1 # Copyright (C) 2006-2014 OpenWrt.org
3 # This is free software, licensed under the GNU General Public License v2.
4 # See /LICENSE for more information.
7 config KERNEL_BUILD_USER
8 string "Custom Kernel Build User Name"
11 Sets the Kernel build user string, which for example will be returned
12 by 'uname -a' on running systems.
13 If not set, uses system user at build time.
15 config KERNEL_BUILD_DOMAIN
16 string "Custom Kernel Build Domain Name"
19 Sets the Kernel build domain string, which for example will be
20 returned by 'uname -a' on running systems.
21 If not set, uses system hostname at build time.
24 bool "Enable support for printk"
27 config KERNEL_CRASHLOG
29 depends on !(arm || powerpc || sparc || TARGET_uml || i386 || x86_64)
33 bool "Support for paging of anonymous memory (swap)"
36 config KERNEL_DEBUG_FS
37 bool "Compile the kernel with debug filesystem enabled"
40 debugfs is a virtual file system that kernel developers use to put
41 debugging files into. Enable this option to be able to read and
42 write to these files. Many common debugging facilities, such as
43 ftrace, require the existence of debugfs.
48 depends on (arm || arm64)
50 config KERNEL_PERF_EVENTS
53 select KERNEL_ARM_PMU if (arm || arm64)
55 config KERNEL_PROFILING
56 bool "Compile the kernel with profiling enabled"
58 select KERNEL_PERF_EVENTS
60 Enable the extended profiling support mechanisms used by profilers such
63 config KERNEL_KALLSYMS
64 bool "Compile the kernel with symbol table information"
65 default y if !SMALL_FLASH
67 This will give you more information in stack traces from kernel oopses.
70 bool "Compile the kernel with tracing support"
71 depends on !TARGET_uml
74 config KERNEL_FTRACE_SYSCALLS
75 bool "Trace system calls"
76 depends on KERNEL_FTRACE
79 config KERNEL_ENABLE_DEFAULT_TRACERS
80 bool "Trace process context switches and events"
81 depends on KERNEL_FTRACE
84 config KERNEL_FUNCTION_TRACER
85 bool "Function tracer"
86 depends on KERNEL_FTRACE
89 config KERNEL_FUNCTION_GRAPH_TRACER
90 bool "Function graph tracer"
91 depends on KERNEL_FUNCTION_TRACER
94 config KERNEL_DYNAMIC_FTRACE
95 bool "Enable/disable function tracing dynamically"
96 depends on KERNEL_FUNCTION_TRACER
99 config KERNEL_FUNCTION_PROFILER
100 bool "Function profiler"
101 depends on KERNEL_FUNCTION_TRACER
104 config KERNEL_DEBUG_KERNEL
108 config KERNEL_DEBUG_INFO
109 bool "Compile the kernel with debug information"
111 select KERNEL_DEBUG_KERNEL
113 This will compile your kernel and modules with debug information.
115 config KERNEL_DEBUG_LL_UART_NONE
120 config KERNEL_DEBUG_LL
124 select KERNEL_DEBUG_LL_UART_NONE
126 ARM low level debugging.
128 config KERNEL_DYNAMIC_DEBUG
129 bool "Compile the kernel with dynamic printk"
130 select KERNEL_DEBUG_FS
133 Compiles debug level messages into the kernel, which would not
134 otherwise be available at runtime. These messages can then be
135 enabled/disabled based on various levels of scope - per source file,
136 function, module, format string, and line number. This mechanism
137 implicitly compiles in all pr_debug() and dev_dbg() calls, which
138 enlarges the kernel text size by about 2%.
140 config KERNEL_EARLY_PRINTK
141 bool "Compile the kernel with early printk"
142 default y if TARGET_bcm53xx
145 select KERNEL_DEBUG_KERNEL
146 select KERNEL_DEBUG_LL if arm
148 Compile the kernel with early printk support. This is only useful for
149 debugging purposes to send messages over the serial console in early boot.
150 Enable this to debug early boot problems.
152 config KERNEL_KPROBES
153 bool "Compile the kernel with kprobes support"
156 select KERNEL_PERF_EVENTS
158 Compiles the kernel with KPROBES support, which allows you to trap
159 at almost any kernel address and execute a callback function.
160 register_kprobe() establishes a probepoint and specifies the
161 callback. Kprobes is useful for kernel debugging, non-intrusive
162 instrumentation and testing.
163 If in doubt, say "N".
165 config KERNEL_KPROBE_EVENT
167 default y if KERNEL_KPROBES
170 bool "Compile the kernel with asynchronous IO support"
173 config KERNEL_FHANDLE
174 bool "Compile the kernel with support for fhandle syscalls"
177 config KERNEL_FANOTIFY
178 bool "Compile the kernel with modern file notification support"
181 config KERNEL_BLK_DEV_BSG
182 bool "Compile the kernel with SCSI generic v4 support for any block device"
185 config KERNEL_MAGIC_SYSRQ
186 bool "Compile the kernel with SysRq support"
189 config KERNEL_DEBUG_PINCTRL
190 bool "Compile the kernel with pinctrl debugging"
191 select KERNEL_DEBUG_KERNEL
193 config KERNEL_DEBUG_GPIO
194 bool "Compile the kernel with gpio debugging"
195 select KERNEL_DEBUG_KERNEL
197 config KERNEL_COREDUMP
200 config KERNEL_ELF_CORE
201 bool "Enable process core dump support"
202 select KERNEL_COREDUMP
205 config KERNEL_PROVE_LOCKING
206 bool "Enable kernel lock checking"
207 select KERNEL_DEBUG_KERNEL
210 config KERNEL_PRINTK_TIME
211 bool "Enable printk timestamps"
214 config KERNEL_SLUB_DEBUG
217 config KERNEL_SLUB_DEBUG_ON
220 config KERNEL_SLABINFO
221 select KERNEL_SLUB_DEBUG
222 select KERNEL_SLUB_DEBUG_ON
223 bool "Enable /proc slab debug info"
225 config KERNEL_PROC_PAGE_MONITOR
226 bool "Enable /proc page monitoring"
232 bool "Enable kexec support"
235 bool "Enable rfkill support"
236 default RFKILL_SUPPORT
239 bool "Enable sparse check during kernel build"
242 config KERNEL_DEVTMPFS
243 bool "Compile the kernel with device tmpfs enabled"
246 devtmpfs is a simple, kernel-managed /dev filesystem. The kernel creates
247 devices nodes for all registered devices ti simplify boot, but leaves more
248 complex tasks to userspace (e.g. udev).
252 config KERNEL_DEVTMPFS_MOUNT
253 bool "Automatically mount devtmpfs after root filesystem is mounted"
259 bool "Enable kernel access key retention support"
262 config KERNEL_PERSISTENT_KEYRINGS
263 bool "Enable kernel persistent keyrings"
264 depends on KERNEL_KEYS
267 config KERNEL_BIG_KEYS
268 bool "Enable large payload keys on kernel keyrings"
269 depends on KERNEL_KEYS
272 config KERNEL_ENCRYPTED_KEYS
273 tristate "Enable keys with encrypted payloads on kernel keyrings"
274 depends on KERNEL_KEYS
278 # CGROUP support symbols
281 config KERNEL_CGROUPS
282 bool "Enable kernel cgroups"
287 config KERNEL_CGROUP_DEBUG
288 bool "Example debug cgroup subsystem"
291 This option enables a simple cgroup subsystem that
292 exports useful debugging information about the cgroups
295 config KERNEL_FREEZER
297 default y if KERNEL_CGROUP_FREEZER
299 config KERNEL_CGROUP_FREEZER
300 bool "Freezer cgroup subsystem"
303 Provides a way to freeze and unfreeze all tasks in a
306 config KERNEL_CGROUP_DEVICE
307 bool "Device controller for cgroups"
310 Provides a cgroup implementing whitelists for devices which
311 a process in the cgroup can mknod or open.
313 config KERNEL_CGROUP_PIDS
314 bool "PIDs cgroup subsystem"
317 Provides enforcement of process number limits in the scope of a
320 config KERNEL_CPUSETS
321 bool "Cpuset support"
324 This option will let you create and manage CPUSETs which
325 allow dynamically partitioning a system into sets of CPUs and
326 Memory Nodes and assigning tasks to run only within those sets.
327 This is primarily useful on large SMP or NUMA systems.
329 config KERNEL_PROC_PID_CPUSET
330 bool "Include legacy /proc/<pid>/cpuset file"
332 depends on KERNEL_CPUSETS
334 config KERNEL_CGROUP_CPUACCT
335 bool "Simple CPU accounting cgroup subsystem"
338 Provides a simple Resource Controller for monitoring the
339 total CPU consumed by the tasks in a cgroup.
341 config KERNEL_RESOURCE_COUNTERS
342 bool "Resource counters"
345 This option enables controller independent resource accounting
346 infrastructure that works with cgroups.
348 config KERNEL_MM_OWNER
350 default y if KERNEL_MEMCG
353 bool "Memory Resource Controller for Control Groups"
355 depends on KERNEL_RESOURCE_COUNTERS || !LINUX_3_18
357 Provides a memory resource controller that manages both anonymous
358 memory and page cache. (See Documentation/cgroups/memory.txt)
360 Note that setting this option increases fixed memory overhead
361 associated with each page of memory in the system. By this,
362 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
363 usage tracking struct at boot. Total amount of this is printed out
366 Only enable when you're ok with these tradeoffs and really
367 sure you need the memory resource controller. Even when you enable
368 this, you can set "cgroup_disable=memory" at your boot option to
369 disable memory resource controller and you can avoid overheads
370 (but lose benefits of memory resource controller).
372 This config option also selects MM_OWNER config option, which
373 could in turn add some fork/exit overhead.
375 config KERNEL_MEMCG_SWAP
376 bool "Memory Resource Controller Swap Extension"
378 depends on KERNEL_MEMCG
380 Add swap management feature to memory resource controller. When you
381 enable this, you can limit mem+swap usage per cgroup. In other words,
382 when you disable this, memory resource controller has no cares to
383 usage of swap...a process can exhaust all of the swap. This extension
384 is useful when you want to avoid exhaustion swap but this itself
385 adds more overheads and consumes memory for remembering information.
386 Especially if you use 32bit system or small memory system, please
387 be careful about enabling this. When memory resource controller
388 is disabled by boot option, this will be automatically disabled and
389 there will be no overhead from this. Even when you set this config=y,
390 if boot option "swapaccount=0" is set, swap will not be accounted.
391 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
392 size is 4096bytes, 512k per 1Gbytes of swap.
394 config KERNEL_MEMCG_SWAP_ENABLED
395 bool "Memory Resource Controller Swap Extension enabled by default"
397 depends on KERNEL_MEMCG_SWAP
399 Memory Resource Controller Swap Extension comes with its price in
400 a bigger memory consumption. General purpose distribution kernels
401 which want to enable the feature but keep it disabled by default
402 and let the user enable it by swapaccount boot command line
403 parameter should have this option unselected.
405 Those who want to have the feature enabled by default should
406 select this option (if, for some reason, they need to disable it,
407 then swapaccount=0 does the trick).
410 config KERNEL_MEMCG_KMEM
411 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
413 depends on KERNEL_MEMCG
415 The Kernel Memory extension for Memory Resource Controller can limit
416 the amount of memory used by kernel objects in the system. Those are
417 fundamentally different from the entities handled by the standard
418 Memory Controller, which are page-based, and can be swapped. Users of
419 the kmem extension can use it to guarantee that no group of processes
420 will ever exhaust kernel resources alone.
422 config KERNEL_CGROUP_PERF
423 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
424 select KERNEL_PERF_EVENTS
427 This option extends the per-cpu mode to restrict monitoring to
428 threads which belong to the cgroup specified and run on the
431 menuconfig KERNEL_CGROUP_SCHED
432 bool "Group CPU scheduler"
435 This feature lets CPU scheduler recognize task groups and control CPU
436 bandwidth allocation to such task groups. It uses cgroups to group
439 if KERNEL_CGROUP_SCHED
441 config KERNEL_FAIR_GROUP_SCHED
442 bool "Group scheduling for SCHED_OTHER"
445 config KERNEL_CFS_BANDWIDTH
446 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
448 depends on KERNEL_FAIR_GROUP_SCHED
450 This option allows users to define CPU bandwidth rates (limits) for
451 tasks running within the fair group scheduler. Groups with no limit
452 set are considered to be unconstrained and will run with no
454 See tip/Documentation/scheduler/sched-bwc.txt for more information.
456 config KERNEL_RT_GROUP_SCHED
457 bool "Group scheduling for SCHED_RR/FIFO"
460 This feature lets you explicitly allocate real CPU bandwidth
461 to task groups. If enabled, it will also make it impossible to
462 schedule realtime tasks for non-root users until you allocate
463 realtime bandwidth for them.
467 config KERNEL_BLK_CGROUP
468 bool "Block IO controller"
471 Generic block IO controller cgroup interface. This is the common
472 cgroup interface which should be used by various IO controlling
475 Currently, CFQ IO scheduler uses it to recognize task groups and
476 control disk bandwidth allocation (proportional time slice allocation)
477 to such task groups. It is also used by bio throttling logic in
478 block layer to implement upper limit in IO rates on a device.
480 This option only enables generic Block IO controller infrastructure.
481 One needs to also enable actual IO controlling logic/policy. For
482 enabling proportional weight division of disk bandwidth in CFQ, set
483 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
484 CONFIG_BLK_DEV_THROTTLING=y.
486 config KERNEL_DEBUG_BLK_CGROUP
487 bool "Enable Block IO controller debugging"
489 depends on KERNEL_BLK_CGROUP
491 Enable some debugging help. Currently it exports additional stat
492 files in a cgroup which can be useful for debugging.
494 config KERNEL_NET_CLS_CGROUP
495 bool "Control Group Classifier"
498 config KERNEL_NETPRIO_CGROUP
499 bool "Network priority cgroup"
505 # Namespace support symbols
508 config KERNEL_NAMESPACES
509 bool "Enable kernel namespaces"
518 In this namespace, tasks see different info provided
519 with the uname() system call.
525 In this namespace, tasks work with IPC ids which correspond to
526 different IPC objects in different namespaces.
528 config KERNEL_USER_NS
529 bool "User namespace (EXPERIMENTAL)"
532 This allows containers, i.e. vservers, to use user namespaces
533 to provide different user info for different servers.
536 bool "PID Namespaces"
539 Support process id namespaces. This allows having multiple
540 processes with the same pid as long as they are in different
541 pid namespaces. This is a building block of containers.
544 bool "Network namespace"
547 Allow user space to create what appear to be multiple instances
548 of the network stack.
553 # LXC related symbols
556 config KERNEL_LXC_MISC
557 bool "Enable miscellaneous LXC related options"
562 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
563 bool "Support multiple instances of devpts"
566 Enable support for multiple instances of devpts filesystem.
567 If you want to have isolated PTY namespaces (eg: in containers),
568 say Y here. Otherwise, say N. If enabled, each mount of devpts
569 filesystem with the '-o newinstance' option will create an
570 independent PTY namespace.
572 config KERNEL_POSIX_MQUEUE
573 bool "POSIX Message Queues"
576 POSIX variant of message queues is a part of IPC. In POSIX message
577 queues every message has a priority which decides about succession
578 of receiving it by a process. If you want to compile and run
579 programs written e.g. for Solaris with use of its POSIX message
580 queues (functions mq_*) say Y here.
582 POSIX message queues are visible as a filesystem called 'mqueue'
583 and can be mounted somewhere if you want to do filesystem
584 operations on message queues.
588 config KERNEL_SECCOMP_FILTER
592 config KERNEL_SECCOMP
593 bool "Enable seccomp support"
594 depends on !(TARGET_uml)
595 select KERNEL_SECCOMP_FILTER
598 Build kernel with support for seccomp.
609 config KERNEL_IPV6_MULTIPLE_TABLES
612 config KERNEL_IPV6_SUBTREES
615 config KERNEL_IPV6_MROUTE
618 config KERNEL_IPV6_PIMSM_V2
624 # NFS related symbols
627 bool "Compile the kernel with rootfs on NFS"
629 If you want to make your kernel boot off a NFS server as root
630 filesystem, select Y here.
634 config KERNEL_IP_PNP_DHCP
637 config KERNEL_IP_PNP_BOOTP
640 config KERNEL_IP_PNP_RARP
652 config KERNEL_ROOT_NFS
657 menu "Filesystem ACL and attr support options"
658 config USE_FS_ACL_ATTR
659 bool "Use filesystem ACL and attr support by default"
662 Make using ACLs (e.g. POSIX ACL, NFSv4 ACL) the default
663 for kernel and packages, except tmpfs, flash filesystems,
664 and old NFS. Also enable userspace extended attribute support
665 by default. (OpenWrt already has an expection it will be
666 present in the kernel).
668 config KERNEL_FS_POSIX_ACL
669 bool "Enable POSIX ACL support"
670 default y if USE_FS_ACL_ATTR
672 config KERNEL_BTRFS_FS_POSIX_ACL
673 bool "Enable POSIX ACL for BtrFS Filesystems"
674 select KERNEL_FS_POSIX_ACL
675 default y if USE_FS_ACL_ATTR
677 config KERNEL_EXT4_FS_POSIX_ACL
678 bool "Enable POSIX ACL for Ext4 Filesystems"
679 select KERNEL_FS_POSIX_ACL
680 default y if USE_FS_ACL_ATTR
682 config KERNEL_F2FS_FS_POSIX_ACL
683 bool "Enable POSIX ACL for F2FS Filesystems"
684 select KERNEL_FS_POSIX_ACL
687 config KERNEL_JFFS2_FS_POSIX_ACL
688 bool "Enable POSIX ACL for JFFS2 Filesystems"
689 select KERNEL_FS_POSIX_ACL
692 config KERNEL_TMPFS_POSIX_ACL
693 bool "Enable POSIX ACL for TMPFS Filesystems"
694 select KERNEL_FS_POSIX_ACL
697 config KERNEL_CIFS_ACL
698 bool "Enable CIFS ACLs"
699 select KERNEL_FS_POSIX_ACL
700 default y if USE_FS_ACL_ATTR
702 config KERNEL_HFS_FS_POSIX_ACL
703 bool "Enable POSIX ACL for HFS Filesystems"
704 select KERNEL_FS_POSIX_ACL
705 default y if USE_FS_ACL_ATTR
707 config KERNEL_HFSPLUG_FS_POSIX_ACL
708 bool "Enable POSIX ACL for HFS+ Filesystems"
709 select KERNEL_FS_POSIX_ACL
710 default y if USE_FS_ACL_ATTR
712 config KERNEL_NFS_ACL_SUPPORT
713 bool "Enable ACLs for NFS"
714 default y if USE_FS_ACL_ATTR
716 config KERNEL_NFS_V3_ACL_SUPPORT
717 bool "Enable ACLs for NFSv3"
720 config KERNEL_NFSD_V2_ACL_SUPPORT
721 bool "Enable ACLs for NFSDv2"
724 config KERNEL_NFSD_V3_ACL_SUPPORT
725 bool "Enable ACLs for NFSDv3"
728 config KERNEL_REISER_FS_POSIX_ACL
729 bool "Enable POSIX ACLs for ReiserFS"
730 select KERNEL_FS_POSIX_ACL
731 default y if USE_FS_ACL_ATTR
733 config KERNEL_XFS_POSIX_ACL
734 bool "Enable POSIX ACLs for XFS"
735 select KERNEL_FS_POSIX_ACL
736 default y if USE_FS_ACL_ATTR
738 config KERNEL_JFS_POSIX_ACL
739 bool "Enable POSIX ACLs for JFS"
740 select KERNEL_FS_POSIX_ACL
741 default y if USE_FS_ACL_ATTR
746 bool "/dev/mem virtual device support"
748 Say Y here if you want to support the /dev/mem device.
749 The /dev/mem device is used to access areas of physical
752 config KERNEL_DEVKMEM
753 bool "/dev/kmem virtual device support"
755 Say Y here if you want to support the /dev/kmem device. The
756 /dev/kmem device is rarely used, but can be used for certain
757 kind of kernel debugging operations.