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_EPHEMERAL_INODES 9*ba38961aSKees Cook select ARCH_HAS_FORTIFY_SOURCE 102419ac32SVincent Whitchurch select ARCH_HAS_GCOV_PROFILE_ALL 11f163977dSChristoph Hellwig select ARCH_HAS_KCOV 12e6226997SArnd Bergmann select ARCH_HAS_STRNCPY_FROM_USER 13e6226997SArnd Bergmann select ARCH_HAS_STRNLEN_USER 1487a4c375SChristoph Hellwig select ARCH_NO_PREEMPT 15f163977dSChristoph Hellwig select HAVE_ARCH_AUDITSYSCALL 165b301409SPatricia Alfonso select HAVE_ARCH_KASAN if X86_64 175b301409SPatricia Alfonso select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN 18f163977dSChristoph Hellwig select HAVE_ARCH_SECCOMP_FILTER 192ff2b7ecSMasahiro Yamada select HAVE_ASM_MODVERSIONS 20f163977dSChristoph Hellwig select HAVE_UID16 21f163977dSChristoph Hellwig select HAVE_DEBUG_KMEMLEAK 220d76433cSHernán Gonzalez select HAVE_DEBUG_BUGVERBOSE 2368f5d3f3SJohannes Berg select NO_DMA if !UML_DMA_EMULATION 24b31297f0SVincent Whitchurch select OF_EARLY_FLATTREE if OF 25f163977dSChristoph Hellwig select GENERIC_IRQ_SHOW 26f163977dSChristoph Hellwig select GENERIC_CPU_DEVICES 27f163977dSChristoph Hellwig select HAVE_GCC_PLUGINS 284aae683fSMasahiro Yamada select TRACE_IRQFLAGS_SUPPORT 29f163977dSChristoph Hellwig select TTY # Needed for line.c 30bc5c49d7SJohannes Berg select HAVE_ARCH_VMAP_STACK 31f163977dSChristoph Hellwig 32f163977dSChristoph Hellwigconfig MMU 33f163977dSChristoph Hellwig bool 34f163977dSChristoph Hellwig default y 35f163977dSChristoph Hellwig 3668f5d3f3SJohannes Bergconfig UML_DMA_EMULATION 3768f5d3f3SJohannes Berg bool 3868f5d3f3SJohannes Berg 39f163977dSChristoph Hellwigconfig NO_IOMEM 400bbadafdSJohannes Berg bool "disable IOMEM" if EXPERT 4168f5d3f3SJohannes Berg depends on !INDIRECT_IOMEM 420bbadafdSJohannes Berg default y 430bbadafdSJohannes Berg 4468f5d3f3SJohannes Bergconfig UML_IOMEM_EMULATION 4568f5d3f3SJohannes Berg bool 4668f5d3f3SJohannes Berg select INDIRECT_IOMEM 4768f5d3f3SJohannes Berg select GENERIC_PCI_IOMAP 4868f5d3f3SJohannes Berg select GENERIC_IOMAP 4968f5d3f3SJohannes Berg select NO_GENERIC_PCI_IOPORT_MAP 5068f5d3f3SJohannes Berg 510bbadafdSJohannes Bergconfig NO_IOPORT_MAP 52f163977dSChristoph Hellwig def_bool y 53f163977dSChristoph Hellwig 54f163977dSChristoph Hellwigconfig ISA 55f163977dSChristoph Hellwig bool 56f163977dSChristoph Hellwig 57f163977dSChristoph Hellwigconfig SBUS 58f163977dSChristoph Hellwig bool 59f163977dSChristoph Hellwig 60f163977dSChristoph Hellwigconfig LOCKDEP_SUPPORT 61f163977dSChristoph Hellwig bool 62f163977dSChristoph Hellwig default y 63f163977dSChristoph Hellwig 64f163977dSChristoph Hellwigconfig STACKTRACE_SUPPORT 65f163977dSChristoph Hellwig bool 66f163977dSChristoph Hellwig default y 67f163977dSChristoph Hellwig select STACKTRACE 68f163977dSChristoph Hellwig 69f163977dSChristoph Hellwigconfig GENERIC_CALIBRATE_DELAY 70f163977dSChristoph Hellwig bool 71f163977dSChristoph Hellwig default y 72f163977dSChristoph Hellwig 73f163977dSChristoph Hellwigconfig HZ 74f163977dSChristoph Hellwig int 75f163977dSChristoph Hellwig default 100 76f163977dSChristoph Hellwig 77f163977dSChristoph Hellwigconfig NR_CPUS 78f163977dSChristoph Hellwig int 79f163977dSChristoph Hellwig range 1 1 80f163977dSChristoph Hellwig default 1 81f163977dSChristoph Hellwig 82d8fb32f4SAnton Ivanovconfig ARCH_HAS_CACHE_LINE_SIZE 83d8fb32f4SAnton Ivanov def_bool y 84d8fb32f4SAnton Ivanov 8579b05c1fSChristoph Hellwigsource "arch/$(HEADER_ARCH)/um/Kconfig" 86f163977dSChristoph Hellwig 87730586ffSIgnat Korchaginconfig MAY_HAVE_RUNTIME_DEPS 8833631793SBrendan Higgins bool 8933631793SBrendan Higgins 90f163977dSChristoph Hellwigconfig STATIC_LINK 91f163977dSChristoph Hellwig bool "Force a static link" 92730586ffSIgnat Korchagin depends on CC_CAN_LINK_STATIC_NO_RUNTIME_DEPS || !MAY_HAVE_RUNTIME_DEPS 93f163977dSChristoph Hellwig help 94f163977dSChristoph Hellwig This option gives you the ability to force a static link of UML. 95f163977dSChristoph Hellwig Normally, UML is linked as a shared binary. This is inconvenient for 96f163977dSChristoph Hellwig use in a chroot jail. So, if you intend to run UML inside a chroot, 97f163977dSChristoph Hellwig you probably want to say Y here. 98f163977dSChristoph Hellwig Additionally, this option enables using higher memory spaces (up to 99f163977dSChristoph Hellwig 2.75G) for UML. 100f163977dSChristoph Hellwig 10133631793SBrendan Higgins NOTE: This option is incompatible with some networking features which 10233631793SBrendan Higgins depend on features that require being dynamically loaded (like NSS). 10333631793SBrendan Higgins 104f163977dSChristoph Hellwigconfig LD_SCRIPT_STATIC 105f163977dSChristoph Hellwig bool 106f163977dSChristoph Hellwig default y 107f163977dSChristoph Hellwig depends on STATIC_LINK 108f163977dSChristoph Hellwig 109f163977dSChristoph Hellwigconfig LD_SCRIPT_DYN 110f163977dSChristoph Hellwig bool 111f163977dSChristoph Hellwig default y 112f163977dSChristoph Hellwig depends on !LD_SCRIPT_STATIC 113f163977dSChristoph Hellwig 114386093c6SJohannes Bergconfig LD_SCRIPT_DYN_RPATH 115386093c6SJohannes Berg bool "set rpath in the binary" if EXPERT 116386093c6SJohannes Berg default y 117386093c6SJohannes Berg depends on LD_SCRIPT_DYN 118386093c6SJohannes Berg help 119386093c6SJohannes Berg Add /lib (and /lib64 for 64-bit) to the linux binary's rpath 120386093c6SJohannes Berg explicitly. 121386093c6SJohannes Berg 122386093c6SJohannes Berg You may need to turn this off if compiling for nix systems 123386093c6SJohannes Berg that have their libraries in random /nix directories and 124386093c6SJohannes Berg might otherwise unexpected use libraries from /lib or /lib64 125386093c6SJohannes Berg instead of the desired ones. 126386093c6SJohannes Berg 127f163977dSChristoph Hellwigconfig HOSTFS 128f163977dSChristoph Hellwig tristate "Host filesystem" 129f163977dSChristoph Hellwig help 130f163977dSChristoph Hellwig While the User-Mode Linux port uses its own root file system for 131f163977dSChristoph Hellwig booting and normal file access, this module lets the UML user 132f163977dSChristoph Hellwig access files stored on the host. It does not require any 133f163977dSChristoph Hellwig network connection between the Host and UML. An example use of 134f163977dSChristoph Hellwig this might be: 135f163977dSChristoph Hellwig 136f163977dSChristoph Hellwig mount none /tmp/fromhost -t hostfs -o /tmp/umlshare 137f163977dSChristoph Hellwig 138f163977dSChristoph Hellwig where /tmp/fromhost is an empty directory inside UML and 139f163977dSChristoph Hellwig /tmp/umlshare is a directory on the host with files the UML user 140f163977dSChristoph Hellwig wishes to access. 141f163977dSChristoph Hellwig 142f163977dSChristoph Hellwig For more information, see 143f163977dSChristoph Hellwig <http://user-mode-linux.sourceforge.net/hostfs.html>. 144f163977dSChristoph Hellwig 145f163977dSChristoph Hellwig If you'd like to be able to work with files stored on the host, 146f163977dSChristoph Hellwig say Y or M here; otherwise say N. 147f163977dSChristoph Hellwig 148f163977dSChristoph Hellwigconfig MCONSOLE 149f163977dSChristoph Hellwig bool "Management console" 150f163977dSChristoph Hellwig depends on PROC_FS 151f163977dSChristoph Hellwig default y 152f163977dSChristoph Hellwig help 153f163977dSChristoph Hellwig The user mode linux management console is a low-level interface to 154f163977dSChristoph Hellwig the kernel, somewhat like the i386 SysRq interface. Since there is 155f163977dSChristoph Hellwig a full-blown operating system running under every user mode linux 156f163977dSChristoph Hellwig instance, there is much greater flexibility possible than with the 157f163977dSChristoph Hellwig SysRq mechanism. 158f163977dSChristoph Hellwig 159f163977dSChristoph Hellwig If you answer 'Y' to this option, to use this feature, you need the 160f163977dSChristoph Hellwig mconsole client (called uml_mconsole) which is present in CVS in 161f163977dSChristoph Hellwig 2.4.5-9um and later (path /tools/mconsole), and is also in the 162f163977dSChristoph Hellwig distribution RPM package in 2.4.6 and later. 163f163977dSChristoph Hellwig 164f163977dSChristoph Hellwig It is safe to say 'Y' here. 165f163977dSChristoph Hellwig 166f163977dSChristoph Hellwigconfig MAGIC_SYSRQ 167f163977dSChristoph Hellwig bool "Magic SysRq key" 168f163977dSChristoph Hellwig depends on MCONSOLE 169f163977dSChristoph Hellwig help 170f163977dSChristoph Hellwig If you say Y here, you will have some control over the system even 171f163977dSChristoph Hellwig if the system crashes for example during kernel debugging (e.g., you 172f163977dSChristoph Hellwig will be able to flush the buffer cache to disk, reboot the system 173f163977dSChristoph Hellwig immediately or dump some status information). A key for each of the 174f163977dSChristoph Hellwig possible requests is provided. 175f163977dSChristoph Hellwig 176f163977dSChristoph Hellwig This is the feature normally accomplished by pressing a key 177f163977dSChristoph Hellwig while holding SysRq (Alt+PrintScreen). 178f163977dSChristoph Hellwig 179f163977dSChristoph Hellwig On UML, this is accomplished by sending a "sysrq" command with 180f163977dSChristoph Hellwig mconsole, followed by the letter for the requested command. 181f163977dSChristoph Hellwig 182f163977dSChristoph Hellwig The keys are documented in <file:Documentation/admin-guide/sysrq.rst>. Don't say Y 183f163977dSChristoph Hellwig unless you really know what this hack does. 184f163977dSChristoph Hellwig 185f163977dSChristoph Hellwigconfig KERNEL_STACK_ORDER 186f163977dSChristoph Hellwig int "Kernel stack size order" 1875c2ffce1SAnton Ivanov default 2 if 64BIT 1885c2ffce1SAnton Ivanov range 2 10 if 64BIT 1895c2ffce1SAnton Ivanov default 1 if !64BIT 190f163977dSChristoph Hellwig help 191f163977dSChristoph Hellwig This option determines the size of UML kernel stacks. They will 192f163977dSChristoph Hellwig be 1 << order pages. The default is OK unless you're running Valgrind 193f163977dSChristoph Hellwig on UML, in which case, set this to 3. 1945c2ffce1SAnton Ivanov It is possible to reduce the stack to 1 for 64BIT and 0 for 32BIT on 1955c2ffce1SAnton Ivanov older (pre-2017) CPUs. It is not recommended on newer CPUs due to the 1965c2ffce1SAnton Ivanov increase in the size of the state which needs to be saved when handling 1975c2ffce1SAnton Ivanov signals. 198f163977dSChristoph Hellwig 199f163977dSChristoph Hellwigconfig MMAPPER 200f163977dSChristoph Hellwig tristate "iomem emulation driver" 201f163977dSChristoph Hellwig help 202f163977dSChristoph Hellwig This driver allows a host file to be used as emulated IO memory inside 203f163977dSChristoph Hellwig UML. 204f163977dSChristoph Hellwig 205f163977dSChristoph Hellwigconfig PGTABLE_LEVELS 206f163977dSChristoph Hellwig int 207f163977dSChristoph Hellwig default 3 if 3_LEVEL_PGTABLES 208f163977dSChristoph Hellwig default 2 209f163977dSChristoph Hellwig 21006503870SJohannes Bergconfig UML_TIME_TRAVEL_SUPPORT 21106503870SJohannes Berg bool 21206503870SJohannes Berg prompt "Support time-travel mode (e.g. for test execution)" 213d65197adSJohannes Berg # inf-cpu mode is incompatible with the benchmarking 214d65197adSJohannes Berg depends on !RAID6_PQ_BENCHMARK 2154b786e24SJohannes Berg depends on !SMP 21606503870SJohannes Berg help 21706503870SJohannes Berg Enable this option to support time travel inside the UML instance. 21806503870SJohannes Berg 21906503870SJohannes Berg After enabling this option, two modes are accessible at runtime 22006503870SJohannes Berg (selected by the kernel command line), see the kernel's command- 22106503870SJohannes Berg line help for more details. 22206503870SJohannes Berg 22306503870SJohannes Berg It is safe to say Y, but you probably don't need this. 22406503870SJohannes Berg 2255b301409SPatricia Alfonsoconfig KASAN_SHADOW_OFFSET 2265b301409SPatricia Alfonso hex 2275b301409SPatricia Alfonso depends on KASAN 2285b301409SPatricia Alfonso default 0x100000000000 2295b301409SPatricia Alfonso help 2305b301409SPatricia Alfonso This is the offset at which the ~16TB of shadow memory is 2315b301409SPatricia Alfonso mapped and used by KASAN for memory debugging. This can be any 2325b301409SPatricia Alfonso address that has at least KASAN_SHADOW_SIZE (total address space divided 2335b301409SPatricia Alfonso by 8) amount of space so that the KASAN shadow memory does not conflict 2345b301409SPatricia Alfonso with anything. The default is 0x100000000000, which works even if mem is 2355b301409SPatricia Alfonso set to a large value. On low-memory systems, try 0x7fff8000, as it fits 2365b301409SPatricia Alfonso into the immediate of most instructions, improving performance. 2375b301409SPatricia Alfonso 238f163977dSChristoph Hellwigendmenu 239f163977dSChristoph Hellwig 2409bea1801SChristoph Hellwigsource "arch/um/drivers/Kconfig" 24192dcd3d3SJohannes Berg 24292dcd3d3SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 24392dcd3d3SJohannes Berg def_bool y 24492dcd3d3SJohannes Berg 24592dcd3d3SJohannes Bergsource "kernel/power/Kconfig" 246