| config ARCH | 
 | 	string | 
 | 	option env="ARCH" | 
 |  | 
 | config KERNELVERSION | 
 | 	string | 
 | 	option env="KERNELVERSION" | 
 |  | 
 | 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 "$ARCH_DEFCONFIG" | 
 | 	default "arch/$ARCH/defconfig" | 
 |  | 
 | menu "General setup" | 
 |  | 
 | 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 | 	  drivers that have been replaced by something else, and/or are | 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. | 
 |  | 
 |  | 
 | 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 HAVE_KERNEL_GZIP | 
 | 	bool | 
 |  | 
 | config HAVE_KERNEL_BZIP2 | 
 | 	bool | 
 |  | 
 | config HAVE_KERNEL_LZMA | 
 | 	bool | 
 |  | 
 | choice | 
 | 	prompt "Kernel compression mode" | 
 | 	default KERNEL_GZIP | 
 | 	depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA | 
 | 	help | 
 | 	  The linux kernel is a kind of self-extracting executable. | 
 | 	  Several compression algorithms are available, which differ | 
 | 	  in efficiency, compression and decompression speed. | 
 | 	  Compression speed is only relevant when building a kernel. | 
 | 	  Decompression speed is relevant at each boot. | 
 |  | 
 | 	  If you have any problems with bzip2 or lzma compressed | 
 | 	  kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older | 
 | 	  version of this functionality (bzip2 only), for 2.4, was | 
 | 	  supplied by Christian Ludwig) | 
 |  | 
 | 	  High compression options are mostly useful for users, who | 
 | 	  are low on disk space (embedded systems), but for whom ram | 
 | 	  size matters less. | 
 |  | 
 | 	  If in doubt, select 'gzip' | 
 |  | 
 | config KERNEL_GZIP | 
 | 	bool "Gzip" | 
 | 	depends on HAVE_KERNEL_GZIP | 
 | 	help | 
 | 	  The old and tried gzip compression. Its compression ratio is | 
 | 	  the poorest among the 3 choices; however its speed (both | 
 | 	  compression and decompression) is the fastest. | 
 |  | 
 | config KERNEL_BZIP2 | 
 | 	bool "Bzip2" | 
 | 	depends on HAVE_KERNEL_BZIP2 | 
 | 	help | 
 | 	  Its compression ratio and speed is intermediate. | 
 | 	  Decompression speed is slowest among the three.  The kernel | 
 | 	  size is about 10% smaller with bzip2, in comparison to gzip. | 
 | 	  Bzip2 uses a large amount of memory. For modern kernels you | 
 | 	  will need at least 8MB RAM or more for booting. | 
 |  | 
 | config KERNEL_LZMA | 
 | 	bool "LZMA" | 
 | 	depends on HAVE_KERNEL_LZMA | 
 | 	help | 
 | 	  The most recent compression algorithm. | 
 | 	  Its ratio is best, decompression speed is between the other | 
 | 	  two. Compression is slowest.	The kernel size is about 33% | 
 | 	  smaller with LZMA in comparison to gzip. | 
 |  | 
 | endchoice | 
 |  | 
 | 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 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 POSIX_MQUEUE_SYSCTL | 
 | 	bool | 
 | 	depends on POSIX_MQUEUE | 
 | 	depends on SYSCTL | 
 | 	default 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.gnu.org/software/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 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|| SUPERH) | 
 | 	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 AUDIT_TREE | 
 | 	def_bool y | 
 | 	depends on AUDITSYSCALL && INOTIFY | 
 |  | 
 | menu "RCU Subsystem" | 
 |  | 
 | choice | 
 | 	prompt "RCU Implementation" | 
 | 	default CLASSIC_RCU | 
 |  | 
 | config CLASSIC_RCU | 
 | 	bool "Classic RCU" | 
 | 	help | 
 | 	  This option selects the classic RCU implementation that is | 
 | 	  designed for best read-side performance on non-realtime | 
 | 	  systems. | 
 |  | 
 | 	  Select this option if you are unsure. | 
 |  | 
 | config TREE_RCU | 
 | 	bool "Tree-based hierarchical RCU" | 
 | 	help | 
 | 	  This option selects the RCU implementation that is | 
 | 	  designed for very large SMP system with hundreds or | 
 | 	  thousands of CPUs. | 
 |  | 
 | config PREEMPT_RCU | 
 | 	bool "Preemptible RCU" | 
 | 	depends on PREEMPT | 
 | 	help | 
 | 	  This option reduces the latency of the kernel by making certain | 
 | 	  RCU sections preemptible. Normally RCU code is non-preemptible, if | 
 | 	  this option is selected then read-only RCU sections become | 
 | 	  preemptible. This helps latency, but may expose bugs due to | 
 | 	  now-naive assumptions about each RCU read-side critical section | 
 | 	  remaining on a given CPU through its execution. | 
 |  | 
 | endchoice | 
 |  | 
 | config RCU_TRACE | 
 | 	bool "Enable tracing for RCU" | 
 | 	depends on TREE_RCU || PREEMPT_RCU | 
 | 	help | 
 | 	  This option provides tracing in RCU which presents stats | 
 | 	  in debugfs for debugging RCU implementation. | 
 |  | 
 | 	  Say Y here if you want to enable RCU tracing | 
 | 	  Say N if you are unsure. | 
 |  | 
 | config RCU_FANOUT | 
 | 	int "Tree-based hierarchical RCU fanout value" | 
 | 	range 2 64 if 64BIT | 
 | 	range 2 32 if !64BIT | 
 | 	depends on TREE_RCU | 
 | 	default 64 if 64BIT | 
 | 	default 32 if !64BIT | 
 | 	help | 
 | 	  This option controls the fanout of hierarchical implementations | 
 | 	  of RCU, allowing RCU to work efficiently on machines with | 
 | 	  large numbers of CPUs.  This value must be at least the cube | 
 | 	  root of NR_CPUS, which allows NR_CPUS up to 32,768 for 32-bit | 
 | 	  systems and up to 262,144 for 64-bit systems. | 
 |  | 
 | 	  Select a specific number if testing RCU itself. | 
 | 	  Take the default if unsure. | 
 |  | 
 | config RCU_FANOUT_EXACT | 
 | 	bool "Disable tree-based hierarchical RCU auto-balancing" | 
 | 	depends on TREE_RCU | 
 | 	default n | 
 | 	help | 
 | 	  This option forces use of the exact RCU_FANOUT value specified, | 
 | 	  regardless of imbalances in the hierarchy.  This is useful for | 
 | 	  testing RCU itself, and might one day be useful on systems with | 
 | 	  strong NUMA behavior. | 
 |  | 
 | 	  Without RCU_FANOUT_EXACT, the code will balance the hierarchy. | 
 |  | 
 | 	  Say N if unsure. | 
 |  | 
 | config TREE_RCU_TRACE | 
 | 	def_bool RCU_TRACE && TREE_RCU | 
 | 	select DEBUG_FS | 
 | 	help | 
 | 	  This option provides tracing for the TREE_RCU implementation, | 
 | 	  permitting Makefile to trivially select kernel/rcutree_trace.c. | 
 |  | 
 | config PREEMPT_RCU_TRACE | 
 | 	def_bool RCU_TRACE && PREEMPT_RCU | 
 | 	select DEBUG_FS | 
 | 	help | 
 | 	  This option provides tracing for the PREEMPT_RCU implementation, | 
 | 	  permitting Makefile to trivially select kernel/rcupreempt_trace.c. | 
 |  | 
 | endmenu # "RCU Subsystem" | 
 |  | 
 | 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 | 
 | 	help | 
 | 	  Select kernel log buffer size as a power of 2. | 
 | 	  Examples: | 
 | 	  	     17 => 128 KB | 
 | 		     16 => 64 KB | 
 | 	             15 => 32 KB | 
 | 	             14 => 16 KB | 
 | 		     13 =>  8 KB | 
 | 		     12 =>  4 KB | 
 |  | 
 | # | 
 | # Architectures with an unreliable sched_clock() should select this: | 
 | # | 
 | config HAVE_UNSTABLE_SCHED_CLOCK | 
 | 	bool | 
 |  | 
 | config GROUP_SCHED | 
 | 	bool "Group CPU scheduler" | 
 | 	depends on EXPERIMENTAL | 
 | 	default n | 
 | 	help | 
 | 	  This feature lets CPU scheduler recognize task groups and control CPU | 
 | 	  bandwidth allocation to such task groups. | 
 | 	  In order to create a group from arbitrary set of processes, use | 
 | 	  CONFIG_CGROUPS. (See Control Group support.) | 
 |  | 
 | config FAIR_GROUP_SCHED | 
 | 	bool "Group scheduling for SCHED_OTHER" | 
 | 	depends on GROUP_SCHED | 
 | 	default GROUP_SCHED | 
 |  | 
 | config RT_GROUP_SCHED | 
 | 	bool "Group scheduling for SCHED_RR/FIFO" | 
 | 	depends on EXPERIMENTAL | 
 | 	depends on GROUP_SCHED | 
 | 	default n | 
 | 	help | 
 | 	  This feature lets you explicitly allocate real CPU bandwidth | 
 | 	  to users or control groups (depending on the "Basis for grouping tasks" | 
 | 	  setting below. If enabled, it will also make it impossible to | 
 | 	  schedule realtime tasks for non-root users until you allocate | 
 | 	  realtime bandwidth for them. | 
 | 	  See Documentation/scheduler/sched-rt-group.txt for more information. | 
 |  | 
 | choice | 
 | 	depends on GROUP_SCHED | 
 | 	prompt "Basis for grouping tasks" | 
 | 	default USER_SCHED | 
 |  | 
 | config USER_SCHED | 
 | 	bool "user id" | 
 | 	help | 
 | 	  This option will choose userid as the basis for grouping | 
 | 	  tasks, thus providing equal CPU bandwidth to each user. | 
 |  | 
 | config CGROUP_SCHED | 
 | 	bool "Control groups" | 
 |  	depends on CGROUPS | 
 |  	help | 
 | 	  This option allows you to create arbitrary task groups | 
 | 	  using the "cgroup" pseudo filesystem and control | 
 | 	  the cpu bandwidth allocated to each such task group. | 
 | 	  Refer to Documentation/cgroups/cgroups.txt for more | 
 | 	  information on "cgroup" pseudo filesystem. | 
 |  | 
 | endchoice | 
 |  | 
 | menuconfig CGROUPS | 
 | 	boolean "Control Group support" | 
 | 	help | 
 | 	  This option adds support for grouping sets of processes together, for | 
 | 	  use with process control subsystems such as Cpusets, CFS, memory | 
 | 	  controls or device isolation. | 
 | 	  See | 
 | 		- Documentation/scheduler/sched-design-CFS.txt	(CFS) | 
 | 		- Documentation/cgroups/ (features for grouping, isolation | 
 | 					  and resource control) | 
 |  | 
 | 	  Say N if unsure. | 
 |  | 
 | if CGROUPS | 
 |  | 
 | config CGROUP_DEBUG | 
 | 	bool "Example debug cgroup subsystem" | 
 | 	depends on CGROUPS | 
 | 	default n | 
 | 	help | 
 | 	  This option enables a simple cgroup subsystem that | 
 | 	  exports useful debugging information about the cgroups | 
 | 	  framework. | 
 |  | 
 | 	  Say N if unsure. | 
 |  | 
 | config CGROUP_NS | 
 | 	bool "Namespace cgroup subsystem" | 
 | 	depends on CGROUPS | 
 | 	help | 
 | 	  Provides a simple namespace cgroup subsystem to | 
 | 	  provide hierarchical naming of sets of namespaces, | 
 | 	  for instance virtual servers and checkpoint/restart | 
 | 	  jobs. | 
 |  | 
 | config CGROUP_FREEZER | 
 | 	bool "Freezer cgroup subsystem" | 
 | 	depends on CGROUPS | 
 | 	help | 
 | 	  Provides a way to freeze and unfreeze all tasks in a | 
 | 	  cgroup. | 
 |  | 
 | config CGROUP_DEVICE | 
 | 	bool "Device controller for cgroups" | 
 | 	depends on CGROUPS && EXPERIMENTAL | 
 | 	help | 
 | 	  Provides a cgroup implementing whitelists for devices which | 
 | 	  a process in the cgroup can mknod or open. | 
 |  | 
 | config CPUSETS | 
 | 	bool "Cpuset support" | 
 | 	depends on CGROUPS | 
 | 	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 PROC_PID_CPUSET | 
 | 	bool "Include legacy /proc/<pid>/cpuset file" | 
 | 	depends on CPUSETS | 
 | 	default y | 
 |  | 
 | config CGROUP_CPUACCT | 
 | 	bool "Simple CPU accounting cgroup subsystem" | 
 | 	depends on CGROUPS | 
 | 	help | 
 | 	  Provides a simple Resource Controller for monitoring the | 
 | 	  total CPU consumed by the tasks in a cgroup. | 
 |  | 
 | config RESOURCE_COUNTERS | 
 | 	bool "Resource counters" | 
 | 	help | 
 | 	  This option enables controller independent resource accounting | 
 | 	  infrastructure that works with cgroups. | 
 | 	depends on CGROUPS | 
 |  | 
 | config CGROUP_MEM_RES_CTLR | 
 | 	bool "Memory Resource Controller for Control Groups" | 
 | 	depends on CGROUPS && RESOURCE_COUNTERS | 
 | 	select MM_OWNER | 
 | 	help | 
 | 	  Provides a memory resource controller that manages both anonymous | 
 | 	  memory and page cache. (See Documentation/cgroups/memory.txt) | 
 |  | 
 | 	  Note that setting this option increases fixed memory overhead | 
 | 	  associated with each page of memory in the system. By this, | 
 | 	  20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory | 
 | 	  usage tracking struct at boot. Total amount of this is printed out | 
 | 	  at boot. | 
 |  | 
 | 	  Only enable when you're ok with these trade offs and really | 
 | 	  sure you need the memory resource controller. Even when you enable | 
 | 	  this, you can set "cgroup_disable=memory" at your boot option to | 
 | 	  disable memory resource controller and you can avoid overheads. | 
 | 	  (and lose benefits of memory resource controller) | 
 |  | 
 | 	  This config option also selects MM_OWNER config option, which | 
 | 	  could in turn add some fork/exit overhead. | 
 |  | 
 | config CGROUP_MEM_RES_CTLR_SWAP | 
 | 	bool "Memory Resource Controller Swap Extension(EXPERIMENTAL)" | 
 | 	depends on CGROUP_MEM_RES_CTLR && SWAP && EXPERIMENTAL | 
 | 	help | 
 | 	  Add swap management feature to memory resource controller. When you | 
 | 	  enable this, you can limit mem+swap usage per cgroup. In other words, | 
 | 	  when you disable this, memory resource controller has no cares to | 
 | 	  usage of swap...a process can exhaust all of the swap. This extension | 
 | 	  is useful when you want to avoid exhaustion swap but this itself | 
 | 	  adds more overheads and consumes memory for remembering information. | 
 | 	  Especially if you use 32bit system or small memory system, please | 
 | 	  be careful about enabling this. When memory resource controller | 
 | 	  is disabled by boot option, this will be automatically disabled and | 
 | 	  there will be no overhead from this. Even when you set this config=y, | 
 | 	  if boot option "noswapaccount" is set, swap will not be accounted. | 
 | 	  Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page | 
 | 	  size is 4096bytes, 512k per 1Gbytes of swap. | 
 |  | 
 | endif # CGROUPS | 
 |  | 
 | config MM_OWNER | 
 | 	bool | 
 |  | 
 | config SYSFS_DEPRECATED | 
 | 	bool | 
 |  | 
 | config SYSFS_DEPRECATED_V2 | 
 | 	bool "Create deprecated sysfs layout for older userspace tools" | 
 | 	depends on SYSFS | 
 | 	default y | 
 | 	select SYSFS_DEPRECATED | 
 | 	help | 
 | 	  This option switches the layout of sysfs to the deprecated | 
 | 	  version. | 
 |  | 
 | 	  The current sysfs layout features a unified device tree at | 
 | 	  /sys/devices/, which is able to express a hierarchy between | 
 | 	  class devices. If the deprecated option is set to Y, the | 
 | 	  unified device tree is split into a bus device tree at | 
 | 	  /sys/devices/ and several individual class device trees at | 
 | 	  /sys/class/. The class and bus devices will be connected by | 
 | 	  "<subsystem>:<name>" and the "device" links. The "block" | 
 | 	  class devices, will not show up in /sys/class/block/. Some | 
 | 	  subsystems will suppress the creation of some devices which | 
 | 	  depend on the unified device tree. | 
 |  | 
 | 	  This option is not a pure compatibility option that can | 
 | 	  be safely enabled on newer distributions. It will change the | 
 | 	  layout of sysfs to the non-extensible deprecated version, | 
 | 	  and disable some features, which can not be exported without | 
 | 	  confusing older userspace tools. Since 2007/2008 all major | 
 | 	  distributions do not enable this option, and ship no tools which | 
 | 	  depend on the deprecated layout or this option. | 
 |  | 
 | 	  If you are using a new kernel on an older distribution, or use | 
 | 	  older userspace tools, you might need to say Y here. Do not say Y, | 
 | 	  if the original kernel, that came with your distribution, has | 
 | 	  this option set to N. | 
 |  | 
 | 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 NAMESPACES | 
 | 	bool "Namespaces support" if EMBEDDED | 
 | 	default !EMBEDDED | 
 | 	help | 
 | 	  Provides the way to make tasks work with different objects using | 
 | 	  the same id. For example same IPC id may refer to different objects | 
 | 	  or same user id or pid may refer to different tasks when used in | 
 | 	  different namespaces. | 
 |  | 
 | config UTS_NS | 
 | 	bool "UTS namespace" | 
 | 	depends on NAMESPACES | 
 | 	help | 
 | 	  In this namespace tasks see different info provided with the | 
 | 	  uname() system call | 
 |  | 
 | config IPC_NS | 
 | 	bool "IPC namespace" | 
 | 	depends on NAMESPACES && (SYSVIPC || POSIX_MQUEUE) | 
 | 	help | 
 | 	  In this namespace tasks work with IPC ids which correspond to | 
 | 	  different IPC objects in different namespaces. | 
 |  | 
 | config USER_NS | 
 | 	bool "User namespace (EXPERIMENTAL)" | 
 | 	depends on NAMESPACES && EXPERIMENTAL | 
 | 	help | 
 | 	  This allows containers, i.e. vservers, to use user namespaces | 
 | 	  to provide different user info for different servers. | 
 | 	  If unsure, say N. | 
 |  | 
 | config PID_NS | 
 | 	bool "PID Namespaces (EXPERIMENTAL)" | 
 | 	default n | 
 | 	depends on NAMESPACES && EXPERIMENTAL | 
 | 	help | 
 | 	  Support process id namespaces.  This allows having multiple | 
 | 	  processes with the same pid as long as they are in different | 
 | 	  pid namespaces.  This is a building block of containers. | 
 |  | 
 | 	  Unless you want to work with an experimental feature | 
 | 	  say N here. | 
 |  | 
 | config NET_NS | 
 | 	bool "Network namespace" | 
 | 	default n | 
 | 	depends on NAMESPACES && EXPERIMENTAL && NET | 
 | 	help | 
 | 	  Allow user space to create what appear to be multiple instances | 
 | 	  of the network stack. | 
 |  | 
 | 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" | 
 | 	default y | 
 | 	help | 
 | 	  Enabling this option will pass "-Os" instead of "-O2" to gcc | 
 | 	  resulting in a smaller kernel. | 
 |  | 
 | 	  If unsure, say Y. | 
 |  | 
 | config SYSCTL | 
 | 	bool | 
 |  | 
 | config ANON_INODES | 
 | 	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 || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && 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 STRIP_ASM_SYMS | 
 | 	bool "Strip assembler-generated symbols during link" | 
 | 	default n | 
 | 	help | 
 | 	  Strip internal assembler-generated symbols during a link (symbols | 
 | 	  that look like '.Lxxx') so they don't pollute the output of | 
 | 	  get_wchan() and suchlike. | 
 |  | 
 | 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 PCSPKR_PLATFORM | 
 | 	bool "Enable PC-Speaker support" if EMBEDDED | 
 | 	depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES | 
 | 	default y | 
 | 	help | 
 |           This option allows to disable the internal PC-Speaker | 
 |           support, saving some memory. | 
 |  | 
 | 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 EPOLL | 
 | 	bool "Enable eventpoll support" if EMBEDDED | 
 | 	default y | 
 | 	select 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 | 
 | 	select 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 | 
 | 	select 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 | 
 | 	select 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 AIO | 
 | 	bool "Enable AIO support" if EMBEDDED | 
 | 	default y | 
 | 	help | 
 | 	  This option enables POSIX asynchronous I/O which may by used | 
 |           by some high performance threaded applications. Disabling | 
 |           this option saves about 7k. | 
 |  | 
 | 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 PCI_QUIRKS | 
 | 	default y | 
 | 	bool "Enable PCI quirk workarounds" if EMBEDDED | 
 | 	depends on PCI | 
 | 	help | 
 | 	  This enables workarounds for various PCI chipset | 
 |           bugs/quirks. Disable this only if your target machine is | 
 |           unaffected by PCI quirks. | 
 |  | 
 | config SLUB_DEBUG | 
 | 	default y | 
 | 	bool "Enable SLUB debugging support" if EMBEDDED | 
 | 	depends on SLUB && SYSFS | 
 | 	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. | 
 |  | 
 | config COMPAT_BRK | 
 | 	bool "Disable heap randomization" | 
 | 	default y | 
 | 	help | 
 | 	  Randomizing heap placement makes heap exploits harder, but it | 
 | 	  also breaks ancient binaries (including anything libc5 based). | 
 | 	  This option changes the bootup default to heap randomization | 
 | 	  disabled, and can be overridden at runtime by setting | 
 | 	  /proc/sys/kernel/randomize_va_space to 2. | 
 |  | 
 | 	  On non-ancient distros (post-2000 ones) N is usually a safe choice. | 
 |  | 
 | choice | 
 | 	prompt "Choose SLAB allocator" | 
 | 	default SLUB | 
 | 	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. | 
 |  | 
 | config SLUB | 
 | 	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. SLUB is the default choice for | 
 | 	   a slab allocator. | 
 |  | 
 | config SLOB | 
 | 	depends on EMBEDDED | 
 | 	bool "SLOB (Simple Allocator)" | 
 | 	help | 
 | 	   SLOB replaces the stock allocator with a drastically simpler | 
 | 	   allocator. SLOB is generally more space efficient but | 
 | 	   does not perform as well on large systems. | 
 |  | 
 | endchoice | 
 |  | 
 | config PROFILING | 
 | 	bool "Profiling support (EXPERIMENTAL)" | 
 | 	help | 
 | 	  Say Y here to enable the extended profiling support mechanisms used | 
 | 	  by profilers such as OProfile. | 
 |  | 
 | # | 
 | # Place an empty function call at each tracepoint site. Can be | 
 | # dynamically changed for a probe function. | 
 | # | 
 | config TRACEPOINTS | 
 | 	bool | 
 |  | 
 | config MARKERS | 
 | 	bool "Activate markers" | 
 | 	select TRACEPOINTS | 
 | 	help | 
 | 	  Place an empty function call at each marker site. Can be | 
 | 	  dynamically changed for a probe function. | 
 |  | 
 | source "arch/Kconfig" | 
 |  | 
 | config SLOW_WORK | 
 | 	default n | 
 | 	bool | 
 | 	help | 
 | 	  The slow work thread pool provides a number of dynamically allocated | 
 | 	  threads that can be used by the kernel to perform operations that | 
 | 	  take a relatively long time. | 
 |  | 
 | 	  An example of this would be CacheFiles doing a path lookup followed | 
 | 	  by a series of mkdirs and a create call, all of which have to touch | 
 | 	  disk. | 
 |  | 
 | 	  See Documentation/slow-work.txt. | 
 |  | 
 | endmenu		# General setup | 
 |  | 
 | config HAVE_GENERIC_DMA_COHERENT | 
 | 	bool | 
 | 	default n | 
 |  | 
 | config SLABINFO | 
 | 	bool | 
 | 	depends on PROC_FS | 
 | 	depends on SLAB || SLUB_DEBUG | 
 | 	default y | 
 |  | 
 | config RT_MUTEXES | 
 | 	boolean | 
 |  | 
 | config BASE_SMALL | 
 | 	int | 
 | 	default 0 if BASE_FULL | 
 | 	default 1 if !BASE_FULL | 
 |  | 
 | menuconfig 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. | 
 |  | 
 | if MODULES | 
 |  | 
 | config MODULE_FORCE_LOAD | 
 | 	bool "Forced module loading" | 
 | 	default n | 
 | 	help | 
 | 	  Allow loading of modules without version information (ie. modprobe | 
 | 	  --force).  Forced module loading sets the 'F' (forced) taint flag and | 
 | 	  is usually a really bad idea. | 
 |  | 
 | config MODULE_UNLOAD | 
 | 	bool "Module unloading" | 
 | 	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 smaller, faster | 
 | 	  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" | 
 | 	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" | 
 | 	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. | 
 |  | 
 | endif # MODULES | 
 |  | 
 | config INIT_ALL_POSSIBLE | 
 | 	bool | 
 | 	help | 
 | 	  Back when each arch used to define their own cpu_online_map and | 
 | 	  cpu_possible_map, some of them chose to initialize cpu_possible_map | 
 | 	  with all 1s, and others with all 0s.  When they were centralised, | 
 | 	  it was better to provide this option than to break all the archs | 
 | 	  and have several arch maintainers pursuing me down dark alleys. | 
 |  | 
 | config STOP_MACHINE | 
 | 	bool | 
 | 	default y | 
 | 	depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU | 
 | 	help | 
 | 	  Need stop_machine() primitive. | 
 |  | 
 | source "block/Kconfig" | 
 |  | 
 | config PREEMPT_NOTIFIERS | 
 | 	bool | 
 |  |