Kconfig (7038B)
1# SPDX-License-Identifier: GPL-2.0 2# 3# KVM configuration 4# 5 6source "virt/kvm/Kconfig" 7 8menuconfig VIRTUALIZATION 9 bool "Virtualization" 10 help 11 Say Y here to get to see options for using your Linux host to run 12 other operating systems inside virtual machines (guests). 13 This option alone does not add any kernel code. 14 15 If you say N, all options in this submenu will be skipped and 16 disabled. 17 18if VIRTUALIZATION 19 20config KVM 21 bool 22 select PREEMPT_NOTIFIERS 23 select HAVE_KVM_EVENTFD 24 select HAVE_KVM_VCPU_ASYNC_IOCTL 25 select SRCU 26 select KVM_VFIO 27 select IRQ_BYPASS_MANAGER 28 select HAVE_KVM_IRQ_BYPASS 29 select INTERVAL_TREE 30 31config KVM_BOOK3S_HANDLER 32 bool 33 34config KVM_BOOK3S_32_HANDLER 35 bool 36 select KVM_BOOK3S_HANDLER 37 select KVM_MMIO 38 39config KVM_BOOK3S_64_HANDLER 40 bool 41 select KVM_BOOK3S_HANDLER 42 43config KVM_BOOK3S_PR_POSSIBLE 44 bool 45 select KVM_MMIO 46 select MMU_NOTIFIER 47 48config KVM_BOOK3S_HV_POSSIBLE 49 bool 50 51config KVM_BOOK3S_32 52 tristate "KVM support for PowerPC book3s_32 processors" 53 depends on PPC_BOOK3S_32 && !SMP && !PTE_64BIT 54 select KVM 55 select KVM_BOOK3S_32_HANDLER 56 select KVM_BOOK3S_PR_POSSIBLE 57 select PPC_FPU 58 help 59 Support running unmodified book3s_32 guest kernels 60 in virtual machines on book3s_32 host processors. 61 62 This module provides access to the hardware capabilities through 63 a character device node named /dev/kvm. 64 65 If unsure, say N. 66 67config KVM_BOOK3S_64 68 tristate "KVM support for PowerPC book3s_64 processors" 69 depends on PPC_BOOK3S_64 70 select KVM_BOOK3S_64_HANDLER 71 select KVM 72 select KVM_BOOK3S_PR_POSSIBLE if !KVM_BOOK3S_HV_POSSIBLE 73 select PPC_64S_HASH_MMU 74 select SPAPR_TCE_IOMMU if IOMMU_SUPPORT && (PPC_PSERIES || PPC_POWERNV) 75 help 76 Support running unmodified book3s_64 and book3s_32 guest kernels 77 in virtual machines on book3s_64 host processors. 78 79 This module provides access to the hardware capabilities through 80 a character device node named /dev/kvm. 81 82 If unsure, say N. 83 84config KVM_BOOK3S_64_HV 85 tristate "KVM for POWER7 and later using hypervisor mode in host" 86 depends on KVM_BOOK3S_64 && PPC_POWERNV 87 select KVM_BOOK3S_HV_POSSIBLE 88 select MMU_NOTIFIER 89 select CMA 90 help 91 Support running unmodified book3s_64 guest kernels in 92 virtual machines on POWER7 and newer processors that have 93 hypervisor mode available to the host. 94 95 If you say Y here, KVM will use the hardware virtualization 96 facilities of POWER7 (and later) processors, meaning that 97 guest operating systems will run at full hardware speed 98 using supervisor and user modes. However, this also means 99 that KVM is not usable under PowerVM (pHyp), is only usable 100 on POWER7 or later processors, and cannot emulate a 101 different processor from the host processor. 102 103 If unsure, say N. 104 105config KVM_BOOK3S_64_PR 106 tristate "KVM support without using hypervisor mode in host" 107 depends on KVM_BOOK3S_64 108 select KVM_BOOK3S_PR_POSSIBLE 109 help 110 Support running guest kernels in virtual machines on processors 111 without using hypervisor mode in the host, by running the 112 guest in user mode (problem state) and emulating all 113 privileged instructions and registers. 114 115 This is only available for hash MMU mode and only supports 116 guests that use hash MMU mode. 117 118 This is not as fast as using hypervisor mode, but works on 119 machines where hypervisor mode is not available or not usable, 120 and can emulate processors that are different from the host 121 processor, including emulating 32-bit processors on a 64-bit 122 host. 123 124 Selecting this option will cause the SCV facility to be 125 disabled when the kernel is booted on the pseries platform in 126 hash MMU mode (regardless of PR VMs running). When any PR VMs 127 are running, "AIL" mode is disabled which may slow interrupts 128 and system calls on the host. 129 130config KVM_BOOK3S_HV_EXIT_TIMING 131 bool "Detailed timing for hypervisor real-mode code" 132 depends on KVM_BOOK3S_HV_POSSIBLE && DEBUG_FS 133 help 134 Calculate time taken for each vcpu in the real-mode guest entry, 135 exit, and interrupt handling code, plus time spent in the guest 136 and in nap mode due to idle (cede) while other threads are still 137 in the guest. The total, minimum and maximum times in nanoseconds 138 together with the number of executions are reported in debugfs in 139 kvm/vm#/vcpu#/timings. The overhead is of the order of 30 - 40 140 ns per exit on POWER8. 141 142 If unsure, say N. 143 144config KVM_BOOK3S_HV_NESTED_PMU_WORKAROUND 145 bool "Nested L0 host workaround for L1 KVM host PMU handling bug" if EXPERT 146 depends on KVM_BOOK3S_HV_POSSIBLE 147 default !EXPERT 148 help 149 Old nested HV capable Linux guests have a bug where they don't 150 reflect the PMU in-use status of their L2 guest to the L0 host 151 while the L2 PMU registers are live. This can result in loss 152 of L2 PMU register state, causing perf to not work correctly in 153 L2 guests. 154 155 Selecting this option for the L0 host implements a workaround for 156 those buggy L1s which saves the L2 state, at the cost of performance 157 in all nested-capable guest entry/exit. 158 159config KVM_BOOKE_HV 160 bool 161 162config KVM_EXIT_TIMING 163 bool "Detailed exit timing" 164 depends on KVM_E500V2 || KVM_E500MC 165 help 166 Calculate elapsed time for every exit/enter cycle. A per-vcpu 167 report is available in debugfs kvm/vm#_vcpu#_timing. 168 The overhead is relatively small, however it is not recommended for 169 production environments. 170 171 If unsure, say N. 172 173config KVM_E500V2 174 bool "KVM support for PowerPC E500v2 processors" 175 depends on E500 && !PPC_E500MC 176 select KVM 177 select KVM_MMIO 178 select MMU_NOTIFIER 179 help 180 Support running unmodified E500 guest kernels in virtual machines on 181 E500v2 host processors. 182 183 This module provides access to the hardware capabilities through 184 a character device node named /dev/kvm. 185 186 If unsure, say N. 187 188config KVM_E500MC 189 bool "KVM support for PowerPC E500MC/E5500/E6500 processors" 190 depends on PPC_E500MC 191 select KVM 192 select KVM_MMIO 193 select KVM_BOOKE_HV 194 select MMU_NOTIFIER 195 help 196 Support running unmodified E500MC/E5500/E6500 guest kernels in 197 virtual machines on E500MC/E5500/E6500 host processors. 198 199 This module provides access to the hardware capabilities through 200 a character device node named /dev/kvm. 201 202 If unsure, say N. 203 204config KVM_MPIC 205 bool "KVM in-kernel MPIC emulation" 206 depends on KVM && E500 207 select HAVE_KVM_IRQCHIP 208 select HAVE_KVM_IRQFD 209 select HAVE_KVM_IRQ_ROUTING 210 select HAVE_KVM_MSI 211 help 212 Enable support for emulating MPIC devices inside the 213 host kernel, rather than relying on userspace to emulate. 214 Currently, support is limited to certain versions of 215 Freescale's MPIC implementation. 216 217config KVM_XICS 218 bool "KVM in-kernel XICS emulation" 219 depends on KVM_BOOK3S_64 && !KVM_MPIC 220 select HAVE_KVM_IRQCHIP 221 select HAVE_KVM_IRQFD 222 default y 223 help 224 Include support for the XICS (eXternal Interrupt Controller 225 Specification) interrupt controller architecture used on 226 IBM POWER (pSeries) servers. 227 228config KVM_XIVE 229 bool 230 default y 231 depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE 232 233endif # VIRTUALIZATION