1# SPDX-License-Identifier: GPL-2.0 2# 3# KVM configuration 4# 5 6source "virt/kvm/Kconfig" 7 8menuconfig VIRTUALIZATION 9 bool "Virtualization" 10 default y 11 help 12 Say Y here to get to see options for using your Linux host to run other 13 operating systems inside virtual machines (guests). 14 This option alone does not add any kernel code. 15 16 If you say N, all options in this submenu will be skipped and disabled. 17 18if VIRTUALIZATION 19 20config KVM 21 tristate "Kernel-based Virtual Machine (KVM) support" 22 depends on HIGH_RES_TIMERS 23 depends on X86_LOCAL_APIC 24 select KVM_COMMON 25 select KVM_GENERIC_MMU_NOTIFIER 26 select HAVE_KVM_IRQCHIP 27 select HAVE_KVM_PFNCACHE 28 select HAVE_KVM_DIRTY_RING_TSO 29 select HAVE_KVM_DIRTY_RING_ACQ_REL 30 select HAVE_KVM_IRQ_BYPASS 31 select HAVE_KVM_IRQ_ROUTING 32 select HAVE_KVM_READONLY_MEM 33 select KVM_ASYNC_PF 34 select USER_RETURN_NOTIFIER 35 select KVM_MMIO 36 select SCHED_INFO 37 select PERF_EVENTS 38 select GUEST_PERF_EVENTS 39 select HAVE_KVM_MSI 40 select HAVE_KVM_CPU_RELAX_INTERCEPT 41 select HAVE_KVM_NO_POLL 42 select KVM_XFER_TO_GUEST_WORK 43 select KVM_GENERIC_DIRTYLOG_READ_PROTECT 44 select KVM_VFIO 45 select HAVE_KVM_PM_NOTIFIER if PM 46 select KVM_GENERIC_HARDWARE_ENABLING 47 help 48 Support hosting fully virtualized guest machines using hardware 49 virtualization extensions. You will need a fairly recent 50 processor equipped with virtualization extensions. You will also 51 need to select one or more of the processor modules below. 52 53 This module provides access to the hardware capabilities through 54 a character device node named /dev/kvm. 55 56 To compile this as a module, choose M here: the module 57 will be called kvm. 58 59 If unsure, say N. 60 61config KVM_WERROR 62 bool "Compile KVM with -Werror" 63 # Disallow KVM's -Werror if KASAN is enabled, e.g. to guard against 64 # randomized configs from selecting KVM_WERROR=y, which doesn't play 65 # nice with KASAN. KASAN builds generates warnings for the default 66 # FRAME_WARN, i.e. KVM_WERROR=y with KASAN=y requires special tuning. 67 # Building KVM with -Werror and KASAN is still doable via enabling 68 # the kernel-wide WERROR=y. 69 depends on KVM && EXPERT && !KASAN 70 help 71 Add -Werror to the build flags for KVM. 72 73 If in doubt, say "N". 74 75config KVM_SW_PROTECTED_VM 76 bool "Enable support for KVM software-protected VMs" 77 depends on EXPERT 78 depends on KVM && X86_64 79 select KVM_GENERIC_PRIVATE_MEM 80 help 81 Enable support for KVM software-protected VMs. Currently, software- 82 protected VMs are purely a development and testing vehicle for 83 KVM_CREATE_GUEST_MEMFD. Attempting to run a "real" VM workload as a 84 software-protected VM will fail miserably. 85 86 If unsure, say "N". 87 88config KVM_INTEL 89 tristate "KVM for Intel (and compatible) processors support" 90 depends on KVM && IA32_FEAT_CTL 91 help 92 Provides support for KVM on processors equipped with Intel's VT 93 extensions, a.k.a. Virtual Machine Extensions (VMX). 94 95 To compile this as a module, choose M here: the module 96 will be called kvm-intel. 97 98config X86_SGX_KVM 99 bool "Software Guard eXtensions (SGX) Virtualization" 100 depends on X86_SGX && KVM_INTEL 101 help 102 103 Enables KVM guests to create SGX enclaves. 104 105 This includes support to expose "raw" unreclaimable enclave memory to 106 guests via a device node, e.g. /dev/sgx_vepc. 107 108 If unsure, say N. 109 110config KVM_AMD 111 tristate "KVM for AMD processors support" 112 depends on KVM && (CPU_SUP_AMD || CPU_SUP_HYGON) 113 help 114 Provides support for KVM on AMD processors equipped with the AMD-V 115 (SVM) extensions. 116 117 To compile this as a module, choose M here: the module 118 will be called kvm-amd. 119 120config KVM_AMD_SEV 121 bool "AMD Secure Encrypted Virtualization (SEV) support" 122 default y 123 depends on KVM_AMD && X86_64 124 depends on CRYPTO_DEV_SP_PSP && !(KVM_AMD=y && CRYPTO_DEV_CCP_DD=m) 125 select ARCH_HAS_CC_PLATFORM 126 help 127 Provides support for launching Encrypted VMs (SEV) and Encrypted VMs 128 with Encrypted State (SEV-ES) on AMD processors. 129 130config KVM_SMM 131 bool "System Management Mode emulation" 132 default y 133 depends on KVM 134 help 135 Provides support for KVM to emulate System Management Mode (SMM) 136 in virtual machines. This can be used by the virtual machine 137 firmware to implement UEFI secure boot. 138 139 If unsure, say Y. 140 141config KVM_HYPERV 142 bool "Support for Microsoft Hyper-V emulation" 143 depends on KVM 144 default y 145 help 146 Provides KVM support for emulating Microsoft Hyper-V. This allows KVM 147 to expose a subset of the paravirtualized interfaces defined in the 148 Hyper-V Hypervisor Top-Level Functional Specification (TLFS): 149 https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs 150 These interfaces are required for the correct and performant functioning 151 of Windows and Hyper-V guests on KVM. 152 153 If unsure, say "Y". 154 155config KVM_XEN 156 bool "Support for Xen hypercall interface" 157 depends on KVM 158 help 159 Provides KVM support for the hosting Xen HVM guests and 160 passing Xen hypercalls to userspace. 161 162 If in doubt, say "N". 163 164config KVM_PROVE_MMU 165 bool "Prove KVM MMU correctness" 166 depends on DEBUG_KERNEL 167 depends on KVM 168 depends on EXPERT 169 help 170 Enables runtime assertions in KVM's MMU that are too costly to enable 171 in anything remotely resembling a production environment, e.g. this 172 gates code that verifies a to-be-freed page table doesn't have any 173 present SPTEs. 174 175 If in doubt, say "N". 176 177config KVM_EXTERNAL_WRITE_TRACKING 178 bool 179 180config KVM_MAX_NR_VCPUS 181 int "Maximum number of vCPUs per KVM guest" 182 depends on KVM 183 range 1024 4096 184 default 4096 if MAXSMP 185 default 1024 186 help 187 Set the maximum number of vCPUs per KVM guest. Larger values will increase 188 the memory footprint of each KVM guest, regardless of how many vCPUs are 189 created for a given VM. 190 191endif # VIRTUALIZATION 192