179b05c1fSChristoph Hellwig# SPDX-License-Identifier: GPL-2.0 279b05c1fSChristoph Hellwig 3f163977dSChristoph Hellwigmenu "UML-specific options" 4f163977dSChristoph Hellwig 5f163977dSChristoph Hellwigconfig UML 6f163977dSChristoph Hellwig bool 7f163977dSChristoph Hellwig default y 8cb2c7d1aSMickaël Salaün select ARCH_HAS_CPU_FINALIZE_INIT 9*9349b5cdSThomas Gleixner select ARCH_HAS_FORTIFY_SOURCE 10ba38961aSKees Cook select ARCH_HAS_GCOV_PROFILE_ALL 112419ac32SVincent Whitchurch select ARCH_HAS_KCOV 12f163977dSChristoph Hellwig select ARCH_HAS_STRNCPY_FROM_USER 13e6226997SArnd Bergmann select ARCH_HAS_STRNLEN_USER 14e6226997SArnd Bergmann select ARCH_NO_PREEMPT 1587a4c375SChristoph Hellwig select HAVE_ARCH_AUDITSYSCALL 16f163977dSChristoph Hellwig select HAVE_ARCH_KASAN if X86_64 175b301409SPatricia Alfonso select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN 185b301409SPatricia Alfonso select HAVE_ARCH_SECCOMP_FILTER 19f163977dSChristoph Hellwig select HAVE_ASM_MODVERSIONS 202ff2b7ecSMasahiro Yamada select HAVE_UID16 21f163977dSChristoph Hellwig select HAVE_DEBUG_KMEMLEAK 22f163977dSChristoph Hellwig select HAVE_DEBUG_BUGVERBOSE 230d76433cSHernán Gonzalez select NO_DMA if !UML_DMA_EMULATION 2468f5d3f3SJohannes Berg select OF_EARLY_FLATTREE if OF 25b31297f0SVincent Whitchurch select GENERIC_IRQ_SHOW 26f163977dSChristoph Hellwig select GENERIC_CPU_DEVICES 27f163977dSChristoph Hellwig select HAVE_GCC_PLUGINS 28f163977dSChristoph Hellwig select ARCH_SUPPORTS_LTO_CLANG 2983e913f5SPeter Foley select ARCH_SUPPORTS_LTO_CLANG_THIN 3083e913f5SPeter Foley select TRACE_IRQFLAGS_SUPPORT 314aae683fSMasahiro Yamada select TTY # Needed for line.c 32f163977dSChristoph Hellwig select HAVE_ARCH_VMAP_STACK 33bc5c49d7SJohannes Berg select HAVE_RUST if X86_64 340438aadfSDavid Gow 35f163977dSChristoph Hellwigconfig MMU 36f163977dSChristoph Hellwig bool 37f163977dSChristoph Hellwig default y 38f163977dSChristoph Hellwig 39f163977dSChristoph Hellwigconfig UML_DMA_EMULATION 4068f5d3f3SJohannes Berg bool 4168f5d3f3SJohannes Berg 4268f5d3f3SJohannes Bergconfig NO_IOMEM 43f163977dSChristoph Hellwig bool "disable IOMEM" if EXPERT 440bbadafdSJohannes Berg depends on !INDIRECT_IOMEM 4568f5d3f3SJohannes Berg default y 460bbadafdSJohannes Berg 470bbadafdSJohannes Bergconfig UML_IOMEM_EMULATION 4868f5d3f3SJohannes Berg bool 4968f5d3f3SJohannes Berg select INDIRECT_IOMEM 5068f5d3f3SJohannes Berg select GENERIC_PCI_IOMAP 5168f5d3f3SJohannes Berg select GENERIC_IOMAP 5268f5d3f3SJohannes Berg select NO_GENERIC_PCI_IOPORT_MAP 5368f5d3f3SJohannes Berg 5468f5d3f3SJohannes Bergconfig NO_IOPORT_MAP 550bbadafdSJohannes Berg def_bool y 56f163977dSChristoph Hellwig 57f163977dSChristoph Hellwigconfig ISA 58f163977dSChristoph Hellwig bool 59f163977dSChristoph Hellwig 60f163977dSChristoph Hellwigconfig SBUS 61f163977dSChristoph Hellwig bool 62f163977dSChristoph Hellwig 63f163977dSChristoph Hellwigconfig LOCKDEP_SUPPORT 64f163977dSChristoph Hellwig bool 65f163977dSChristoph Hellwig default y 66f163977dSChristoph Hellwig 67f163977dSChristoph Hellwigconfig STACKTRACE_SUPPORT 68f163977dSChristoph Hellwig bool 69f163977dSChristoph Hellwig default y 70f163977dSChristoph Hellwig select STACKTRACE 71f163977dSChristoph Hellwig 72f163977dSChristoph Hellwigconfig GENERIC_CALIBRATE_DELAY 73f163977dSChristoph Hellwig bool 74f163977dSChristoph Hellwig default y 75f163977dSChristoph Hellwig 76f163977dSChristoph Hellwigconfig HZ 77f163977dSChristoph Hellwig int 78f163977dSChristoph Hellwig default 100 79f163977dSChristoph Hellwig 80f163977dSChristoph Hellwigconfig NR_CPUS 81f163977dSChristoph Hellwig int 82f163977dSChristoph Hellwig range 1 1 83f163977dSChristoph Hellwig default 1 84f163977dSChristoph Hellwig 85f163977dSChristoph Hellwigconfig ARCH_HAS_CACHE_LINE_SIZE 86d8fb32f4SAnton Ivanov def_bool y 87d8fb32f4SAnton Ivanov 88d8fb32f4SAnton Ivanovsource "arch/$(HEADER_ARCH)/um/Kconfig" 8979b05c1fSChristoph Hellwig 90f163977dSChristoph Hellwigconfig MAY_HAVE_RUNTIME_DEPS 91730586ffSIgnat Korchagin bool 9233631793SBrendan Higgins 9333631793SBrendan Higginsconfig STATIC_LINK 94f163977dSChristoph Hellwig bool "Force a static link" 95f163977dSChristoph Hellwig depends on CC_CAN_LINK_STATIC_NO_RUNTIME_DEPS || !MAY_HAVE_RUNTIME_DEPS 96730586ffSIgnat Korchagin help 97f163977dSChristoph Hellwig This option gives you the ability to force a static link of UML. 98f163977dSChristoph Hellwig Normally, UML is linked as a shared binary. This is inconvenient for 99f163977dSChristoph Hellwig use in a chroot jail. So, if you intend to run UML inside a chroot, 100f163977dSChristoph Hellwig you probably want to say Y here. 101f163977dSChristoph Hellwig Additionally, this option enables using higher memory spaces (up to 102f163977dSChristoph Hellwig 2.75G) for UML. 103f163977dSChristoph Hellwig 104f163977dSChristoph Hellwig NOTE: This option is incompatible with some networking features which 10533631793SBrendan Higgins depend on features that require being dynamically loaded (like NSS). 10633631793SBrendan Higgins 10733631793SBrendan Higginsconfig LD_SCRIPT_STATIC 108f163977dSChristoph Hellwig bool 109f163977dSChristoph Hellwig default y 110f163977dSChristoph Hellwig depends on STATIC_LINK 111f163977dSChristoph Hellwig 112f163977dSChristoph Hellwigconfig LD_SCRIPT_DYN 113f163977dSChristoph Hellwig bool 114f163977dSChristoph Hellwig default y 115f163977dSChristoph Hellwig depends on !LD_SCRIPT_STATIC 116f163977dSChristoph Hellwig 117f163977dSChristoph Hellwigconfig LD_SCRIPT_DYN_RPATH 118386093c6SJohannes Berg bool "set rpath in the binary" if EXPERT 119386093c6SJohannes Berg default y 120386093c6SJohannes Berg depends on LD_SCRIPT_DYN 121386093c6SJohannes Berg help 122386093c6SJohannes Berg Add /lib (and /lib64 for 64-bit) to the linux binary's rpath 123386093c6SJohannes Berg explicitly. 124386093c6SJohannes Berg 125386093c6SJohannes Berg You may need to turn this off if compiling for nix systems 126386093c6SJohannes Berg that have their libraries in random /nix directories and 127386093c6SJohannes Berg might otherwise unexpected use libraries from /lib or /lib64 128386093c6SJohannes Berg instead of the desired ones. 129386093c6SJohannes Berg 130386093c6SJohannes Bergconfig HOSTFS 131f163977dSChristoph Hellwig tristate "Host filesystem" 132f163977dSChristoph Hellwig help 133f163977dSChristoph Hellwig While the User-Mode Linux port uses its own root file system for 134f163977dSChristoph Hellwig booting and normal file access, this module lets the UML user 135f163977dSChristoph Hellwig access files stored on the host. It does not require any 136f163977dSChristoph Hellwig network connection between the Host and UML. An example use of 137f163977dSChristoph Hellwig this might be: 138f163977dSChristoph Hellwig 139f163977dSChristoph Hellwig mount none /tmp/fromhost -t hostfs -o /tmp/umlshare 140f163977dSChristoph Hellwig 141f163977dSChristoph Hellwig where /tmp/fromhost is an empty directory inside UML and 142f163977dSChristoph Hellwig /tmp/umlshare is a directory on the host with files the UML user 143f163977dSChristoph Hellwig wishes to access. 144f163977dSChristoph Hellwig 145f163977dSChristoph Hellwig For more information, see 146f163977dSChristoph Hellwig <http://user-mode-linux.sourceforge.net/hostfs.html>. 147f163977dSChristoph Hellwig 148f163977dSChristoph Hellwig If you'd like to be able to work with files stored on the host, 149f163977dSChristoph Hellwig say Y or M here; otherwise say N. 150f163977dSChristoph Hellwig 151f163977dSChristoph Hellwigconfig MCONSOLE 152f163977dSChristoph Hellwig bool "Management console" 153f163977dSChristoph Hellwig depends on PROC_FS 154f163977dSChristoph Hellwig default y 155f163977dSChristoph Hellwig help 156f163977dSChristoph Hellwig The user mode linux management console is a low-level interface to 157f163977dSChristoph Hellwig the kernel, somewhat like the i386 SysRq interface. Since there is 158f163977dSChristoph Hellwig a full-blown operating system running under every user mode linux 159f163977dSChristoph Hellwig instance, there is much greater flexibility possible than with the 160f163977dSChristoph Hellwig SysRq mechanism. 161f163977dSChristoph Hellwig 162f163977dSChristoph Hellwig If you answer 'Y' to this option, to use this feature, you need the 163f163977dSChristoph Hellwig mconsole client (called uml_mconsole) which is present in CVS in 164f163977dSChristoph Hellwig 2.4.5-9um and later (path /tools/mconsole), and is also in the 165f163977dSChristoph Hellwig distribution RPM package in 2.4.6 and later. 166f163977dSChristoph Hellwig 167f163977dSChristoph Hellwig It is safe to say 'Y' here. 168f163977dSChristoph Hellwig 169f163977dSChristoph Hellwigconfig MAGIC_SYSRQ 170f163977dSChristoph Hellwig bool "Magic SysRq key" 171f163977dSChristoph Hellwig depends on MCONSOLE 172f163977dSChristoph Hellwig help 173f163977dSChristoph Hellwig If you say Y here, you will have some control over the system even 174f163977dSChristoph Hellwig if the system crashes for example during kernel debugging (e.g., you 175f163977dSChristoph Hellwig will be able to flush the buffer cache to disk, reboot the system 176f163977dSChristoph Hellwig immediately or dump some status information). A key for each of the 177f163977dSChristoph Hellwig possible requests is provided. 178f163977dSChristoph Hellwig 179f163977dSChristoph Hellwig This is the feature normally accomplished by pressing a key 180f163977dSChristoph Hellwig while holding SysRq (Alt+PrintScreen). 181f163977dSChristoph Hellwig 182f163977dSChristoph Hellwig On UML, this is accomplished by sending a "sysrq" command with 183f163977dSChristoph Hellwig mconsole, followed by the letter for the requested command. 184f163977dSChristoph Hellwig 185f163977dSChristoph Hellwig The keys are documented in <file:Documentation/admin-guide/sysrq.rst>. Don't say Y 186f163977dSChristoph Hellwig unless you really know what this hack does. 187f163977dSChristoph Hellwig 188f163977dSChristoph Hellwigconfig KERNEL_STACK_ORDER 189f163977dSChristoph Hellwig int "Kernel stack size order" 190f163977dSChristoph Hellwig default 2 if 64BIT 1915c2ffce1SAnton Ivanov range 2 10 if 64BIT 1925c2ffce1SAnton Ivanov default 1 if !64BIT 1935c2ffce1SAnton Ivanov help 194f163977dSChristoph Hellwig This option determines the size of UML kernel stacks. They will 195f163977dSChristoph Hellwig be 1 << order pages. The default is OK unless you're running Valgrind 196f163977dSChristoph Hellwig on UML, in which case, set this to 3. 197f163977dSChristoph Hellwig It is possible to reduce the stack to 1 for 64BIT and 0 for 32BIT on 1985c2ffce1SAnton Ivanov older (pre-2017) CPUs. It is not recommended on newer CPUs due to the 1995c2ffce1SAnton Ivanov increase in the size of the state which needs to be saved when handling 2005c2ffce1SAnton Ivanov signals. 2015c2ffce1SAnton Ivanov 202f163977dSChristoph Hellwigconfig MMAPPER 203f163977dSChristoph Hellwig tristate "iomem emulation driver" 204f163977dSChristoph Hellwig help 205f163977dSChristoph Hellwig This driver allows a host file to be used as emulated IO memory inside 206f163977dSChristoph Hellwig UML. 207f163977dSChristoph Hellwig 208f163977dSChristoph Hellwigconfig PGTABLE_LEVELS 209f163977dSChristoph Hellwig int 210f163977dSChristoph Hellwig default 3 if 3_LEVEL_PGTABLES 211f163977dSChristoph Hellwig default 2 212f163977dSChristoph Hellwig 213f163977dSChristoph Hellwigconfig UML_TIME_TRAVEL_SUPPORT 21406503870SJohannes Berg bool 21506503870SJohannes Berg prompt "Support time-travel mode (e.g. for test execution)" 21606503870SJohannes Berg # inf-cpu mode is incompatible with the benchmarking 217d65197adSJohannes Berg depends on !RAID6_PQ_BENCHMARK 218d65197adSJohannes Berg depends on !SMP 2194b786e24SJohannes Berg help 22006503870SJohannes Berg Enable this option to support time travel inside the UML instance. 22106503870SJohannes Berg 22206503870SJohannes Berg After enabling this option, two modes are accessible at runtime 22306503870SJohannes Berg (selected by the kernel command line), see the kernel's command- 22406503870SJohannes Berg line help for more details. 22506503870SJohannes Berg 22606503870SJohannes Berg It is safe to say Y, but you probably don't need this. 22706503870SJohannes Berg 22806503870SJohannes Bergconfig KASAN_SHADOW_OFFSET 2295b301409SPatricia Alfonso hex 2305b301409SPatricia Alfonso depends on KASAN 2315b301409SPatricia Alfonso default 0x100000000000 2325b301409SPatricia Alfonso help 2335b301409SPatricia Alfonso This is the offset at which the ~16TB of shadow memory is 2345b301409SPatricia Alfonso mapped and used by KASAN for memory debugging. This can be any 2355b301409SPatricia Alfonso address that has at least KASAN_SHADOW_SIZE (total address space divided 2365b301409SPatricia Alfonso by 8) amount of space so that the KASAN shadow memory does not conflict 2375b301409SPatricia Alfonso with anything. The default is 0x100000000000, which works even if mem is 2385b301409SPatricia Alfonso set to a large value. On low-memory systems, try 0x7fff8000, as it fits 2395b301409SPatricia Alfonso into the immediate of most instructions, improving performance. 2405b301409SPatricia Alfonso 2415b301409SPatricia Alfonsoendmenu 242f163977dSChristoph Hellwig 243f163977dSChristoph Hellwigsource "arch/um/drivers/Kconfig" 2449bea1801SChristoph Hellwig 24592dcd3d3SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 24692dcd3d3SJohannes Berg def_bool y 24792dcd3d3SJohannes Berg 24892dcd3d3SJohannes Bergmenu "Power management options" 249f09c3fcfSPeter Foley 250f09c3fcfSPeter Foleysource "kernel/power/Kconfig" 25192dcd3d3SJohannes Berg 252f09c3fcfSPeter Foleyendmenu 253f09c3fcfSPeter Foley