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 KVM_INTEL_PROVE_VE 99 bool "Check that guests do not receive #VE exceptions" 100 default KVM_PROVE_MMU || DEBUG_KERNEL 101 depends on KVM_INTEL 102 help 103 104 Checks that KVM's page table management code will not incorrectly 105 let guests receive a virtualization exception. Virtualization 106 exceptions will be trapped by the hypervisor rather than injected 107 in the guest. 108 109 If unsure, say N. 110 111config X86_SGX_KVM 112 bool "Software Guard eXtensions (SGX) Virtualization" 113 depends on X86_SGX && KVM_INTEL 114 help 115 116 Enables KVM guests to create SGX enclaves. 117 118 This includes support to expose "raw" unreclaimable enclave memory to 119 guests via a device node, e.g. /dev/sgx_vepc. 120 121 If unsure, say N. 122 123config KVM_AMD 124 tristate "KVM for AMD processors support" 125 depends on KVM && (CPU_SUP_AMD || CPU_SUP_HYGON) 126 help 127 Provides support for KVM on AMD processors equipped with the AMD-V 128 (SVM) extensions. 129 130 To compile this as a module, choose M here: the module 131 will be called kvm-amd. 132 133config KVM_AMD_SEV 134 bool "AMD Secure Encrypted Virtualization (SEV) support" 135 default y 136 depends on KVM_AMD && X86_64 137 depends on CRYPTO_DEV_SP_PSP && !(KVM_AMD=y && CRYPTO_DEV_CCP_DD=m) 138 select ARCH_HAS_CC_PLATFORM 139 help 140 Provides support for launching Encrypted VMs (SEV) and Encrypted VMs 141 with Encrypted State (SEV-ES) on AMD processors. 142 143config KVM_SMM 144 bool "System Management Mode emulation" 145 default y 146 depends on KVM 147 help 148 Provides support for KVM to emulate System Management Mode (SMM) 149 in virtual machines. This can be used by the virtual machine 150 firmware to implement UEFI secure boot. 151 152 If unsure, say Y. 153 154config KVM_HYPERV 155 bool "Support for Microsoft Hyper-V emulation" 156 depends on KVM 157 default y 158 help 159 Provides KVM support for emulating Microsoft Hyper-V. This allows KVM 160 to expose a subset of the paravirtualized interfaces defined in the 161 Hyper-V Hypervisor Top-Level Functional Specification (TLFS): 162 https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs 163 These interfaces are required for the correct and performant functioning 164 of Windows and Hyper-V guests on KVM. 165 166 If unsure, say "Y". 167 168config KVM_XEN 169 bool "Support for Xen hypercall interface" 170 depends on KVM 171 help 172 Provides KVM support for the hosting Xen HVM guests and 173 passing Xen hypercalls to userspace. 174 175 If in doubt, say "N". 176 177config KVM_PROVE_MMU 178 bool "Prove KVM MMU correctness" 179 depends on DEBUG_KERNEL 180 depends on KVM 181 depends on EXPERT 182 help 183 Enables runtime assertions in KVM's MMU that are too costly to enable 184 in anything remotely resembling a production environment, e.g. this 185 gates code that verifies a to-be-freed page table doesn't have any 186 present SPTEs. 187 188 If in doubt, say "N". 189 190config KVM_EXTERNAL_WRITE_TRACKING 191 bool 192 193config KVM_MAX_NR_VCPUS 194 int "Maximum number of vCPUs per KVM guest" 195 depends on KVM 196 range 1024 4096 197 default 4096 if MAXSMP 198 default 1024 199 help 200 Set the maximum number of vCPUs per KVM guest. Larger values will increase 201 the memory footprint of each KVM guest, regardless of how many vCPUs are 202 created for a given VM. 203 204endif # VIRTUALIZATION 205