
 103         help
 104
 105           Enables KVM guests to create SGX enclaves.
 106
 107           This includes support to expose "raw" unreclaimable enclave memory to
 108           guests via a device node, e.g. /dev/sgx_vepc.
 109
 110           If unsure, say N.
 111
 112 config KVM_AMD
 113         tristate "KVM for AMD processors support"
 114         depends on KVM && (CPU_SUP_AMD || CPU_SUP_HYGON)
 115         help
 116           Provides support for KVM on AMD processors equipped with the AMD-V
 117           (SVM) extensions.
 118
 119           To compile this as a module, choose M here: the module
 120           will be called kvm-amd.
 121
 122 config KVM_AMD_SEV
 123         def_bool y
 124         bool "AMD Secure Encrypted Virtualization (SEV) support"
 125         depends on KVM_AMD && X86_64
 126         depends on CRYPTO_DEV_SP_PSP && !(KVM_AMD=y && CRYPTO_DEV_CCP_DD=m)
 127         help
 128           Provides support for launching Encrypted VMs (SEV) and Encrypted VMs
 129           with Encrypted State (SEV-ES) on AMD processors.
 130
 131 config KVM_SMM
 132         bool "System Management Mode emulation"
 133         default y
 134         depends on KVM
 135         help
 136           Provides support for KVM to emulate System Management Mode (SMM)
 137           in virtual machines.  This can be used by the virtual machine
 138           firmware to implement UEFI secure boot.
 139
 140           If unsure, say Y.
 141
 142 config KVM_XEN
 143         bool "Support for Xen hypercall interface"
 144         depends on KVM
 145         help
 146           Provides KVM support for the hosting Xen HVM guests and
 147           passing Xen hypercalls to userspace.
 148
 149           If in doubt, say "N".
 150
 151 config KVM_PROVE_MMU
 152         bool "Prove KVM MMU correctness"
 153         depends on DEBUG_KERNEL
 154         depends on KVM
 155         depends on EXPERT
 156         help
 157           Enables runtime assertions in KVM's MMU that are too costly to enable
 158           in anything remotely resembling a production environment, e.g. this
 159           gates code that verifies a to-be-freed page table doesn't have any
 160           present SPTEs.
 161
 162           If in doubt, say "N".
 163
 164 config KVM_EXTERNAL_WRITE_TRACKING
 165         bool
 166
 167 config KVM_MAX_NR_VCPUS
 168         int "Maximum number of vCPUs per KVM guest"
 169         depends on KVM
 170         range 1024 4096
 171         default 4096 if MAXSMP
 172         default 1024
 173         help
 174           Set the maximum number of vCPUs per KVM guest. Larger values will increase
 175           the memory footprint of each KVM guest, regardless of how many vCPUs are
 176           created for a given VM.
 177
 178 endif # VIRTUALIZATION