| config DEFCONFIG_LIST |
| string |
| depends on !UML |
| option defconfig_list |
| default "/lib/modules/$UNAME_RELEASE/.config" |
| default "/etc/kernel-config" |
| default "/boot/config-$UNAME_RELEASE" |
| default "arch/$ARCH/defconfig" |
| |
| menu "Code maturity level options" |
| |
| config EXPERIMENTAL |
| bool "Prompt for development and/or incomplete code/drivers" |
| ---help--- |
| Some of the various things that Linux supports (such as network |
| drivers, file systems, network protocols, etc.) can be in a state |
| of development where the functionality, stability, or the level of |
| testing is not yet high enough for general use. This is usually |
| known as the "alpha-test" phase among developers. If a feature is |
| currently in alpha-test, then the developers usually discourage |
| uninformed widespread use of this feature by the general public to |
| avoid "Why doesn't this work?" type mail messages. However, active |
| testing and use of these systems is welcomed. Just be aware that it |
| may not meet the normal level of reliability or it may fail to work |
| in some special cases. Detailed bug reports from people familiar |
| with the kernel internals are usually welcomed by the developers |
| (before submitting bug reports, please read the documents |
| <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>, |
| <file:Documentation/BUG-HUNTING>, and |
| <file:Documentation/oops-tracing.txt> in the kernel source). |
| |
| This option will also make obsoleted drivers available. These are |
| drivers that have been replaced by something else, and/or are |
| scheduled to be removed in a future kernel release. |
| |
| Unless you intend to help test and develop a feature or driver that |
| falls into this category, or you have a situation that requires |
| using these features, you should probably say N here, which will |
| cause the configurator to present you with fewer choices. If |
| you say Y here, you will be offered the choice of using features or |
| drivers that are currently considered to be in the alpha-test phase. |
| |
| config BROKEN |
| bool |
| |
| config BROKEN_ON_SMP |
| bool |
| depends on BROKEN || !SMP |
| default y |
| |
| config LOCK_KERNEL |
| bool |
| depends on SMP || PREEMPT |
| default y |
| |
| config INIT_ENV_ARG_LIMIT |
| int |
| default 32 if !UML |
| default 128 if UML |
| help |
| Maximum of each of the number of arguments and environment |
| variables passed to init from the kernel command line. |
| |
| endmenu |
| |
| menu "General setup" |
| |
| config LOCALVERSION |
| string "Local version - append to kernel release" |
| help |
| Append an extra string to the end of your kernel version. |
| This will show up when you type uname, for example. |
| The string you set here will be appended after the contents of |
| any files with a filename matching localversion* in your |
| object and source tree, in that order. Your total string can |
| be a maximum of 64 characters. |
| |
| config LOCALVERSION_AUTO |
| bool "Automatically append version information to the version string" |
| default y |
| help |
| This will try to automatically determine if the current tree is a |
| release tree by looking for git tags that belong to the current |
| top of tree revision. |
| |
| A string of the format -gxxxxxxxx will be added to the localversion |
| if a git-based tree is found. The string generated by this will be |
| appended after any matching localversion* files, and after the value |
| set in CONFIG_LOCALVERSION. |
| |
| (The actual string used here is the first eight characters produced |
| by running the command: |
| |
| $ git rev-parse --verify HEAD |
| |
| which is done within the script "scripts/setlocalversion".) |
| |
| config SWAP |
| bool "Support for paging of anonymous memory (swap)" |
| depends on MMU && BLOCK |
| default y |
| help |
| This option allows you to choose whether you want to have support |
| for so called swap devices or swap files in your kernel that are |
| used to provide more virtual memory than the actual RAM present |
| in your computer. If unsure say Y. |
| |
| config SYSVIPC |
| bool "System V IPC" |
| ---help--- |
| Inter Process Communication is a suite of library functions and |
| system calls which let processes (running programs) synchronize and |
| exchange information. It is generally considered to be a good thing, |
| and some programs won't run unless you say Y here. In particular, if |
| you want to run the DOS emulator dosemu under Linux (read the |
| DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>), |
| you'll need to say Y here. |
| |
| You can find documentation about IPC with "info ipc" and also in |
| section 6.4 of the Linux Programmer's Guide, available from |
| <http://www.tldp.org/guides.html>. |
| |
| config IPC_NS |
| bool "IPC Namespaces" |
| depends on SYSVIPC |
| default n |
| help |
| Support ipc namespaces. This allows containers, i.e. virtual |
| environments, to use ipc namespaces to provide different ipc |
| objects for different servers. If unsure, say N. |
| |
| config SYSVIPC_SYSCTL |
| bool |
| depends on SYSVIPC |
| depends on SYSCTL |
| default y |
| |
| config POSIX_MQUEUE |
| bool "POSIX Message Queues" |
| depends on NET && EXPERIMENTAL |
| ---help--- |
| POSIX variant of message queues is a part of IPC. In POSIX message |
| queues every message has a priority which decides about succession |
| of receiving it by a process. If you want to compile and run |
| programs written e.g. for Solaris with use of its POSIX message |
| queues (functions mq_*) say Y here. |
| |
| POSIX message queues are visible as a filesystem called 'mqueue' |
| and can be mounted somewhere if you want to do filesystem |
| operations on message queues. |
| |
| If unsure, say Y. |
| |
| config BSD_PROCESS_ACCT |
| bool "BSD Process Accounting" |
| help |
| If you say Y here, a user level program will be able to instruct the |
| kernel (via a special system call) to write process accounting |
| information to a file: whenever a process exits, information about |
| that process will be appended to the file by the kernel. The |
| information includes things such as creation time, owning user, |
| command name, memory usage, controlling terminal etc. (the complete |
| list is in the struct acct in <file:include/linux/acct.h>). It is |
| up to the user level program to do useful things with this |
| information. This is generally a good idea, so say Y. |
| |
| config BSD_PROCESS_ACCT_V3 |
| bool "BSD Process Accounting version 3 file format" |
| depends on BSD_PROCESS_ACCT |
| default n |
| help |
| If you say Y here, the process accounting information is written |
| in a new file format that also logs the process IDs of each |
| process and it's parent. Note that this file format is incompatible |
| with previous v0/v1/v2 file formats, so you will need updated tools |
| for processing it. A preliminary version of these tools is available |
| at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>. |
| |
| config TASKSTATS |
| bool "Export task/process statistics through netlink (EXPERIMENTAL)" |
| depends on NET |
| default n |
| help |
| Export selected statistics for tasks/processes through the |
| generic netlink interface. Unlike BSD process accounting, the |
| statistics are available during the lifetime of tasks/processes as |
| responses to commands. Like BSD accounting, they are sent to user |
| space on task exit. |
| |
| Say N if unsure. |
| |
| config TASK_DELAY_ACCT |
| bool "Enable per-task delay accounting (EXPERIMENTAL)" |
| depends on TASKSTATS |
| help |
| Collect information on time spent by a task waiting for system |
| resources like cpu, synchronous block I/O completion and swapping |
| in pages. Such statistics can help in setting a task's priorities |
| relative to other tasks for cpu, io, rss limits etc. |
| |
| Say N if unsure. |
| |
| config TASK_XACCT |
| bool "Enable extended accounting over taskstats (EXPERIMENTAL)" |
| depends on TASKSTATS |
| help |
| Collect extended task accounting data and send the data |
| to userland for processing over the taskstats interface. |
| |
| Say N if unsure. |
| |
| config TASK_IO_ACCOUNTING |
| bool "Enable per-task storage I/O accounting (EXPERIMENTAL)" |
| depends on TASK_XACCT |
| help |
| Collect information on the number of bytes of storage I/O which this |
| task has caused. |
| |
| Say N if unsure. |
| |
| config UTS_NS |
| bool "UTS Namespaces" |
| default n |
| help |
| Support uts namespaces. This allows containers, i.e. |
| vservers, to use uts namespaces to provide different |
| uts info for different servers. If unsure, say N. |
| |
| config AUDIT |
| bool "Auditing support" |
| depends on NET |
| help |
| Enable auditing infrastructure that can be used with another |
| kernel subsystem, such as SELinux (which requires this for |
| logging of avc messages output). Does not do system-call |
| auditing without CONFIG_AUDITSYSCALL. |
| |
| config AUDITSYSCALL |
| bool "Enable system-call auditing support" |
| depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64) |
| default y if SECURITY_SELINUX |
| help |
| Enable low-overhead system-call auditing infrastructure that |
| can be used independently or with another kernel subsystem, |
| such as SELinux. To use audit's filesystem watch feature, please |
| ensure that INOTIFY is configured. |
| |
| config IKCONFIG |
| tristate "Kernel .config support" |
| ---help--- |
| This option enables the complete Linux kernel ".config" file |
| contents to be saved in the kernel. It provides documentation |
| of which kernel options are used in a running kernel or in an |
| on-disk kernel. This information can be extracted from the kernel |
| image file with the script scripts/extract-ikconfig and used as |
| input to rebuild the current kernel or to build another kernel. |
| It can also be extracted from a running kernel by reading |
| /proc/config.gz if enabled (below). |
| |
| config IKCONFIG_PROC |
| bool "Enable access to .config through /proc/config.gz" |
| depends on IKCONFIG && PROC_FS |
| ---help--- |
| This option enables access to the kernel configuration file |
| through /proc/config.gz. |
| |
| config LOG_BUF_SHIFT |
| int "Kernel log buffer size (16 => 64KB, 17 => 128KB)" |
| range 12 21 |
| default 17 if S390 || LOCKDEP |
| default 16 if X86_NUMAQ || IA64 |
| default 15 if SMP |
| default 14 |
| help |
| Select kernel log buffer size as a power of 2. |
| Defaults and Examples: |
| 17 => 128 KB for S/390 |
| 16 => 64 KB for x86 NUMAQ or IA-64 |
| 15 => 32 KB for SMP |
| 14 => 16 KB for uniprocessor |
| 13 => 8 KB |
| 12 => 4 KB |
| |
| config CPUSETS |
| bool "Cpuset support" |
| depends on SMP |
| help |
| This option will let you create and manage CPUSETs which |
| allow dynamically partitioning a system into sets of CPUs and |
| Memory Nodes and assigning tasks to run only within those sets. |
| This is primarily useful on large SMP or NUMA systems. |
| |
| Say N if unsure. |
| |
| config SYSFS_DEPRECATED |
| bool "Create deprecated sysfs files" |
| default y |
| help |
| This option creates deprecated symlinks such as the |
| "device"-link, the <subsystem>:<name>-link, and the |
| "bus"-link. It may also add deprecated key in the |
| uevent environment. |
| None of these features or values should be used today, as |
| they export driver core implementation details to userspace |
| or export properties which can't be kept stable across kernel |
| releases. |
| |
| If enabled, this option will also move any device structures |
| that belong to a class, back into the /sys/class hierarchy, in |
| order to support older versions of udev. |
| |
| If you are using a distro that was released in 2006 or later, |
| it should be safe to say N here. |
| |
| config RELAY |
| bool "Kernel->user space relay support (formerly relayfs)" |
| help |
| This option enables support for relay interface support in |
| certain file systems (such as debugfs). |
| It is designed to provide an efficient mechanism for tools and |
| facilities to relay large amounts of data from kernel space to |
| user space. |
| |
| If unsure, say N. |
| |
| config BLK_DEV_INITRD |
| bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support" |
| depends on BROKEN || !FRV |
| help |
| The initial RAM filesystem is a ramfs which is loaded by the |
| boot loader (loadlin or lilo) and that is mounted as root |
| before the normal boot procedure. It is typically used to |
| load modules needed to mount the "real" root file system, |
| etc. See <file:Documentation/initrd.txt> for details. |
| |
| If RAM disk support (BLK_DEV_RAM) is also included, this |
| also enables initial RAM disk (initrd) support and adds |
| 15 Kbytes (more on some other architectures) to the kernel size. |
| |
| If unsure say Y. |
| |
| if BLK_DEV_INITRD |
| |
| source "usr/Kconfig" |
| |
| endif |
| |
| config CC_OPTIMIZE_FOR_SIZE |
| bool "Optimize for size (Look out for broken compilers!)" |
| default y |
| depends on ARM || H8300 || EXPERIMENTAL |
| help |
| Enabling this option will pass "-Os" instead of "-O2" to gcc |
| resulting in a smaller kernel. |
| |
| WARNING: some versions of gcc may generate incorrect code with this |
| option. If problems are observed, a gcc upgrade may be needed. |
| |
| If unsure, say N. |
| |
| config SYSCTL |
| bool |
| |
| menuconfig EMBEDDED |
| bool "Configure standard kernel features (for small systems)" |
| help |
| This option allows certain base kernel options and settings |
| to be disabled or tweaked. This is for specialized |
| environments which can tolerate a "non-standard" kernel. |
| Only use this if you really know what you are doing. |
| |
| config UID16 |
| bool "Enable 16-bit UID system calls" if EMBEDDED |
| depends on ARM || BFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION) |
| default y |
| help |
| This enables the legacy 16-bit UID syscall wrappers. |
| |
| config SYSCTL_SYSCALL |
| bool "Sysctl syscall support" if EMBEDDED |
| default y |
| select SYSCTL |
| ---help--- |
| sys_sysctl uses binary paths that have been found challenging |
| to properly maintain and use. The interface in /proc/sys |
| using paths with ascii names is now the primary path to this |
| information. |
| |
| Almost nothing using the binary sysctl interface so if you are |
| trying to save some space it is probably safe to disable this, |
| making your kernel marginally smaller. |
| |
| If unsure say Y here. |
| |
| config KALLSYMS |
| bool "Load all symbols for debugging/ksymoops" if EMBEDDED |
| default y |
| help |
| Say Y here to let the kernel print out symbolic crash information and |
| symbolic stack backtraces. This increases the size of the kernel |
| somewhat, as all symbols have to be loaded into the kernel image. |
| |
| config KALLSYMS_ALL |
| bool "Include all symbols in kallsyms" |
| depends on DEBUG_KERNEL && KALLSYMS |
| help |
| Normally kallsyms only contains the symbols of functions, for nicer |
| OOPS messages. Some debuggers can use kallsyms for other |
| symbols too: say Y here to include all symbols, if you need them |
| and you don't care about adding 300k to the size of your kernel. |
| |
| Say N. |
| |
| config KALLSYMS_EXTRA_PASS |
| bool "Do an extra kallsyms pass" |
| depends on KALLSYMS |
| help |
| If kallsyms is not working correctly, the build will fail with |
| inconsistent kallsyms data. If that occurs, log a bug report and |
| turn on KALLSYMS_EXTRA_PASS which should result in a stable build. |
| Always say N here unless you find a bug in kallsyms, which must be |
| reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while |
| you wait for kallsyms to be fixed. |
| |
| |
| config HOTPLUG |
| bool "Support for hot-pluggable devices" if EMBEDDED |
| default y |
| help |
| This option is provided for the case where no hotplug or uevent |
| capabilities is wanted by the kernel. You should only consider |
| disabling this option for embedded systems that do not use modules, a |
| dynamic /dev tree, or dynamic device discovery. Just say Y. |
| |
| config PRINTK |
| default y |
| bool "Enable support for printk" if EMBEDDED |
| help |
| This option enables normal printk support. Removing it |
| eliminates most of the message strings from the kernel image |
| and makes the kernel more or less silent. As this makes it |
| very difficult to diagnose system problems, saying N here is |
| strongly discouraged. |
| |
| config BUG |
| bool "BUG() support" if EMBEDDED |
| default y |
| help |
| Disabling this option eliminates support for BUG and WARN, reducing |
| the size of your kernel image and potentially quietly ignoring |
| numerous fatal conditions. You should only consider disabling this |
| option for embedded systems with no facilities for reporting errors. |
| Just say Y. |
| |
| config ELF_CORE |
| default y |
| bool "Enable ELF core dumps" if EMBEDDED |
| help |
| Enable support for generating core dumps. Disabling saves about 4k. |
| |
| config BASE_FULL |
| default y |
| bool "Enable full-sized data structures for core" if EMBEDDED |
| help |
| Disabling this option reduces the size of miscellaneous core |
| kernel data structures. This saves memory on small machines, |
| but may reduce performance. |
| |
| config FUTEX |
| bool "Enable futex support" if EMBEDDED |
| default y |
| select RT_MUTEXES |
| help |
| Disabling this option will cause the kernel to be built without |
| support for "fast userspace mutexes". The resulting kernel may not |
| run glibc-based applications correctly. |
| |
| config ANON_INODES |
| bool "Enable anonymous inode source" if EMBEDDED |
| default y |
| help |
| Anonymous inode source for pseudo-files like epoll, signalfd, |
| timerfd and eventfd. |
| |
| If unsure, say Y. |
| |
| config EPOLL |
| bool "Enable eventpoll support" if EMBEDDED |
| default y |
| depends on ANON_INODES |
| help |
| Disabling this option will cause the kernel to be built without |
| support for epoll family of system calls. |
| |
| config SIGNALFD |
| bool "Enable signalfd() system call" if EMBEDDED |
| depends on ANON_INODES |
| default y |
| help |
| Enable the signalfd() system call that allows to receive signals |
| on a file descriptor. |
| |
| If unsure, say Y. |
| |
| config TIMERFD |
| bool "Enable timerfd() system call" if EMBEDDED |
| depends on ANON_INODES |
| default y |
| help |
| Enable the timerfd() system call that allows to receive timer |
| events on a file descriptor. |
| |
| If unsure, say Y. |
| |
| config EVENTFD |
| bool "Enable eventfd() system call" if EMBEDDED |
| depends on ANON_INODES |
| default y |
| help |
| Enable the eventfd() system call that allows to receive both |
| kernel notification (ie. KAIO) or userspace notifications. |
| |
| If unsure, say Y. |
| |
| config SHMEM |
| bool "Use full shmem filesystem" if EMBEDDED |
| default y |
| depends on MMU |
| help |
| The shmem is an internal filesystem used to manage shared memory. |
| It is backed by swap and manages resource limits. It is also exported |
| to userspace as tmpfs if TMPFS is enabled. Disabling this |
| option replaces shmem and tmpfs with the much simpler ramfs code, |
| which may be appropriate on small systems without swap. |
| |
| config VM_EVENT_COUNTERS |
| default y |
| bool "Enable VM event counters for /proc/vmstat" if EMBEDDED |
| help |
| VM event counters are needed for event counts to be shown. |
| This option allows the disabling of the VM event counters |
| on EMBEDDED systems. /proc/vmstat will only show page counts |
| if VM event counters are disabled. |
| |
| config SLUB_DEBUG |
| default y |
| bool "Enable SLUB debugging support" if EMBEDDED |
| depends on SLUB |
| help |
| SLUB has extensive debug support features. Disabling these can |
| result in significant savings in code size. This also disables |
| SLUB sysfs support. /sys/slab will not exist and there will be |
| no support for cache validation etc. |
| |
| choice |
| prompt "Choose SLAB allocator" |
| default SLAB |
| help |
| This option allows to select a slab allocator. |
| |
| config SLAB |
| bool "SLAB" |
| help |
| The regular slab allocator that is established and known to work |
| well in all environments. It organizes cache hot objects in |
| per cpu and per node queues. SLAB is the default choice for |
| a slab allocator. |
| |
| config SLUB |
| depends on EXPERIMENTAL && !ARCH_USES_SLAB_PAGE_STRUCT |
| bool "SLUB (Unqueued Allocator)" |
| help |
| SLUB is a slab allocator that minimizes cache line usage |
| instead of managing queues of cached objects (SLAB approach). |
| Per cpu caching is realized using slabs of objects instead |
| of queues of objects. SLUB can use memory efficiently |
| and has enhanced diagnostics. |
| |
| config SLOB |
| depends on EMBEDDED && !SPARSEMEM |
| bool "SLOB (Simple Allocator)" |
| help |
| SLOB replaces the SLAB allocator with a drastically simpler |
| allocator. SLOB is more space efficient than SLAB but does not |
| scale well (single lock for all operations) and is also highly |
| susceptible to fragmentation. SLUB can accomplish a higher object |
| density. It is usually better to use SLUB instead of SLOB. |
| |
| endchoice |
| |
| endmenu # General setup |
| |
| config RT_MUTEXES |
| boolean |
| select PLIST |
| |
| config TINY_SHMEM |
| default !SHMEM |
| bool |
| |
| config BASE_SMALL |
| int |
| default 0 if BASE_FULL |
| default 1 if !BASE_FULL |
| |
| menu "Loadable module support" |
| |
| config MODULES |
| bool "Enable loadable module support" |
| help |
| Kernel modules are small pieces of compiled code which can |
| be inserted in the running kernel, rather than being |
| permanently built into the kernel. You use the "modprobe" |
| tool to add (and sometimes remove) them. If you say Y here, |
| many parts of the kernel can be built as modules (by |
| answering M instead of Y where indicated): this is most |
| useful for infrequently used options which are not required |
| for booting. For more information, see the man pages for |
| modprobe, lsmod, modinfo, insmod and rmmod. |
| |
| If you say Y here, you will need to run "make |
| modules_install" to put the modules under /lib/modules/ |
| where modprobe can find them (you may need to be root to do |
| this). |
| |
| If unsure, say Y. |
| |
| config MODULE_UNLOAD |
| bool "Module unloading" |
| depends on MODULES |
| help |
| Without this option you will not be able to unload any |
| modules (note that some modules may not be unloadable |
| anyway), which makes your kernel slightly smaller and |
| simpler. If unsure, say Y. |
| |
| config MODULE_FORCE_UNLOAD |
| bool "Forced module unloading" |
| depends on MODULE_UNLOAD && EXPERIMENTAL |
| help |
| This option allows you to force a module to unload, even if the |
| kernel believes it is unsafe: the kernel will remove the module |
| without waiting for anyone to stop using it (using the -f option to |
| rmmod). This is mainly for kernel developers and desperate users. |
| If unsure, say N. |
| |
| config MODVERSIONS |
| bool "Module versioning support" |
| depends on MODULES |
| help |
| Usually, you have to use modules compiled with your kernel. |
| Saying Y here makes it sometimes possible to use modules |
| compiled for different kernels, by adding enough information |
| to the modules to (hopefully) spot any changes which would |
| make them incompatible with the kernel you are running. If |
| unsure, say N. |
| |
| config MODULE_SRCVERSION_ALL |
| bool "Source checksum for all modules" |
| depends on MODULES |
| help |
| Modules which contain a MODULE_VERSION get an extra "srcversion" |
| field inserted into their modinfo section, which contains a |
| sum of the source files which made it. This helps maintainers |
| see exactly which source was used to build a module (since |
| others sometimes change the module source without updating |
| the version). With this option, such a "srcversion" field |
| will be created for all modules. If unsure, say N. |
| |
| config KMOD |
| bool "Automatic kernel module loading" |
| depends on MODULES |
| help |
| Normally when you have selected some parts of the kernel to |
| be created as kernel modules, you must load them (using the |
| "modprobe" command) before you can use them. If you say Y |
| here, some parts of the kernel will be able to load modules |
| automatically: when a part of the kernel needs a module, it |
| runs modprobe with the appropriate arguments, thereby |
| loading the module if it is available. If unsure, say Y. |
| |
| config STOP_MACHINE |
| bool |
| default y |
| depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU |
| help |
| Need stop_machine() primitive. |
| endmenu |
| |
| menu "Block layer" |
| source "block/Kconfig" |
| endmenu |