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
51 bool "Compile the kernel with performance events and counters"
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"
234 config KERNEL_PROC_VMCORE
237 config KERNEL_CRASH_DUMP
238 depends on i386 || x86_64 || arm || armeb
240 select KERNEL_PROC_VMCORE
241 bool "Enable support for kexec crashdump"
245 bool "Enable rfkill support"
246 default RFKILL_SUPPORT
249 bool "Enable sparse check during kernel build"
252 config KERNEL_DEVTMPFS
253 bool "Compile the kernel with device tmpfs enabled"
256 devtmpfs is a simple, kernel-managed /dev filesystem. The kernel creates
257 devices nodes for all registered devices to simplify boot, but leaves more
258 complex tasks to userspace (e.g. udev).
262 config KERNEL_DEVTMPFS_MOUNT
263 bool "Automatically mount devtmpfs after root filesystem is mounted"
269 bool "Enable kernel access key retention support"
272 config KERNEL_PERSISTENT_KEYRINGS
273 bool "Enable kernel persistent keyrings"
274 depends on KERNEL_KEYS
277 config KERNEL_BIG_KEYS
278 bool "Enable large payload keys on kernel keyrings"
279 depends on KERNEL_KEYS
282 config KERNEL_ENCRYPTED_KEYS
283 tristate "Enable keys with encrypted payloads on kernel keyrings"
284 depends on KERNEL_KEYS
288 # CGROUP support symbols
291 config KERNEL_CGROUPS
292 bool "Enable kernel cgroups"
297 config KERNEL_CGROUP_DEBUG
298 bool "Example debug cgroup subsystem"
301 This option enables a simple cgroup subsystem that
302 exports useful debugging information about the cgroups
305 config KERNEL_FREEZER
307 default y if KERNEL_CGROUP_FREEZER
309 config KERNEL_CGROUP_FREEZER
310 bool "Freezer cgroup subsystem"
313 Provides a way to freeze and unfreeze all tasks in a
316 config KERNEL_CGROUP_DEVICE
317 bool "Device controller for cgroups"
320 Provides a cgroup implementing whitelists for devices which
321 a process in the cgroup can mknod or open.
323 config KERNEL_CGROUP_PIDS
324 bool "PIDs cgroup subsystem"
327 Provides enforcement of process number limits in the scope of a
330 config KERNEL_CPUSETS
331 bool "Cpuset support"
334 This option will let you create and manage CPUSETs which
335 allow dynamically partitioning a system into sets of CPUs and
336 Memory Nodes and assigning tasks to run only within those sets.
337 This is primarily useful on large SMP or NUMA systems.
339 config KERNEL_PROC_PID_CPUSET
340 bool "Include legacy /proc/<pid>/cpuset file"
342 depends on KERNEL_CPUSETS
344 config KERNEL_CGROUP_CPUACCT
345 bool "Simple CPU accounting cgroup subsystem"
348 Provides a simple Resource Controller for monitoring the
349 total CPU consumed by the tasks in a cgroup.
351 config KERNEL_RESOURCE_COUNTERS
352 bool "Resource counters"
355 This option enables controller independent resource accounting
356 infrastructure that works with cgroups.
358 config KERNEL_MM_OWNER
360 default y if KERNEL_MEMCG
363 bool "Memory Resource Controller for Control Groups"
365 depends on KERNEL_RESOURCE_COUNTERS || !LINUX_3_18
367 Provides a memory resource controller that manages both anonymous
368 memory and page cache. (See Documentation/cgroups/memory.txt)
370 Note that setting this option increases fixed memory overhead
371 associated with each page of memory in the system. By this,
372 20(40)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
373 usage tracking struct at boot. Total amount of this is printed out
376 Only enable when you're ok with these tradeoffs and really
377 sure you need the memory resource controller. Even when you enable
378 this, you can set "cgroup_disable=memory" at your boot option to
379 disable memory resource controller and you can avoid overheads
380 (but lose benefits of memory resource controller).
382 This config option also selects MM_OWNER config option, which
383 could in turn add some fork/exit overhead.
385 config KERNEL_MEMCG_SWAP
386 bool "Memory Resource Controller Swap Extension"
388 depends on KERNEL_MEMCG
390 Add swap management feature to memory resource controller. When you
391 enable this, you can limit mem+swap usage per cgroup. In other words,
392 when you disable this, memory resource controller has no cares to
393 usage of swap...a process can exhaust all of the swap. This extension
394 is useful when you want to avoid exhaustion swap but this itself
395 adds more overheads and consumes memory for remembering information.
396 Especially if you use 32bit system or small memory system, please
397 be careful about enabling this. When memory resource controller
398 is disabled by boot option, this will be automatically disabled and
399 there will be no overhead from this. Even when you set this config=y,
400 if boot option "swapaccount=0" is set, swap will not be accounted.
401 Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
402 size is 4096bytes, 512k per 1Gbytes of swap.
404 config KERNEL_MEMCG_SWAP_ENABLED
405 bool "Memory Resource Controller Swap Extension enabled by default"
407 depends on KERNEL_MEMCG_SWAP
409 Memory Resource Controller Swap Extension comes with its price in
410 a bigger memory consumption. General purpose distribution kernels
411 which want to enable the feature but keep it disabled by default
412 and let the user enable it by swapaccount boot command line
413 parameter should have this option unselected.
415 Those who want to have the feature enabled by default should
416 select this option (if, for some reason, they need to disable it,
417 then swapaccount=0 does the trick).
420 config KERNEL_MEMCG_KMEM
421 bool "Memory Resource Controller Kernel Memory accounting (EXPERIMENTAL)"
423 depends on KERNEL_MEMCG
425 The Kernel Memory extension for Memory Resource Controller can limit
426 the amount of memory used by kernel objects in the system. Those are
427 fundamentally different from the entities handled by the standard
428 Memory Controller, which are page-based, and can be swapped. Users of
429 the kmem extension can use it to guarantee that no group of processes
430 will ever exhaust kernel resources alone.
432 config KERNEL_CGROUP_PERF
433 bool "Enable perf_event per-cpu per-container group (cgroup) monitoring"
434 select KERNEL_PERF_EVENTS
437 This option extends the per-cpu mode to restrict monitoring to
438 threads which belong to the cgroup specified and run on the
441 menuconfig KERNEL_CGROUP_SCHED
442 bool "Group CPU scheduler"
445 This feature lets CPU scheduler recognize task groups and control CPU
446 bandwidth allocation to such task groups. It uses cgroups to group
449 if KERNEL_CGROUP_SCHED
451 config KERNEL_FAIR_GROUP_SCHED
452 bool "Group scheduling for SCHED_OTHER"
455 config KERNEL_CFS_BANDWIDTH
456 bool "CPU bandwidth provisioning for FAIR_GROUP_SCHED"
458 depends on KERNEL_FAIR_GROUP_SCHED
460 This option allows users to define CPU bandwidth rates (limits) for
461 tasks running within the fair group scheduler. Groups with no limit
462 set are considered to be unconstrained and will run with no
464 See tip/Documentation/scheduler/sched-bwc.txt for more information.
466 config KERNEL_RT_GROUP_SCHED
467 bool "Group scheduling for SCHED_RR/FIFO"
470 This feature lets you explicitly allocate real CPU bandwidth
471 to task groups. If enabled, it will also make it impossible to
472 schedule realtime tasks for non-root users until you allocate
473 realtime bandwidth for them.
477 config KERNEL_BLK_CGROUP
478 bool "Block IO controller"
481 Generic block IO controller cgroup interface. This is the common
482 cgroup interface which should be used by various IO controlling
485 Currently, CFQ IO scheduler uses it to recognize task groups and
486 control disk bandwidth allocation (proportional time slice allocation)
487 to such task groups. It is also used by bio throttling logic in
488 block layer to implement upper limit in IO rates on a device.
490 This option only enables generic Block IO controller infrastructure.
491 One needs to also enable actual IO controlling logic/policy. For
492 enabling proportional weight division of disk bandwidth in CFQ, set
493 CONFIG_CFQ_GROUP_IOSCHED=y; for enabling throttling policy, set
494 CONFIG_BLK_DEV_THROTTLING=y.
496 config KERNEL_DEBUG_BLK_CGROUP
497 bool "Enable Block IO controller debugging"
499 depends on KERNEL_BLK_CGROUP
501 Enable some debugging help. Currently it exports additional stat
502 files in a cgroup which can be useful for debugging.
504 config KERNEL_NET_CLS_CGROUP
505 bool "Control Group Classifier"
508 config KERNEL_NETPRIO_CGROUP
509 bool "Network priority cgroup"
515 # Namespace support symbols
518 config KERNEL_NAMESPACES
519 bool "Enable kernel namespaces"
528 In this namespace, tasks see different info provided
529 with the uname() system call.
535 In this namespace, tasks work with IPC ids which correspond to
536 different IPC objects in different namespaces.
538 config KERNEL_USER_NS
539 bool "User namespace (EXPERIMENTAL)"
542 This allows containers, i.e. vservers, to use user namespaces
543 to provide different user info for different servers.
546 bool "PID Namespaces"
549 Support process id namespaces. This allows having multiple
550 processes with the same pid as long as they are in different
551 pid namespaces. This is a building block of containers.
554 bool "Network namespace"
557 Allow user space to create what appear to be multiple instances
558 of the network stack.
563 # LXC related symbols
566 config KERNEL_LXC_MISC
567 bool "Enable miscellaneous LXC related options"
572 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
573 bool "Support multiple instances of devpts"
576 Enable support for multiple instances of devpts filesystem.
577 If you want to have isolated PTY namespaces (eg: in containers),
578 say Y here. Otherwise, say N. If enabled, each mount of devpts
579 filesystem with the '-o newinstance' option will create an
580 independent PTY namespace.
582 config KERNEL_POSIX_MQUEUE
583 bool "POSIX Message Queues"
586 POSIX variant of message queues is a part of IPC. In POSIX message
587 queues every message has a priority which decides about succession
588 of receiving it by a process. If you want to compile and run
589 programs written e.g. for Solaris with use of its POSIX message
590 queues (functions mq_*) say Y here.
592 POSIX message queues are visible as a filesystem called 'mqueue'
593 and can be mounted somewhere if you want to do filesystem
594 operations on message queues.
598 config KERNEL_SECCOMP_FILTER
602 config KERNEL_SECCOMP
603 bool "Enable seccomp support"
604 depends on !(TARGET_uml)
605 select KERNEL_SECCOMP_FILTER
608 Build kernel with support for seccomp.
614 config KERNEL_IP_MROUTE
615 bool "Enable IPv4 multicast routing"
618 Multicast routing requires a multicast routing daemon in
619 addition to kernel support.
630 config KERNEL_IPV6_MULTIPLE_TABLES
633 config KERNEL_IPV6_SUBTREES
636 config KERNEL_IPV6_MROUTE
637 bool "Enable IPv6 multicast routing"
640 Multicast routing requires a multicast routing daemon in
641 addition to kernel support.
643 config KERNEL_IPV6_PIMSM_V2
649 # NFS related symbols
652 bool "Compile the kernel with rootfs on NFS"
654 If you want to make your kernel boot off a NFS server as root
655 filesystem, select Y here.
659 config KERNEL_IP_PNP_DHCP
662 config KERNEL_IP_PNP_BOOTP
665 config KERNEL_IP_PNP_RARP
677 config KERNEL_ROOT_NFS
682 menu "Filesystem ACL and attr support options"
683 config USE_FS_ACL_ATTR
684 bool "Use filesystem ACL and attr support by default"
687 Make using ACLs (e.g. POSIX ACL, NFSv4 ACL) the default
688 for kernel and packages, except tmpfs, flash filesystems,
689 and old NFS. Also enable userspace extended attribute support
690 by default. (OpenWrt already has an expection it will be
691 present in the kernel).
693 config KERNEL_FS_POSIX_ACL
694 bool "Enable POSIX ACL support"
695 default y if USE_FS_ACL_ATTR
697 config KERNEL_BTRFS_FS_POSIX_ACL
698 bool "Enable POSIX ACL for BtrFS Filesystems"
699 select KERNEL_FS_POSIX_ACL
700 default y if USE_FS_ACL_ATTR
702 config KERNEL_EXT4_FS_POSIX_ACL
703 bool "Enable POSIX ACL for Ext4 Filesystems"
704 select KERNEL_FS_POSIX_ACL
705 default y if USE_FS_ACL_ATTR
707 config KERNEL_F2FS_FS_POSIX_ACL
708 bool "Enable POSIX ACL for F2FS Filesystems"
709 select KERNEL_FS_POSIX_ACL
712 config KERNEL_JFFS2_FS_POSIX_ACL
713 bool "Enable POSIX ACL for JFFS2 Filesystems"
714 select KERNEL_FS_POSIX_ACL
717 config KERNEL_TMPFS_POSIX_ACL
718 bool "Enable POSIX ACL for TMPFS Filesystems"
719 select KERNEL_FS_POSIX_ACL
722 config KERNEL_CIFS_ACL
723 bool "Enable CIFS ACLs"
724 select KERNEL_FS_POSIX_ACL
725 default y if USE_FS_ACL_ATTR
727 config KERNEL_HFS_FS_POSIX_ACL
728 bool "Enable POSIX ACL for HFS Filesystems"
729 select KERNEL_FS_POSIX_ACL
730 default y if USE_FS_ACL_ATTR
732 config KERNEL_HFSPLUG_FS_POSIX_ACL
733 bool "Enable POSIX ACL for HFS+ Filesystems"
734 select KERNEL_FS_POSIX_ACL
735 default y if USE_FS_ACL_ATTR
737 config KERNEL_NFS_ACL_SUPPORT
738 bool "Enable ACLs for NFS"
739 default y if USE_FS_ACL_ATTR
741 config KERNEL_NFS_V3_ACL_SUPPORT
742 bool "Enable ACLs for NFSv3"
745 config KERNEL_NFSD_V2_ACL_SUPPORT
746 bool "Enable ACLs for NFSDv2"
749 config KERNEL_NFSD_V3_ACL_SUPPORT
750 bool "Enable ACLs for NFSDv3"
753 config KERNEL_REISER_FS_POSIX_ACL
754 bool "Enable POSIX ACLs for ReiserFS"
755 select KERNEL_FS_POSIX_ACL
756 default y if USE_FS_ACL_ATTR
758 config KERNEL_XFS_POSIX_ACL
759 bool "Enable POSIX ACLs for XFS"
760 select KERNEL_FS_POSIX_ACL
761 default y if USE_FS_ACL_ATTR
763 config KERNEL_JFS_POSIX_ACL
764 bool "Enable POSIX ACLs for JFS"
765 select KERNEL_FS_POSIX_ACL
766 default y if USE_FS_ACL_ATTR
771 bool "/dev/mem virtual device support"
773 Say Y here if you want to support the /dev/mem device.
774 The /dev/mem device is used to access areas of physical
777 config KERNEL_DEVKMEM
778 bool "/dev/kmem virtual device support"
780 Say Y here if you want to support the /dev/kmem device. The
781 /dev/kmem device is rarely used, but can be used for certain
782 kind of kernel debugging operations.