# SPDX-License-Identifier: GPL-2.0 # # KVM configuration # source "virt/kvm/Kconfig" menuconfig VIRTUALIZATION bool "Virtualization" help Say Y here to get to see options for using your Linux host to run other operating systems inside virtual machines (guests). This option alone does not add any kernel code. If you say N, all options in this submenu will be skipped and disabled. if VIRTUALIZATION config KVM bool select PREEMPT_NOTIFIERS select HAVE_KVM_EVENTFD select HAVE_KVM_VCPU_ASYNC_IOCTL select SRCU select KVM_VFIO select IRQ_BYPASS_MANAGER select HAVE_KVM_IRQ_BYPASS select INTERVAL_TREE config KVM_BOOK3S_HANDLER bool config KVM_BOOK3S_32_HANDLER bool select KVM_BOOK3S_HANDLER select KVM_MMIO config KVM_BOOK3S_64_HANDLER bool select KVM_BOOK3S_HANDLER config KVM_BOOK3S_PR_POSSIBLE bool select KVM_MMIO select MMU_NOTIFIER config KVM_BOOK3S_HV_POSSIBLE bool config KVM_BOOK3S_32 tristate "KVM support for PowerPC book3s_32 processors" depends on PPC_BOOK3S_32 && !SMP && !PTE_64BIT select KVM select KVM_BOOK3S_32_HANDLER select KVM_BOOK3S_PR_POSSIBLE select PPC_FPU help Support running unmodified book3s_32 guest kernels in virtual machines on book3s_32 host processors. This module provides access to the hardware capabilities through a character device node named /dev/kvm. If unsure, say N. config KVM_BOOK3S_64 tristate "KVM support for PowerPC book3s_64 processors" depends on PPC_BOOK3S_64 select KVM_BOOK3S_64_HANDLER select KVM select KVM_BOOK3S_PR_POSSIBLE if !KVM_BOOK3S_HV_POSSIBLE select PPC_64S_HASH_MMU select SPAPR_TCE_IOMMU if IOMMU_SUPPORT && (PPC_PSERIES || PPC_POWERNV) help Support running unmodified book3s_64 and book3s_32 guest kernels in virtual machines on book3s_64 host processors. This module provides access to the hardware capabilities through a character device node named /dev/kvm. If unsure, say N. config KVM_BOOK3S_64_HV tristate "KVM for POWER7 and later using hypervisor mode in host" depends on KVM_BOOK3S_64 && PPC_POWERNV select KVM_BOOK3S_HV_POSSIBLE select MMU_NOTIFIER select CMA help Support running unmodified book3s_64 guest kernels in virtual machines on POWER7 and newer processors that have hypervisor mode available to the host. If you say Y here, KVM will use the hardware virtualization facilities of POWER7 (and later) processors, meaning that guest operating systems will run at full hardware speed using supervisor and user modes. However, this also means that KVM is not usable under PowerVM (pHyp), is only usable on POWER7 or later processors, and cannot emulate a different processor from the host processor. If unsure, say N. config KVM_BOOK3S_64_PR tristate "KVM support without using hypervisor mode in host" depends on KVM_BOOK3S_64 select KVM_BOOK3S_PR_POSSIBLE help Support running guest kernels in virtual machines on processors without using hypervisor mode in the host, by running the guest in user mode (problem state) and emulating all privileged instructions and registers. This is only available for hash MMU mode and only supports guests that use hash MMU mode. This is not as fast as using hypervisor mode, but works on machines where hypervisor mode is not available or not usable, and can emulate processors that are different from the host processor, including emulating 32-bit processors on a 64-bit host. Selecting this option will cause the SCV facility to be disabled when the kernel is booted on the pseries platform in hash MMU mode (regardless of PR VMs running). When any PR VMs are running, "AIL" mode is disabled which may slow interrupts and system calls on the host. config KVM_BOOK3S_HV_EXIT_TIMING bool config KVM_BOOK3S_HV_P9_TIMING bool "Detailed timing for the P9 entry point" select KVM_BOOK3S_HV_EXIT_TIMING depends on KVM_BOOK3S_HV_POSSIBLE && DEBUG_FS help Calculate time taken for each vcpu during vcpu entry and exit, time spent inside the guest and time spent handling hypercalls and page faults. The total, minimum and maximum times in nanoseconds together with the number of executions are reported in debugfs in kvm/vm#/vcpu#/timings. If unsure, say N. config KVM_BOOK3S_HV_P8_TIMING bool "Detailed timing for hypervisor real-mode code (for POWER8)" select KVM_BOOK3S_HV_EXIT_TIMING depends on KVM_BOOK3S_HV_POSSIBLE && DEBUG_FS && !KVM_BOOK3S_HV_P9_TIMING help Calculate time taken for each vcpu in the real-mode guest entry, exit, and interrupt handling code, plus time spent in the guest and in nap mode due to idle (cede) while other threads are still in the guest. The total, minimum and maximum times in nanoseconds together with the number of executions are reported in debugfs in kvm/vm#/vcpu#/timings. The overhead is of the order of 30 - 40 ns per exit on POWER8. If unsure, say N. config KVM_BOOK3S_HV_NESTED_PMU_WORKAROUND bool "Nested L0 host workaround for L1 KVM host PMU handling bug" if EXPERT depends on KVM_BOOK3S_HV_POSSIBLE default !EXPERT help Old nested HV capable Linux guests have a bug where they don't reflect the PMU in-use status of their L2 guest to the L0 host while the L2 PMU registers are live. This can result in loss of L2 PMU register state, causing perf to not work correctly in L2 guests. Selecting this option for the L0 host implements a workaround for those buggy L1s which saves the L2 state, at the cost of performance in all nested-capable guest entry/exit. config KVM_BOOKE_HV bool config KVM_EXIT_TIMING bool "Detailed exit timing" depends on KVM_E500V2 || KVM_E500MC help Calculate elapsed time for every exit/enter cycle. A per-vcpu report is available in debugfs kvm/vm#_vcpu#_timing. The overhead is relatively small, however it is not recommended for production environments. If unsure, say N. config KVM_E500V2 bool "KVM support for PowerPC E500v2 processors" depends on E500 && !PPC_E500MC select KVM select KVM_MMIO select MMU_NOTIFIER help Support running unmodified E500 guest kernels in virtual machines on E500v2 host processors. This module provides access to the hardware capabilities through a character device node named /dev/kvm. If unsure, say N. config KVM_E500MC bool "KVM support for PowerPC E500MC/E5500/E6500 processors" depends on PPC_E500MC select KVM select KVM_MMIO select KVM_BOOKE_HV select MMU_NOTIFIER help Support running unmodified E500MC/E5500/E6500 guest kernels in virtual machines on E500MC/E5500/E6500 host processors. This module provides access to the hardware capabilities through a character device node named /dev/kvm. If unsure, say N. config KVM_MPIC bool "KVM in-kernel MPIC emulation" depends on KVM && E500 select HAVE_KVM_IRQCHIP select HAVE_KVM_IRQFD select HAVE_KVM_IRQ_ROUTING select HAVE_KVM_MSI help Enable support for emulating MPIC devices inside the host kernel, rather than relying on userspace to emulate. Currently, support is limited to certain versions of Freescale's MPIC implementation. config KVM_XICS bool "KVM in-kernel XICS emulation" depends on KVM_BOOK3S_64 && !KVM_MPIC select HAVE_KVM_IRQCHIP select HAVE_KVM_IRQFD default y help Include support for the XICS (eXternal Interrupt Controller Specification) interrupt controller architecture used on IBM POWER (pSeries) servers. config KVM_XIVE bool default y depends on KVM_XICS && PPC_XIVE_NATIVE && KVM_BOOK3S_HV_POSSIBLE endif # VIRTUALIZATION