tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#
2# For a description of the syntax of this configuration file,
3# see Documentation/kbuild/kconfig-language.txt.
4#
5# Note: ISA is disabled and will hopefully never be enabled.
6# If you managed to buy an ISA x86-64 box you'll have to fix all the
7# ISA drivers you need yourself.
8#
9
10mainmenu "Linux Kernel Configuration"
11
12config X86_64
13 bool
14 default y
15 help
16 Port to the x86-64 architecture. x86-64 is a 64-bit extension to the
17 classical 32-bit x86 architecture. For details see
18 <http://www.x86-64.org/>.
19
20config 64BIT
21 def_bool y
22
23config X86
24 bool
25 default y
26
27config GENERIC_TIME
28 bool
29 default y
30
31config GENERIC_TIME_VSYSCALL
32 bool
33 default y
34
35config ZONE_DMA32
36 bool
37 default y
38
39config LOCKDEP_SUPPORT
40 bool
41 default y
42
43config STACKTRACE_SUPPORT
44 bool
45 default y
46
47config SEMAPHORE_SLEEPERS
48 bool
49 default y
50
51config MMU
52 bool
53 default y
54
55config ZONE_DMA
56 bool
57 default y
58
59config ISA
60 bool
61
62config SBUS
63 bool
64
65config RWSEM_GENERIC_SPINLOCK
66 bool
67 default y
68
69config RWSEM_XCHGADD_ALGORITHM
70 bool
71
72config GENERIC_HWEIGHT
73 bool
74 default y
75
76config GENERIC_CALIBRATE_DELAY
77 bool
78 default y
79
80config X86_CMPXCHG
81 bool
82 default y
83
84config EARLY_PRINTK
85 bool
86 default y
87
88config GENERIC_ISA_DMA
89 bool
90 default y
91
92config GENERIC_IOMAP
93 bool
94 default y
95
96config ARCH_MAY_HAVE_PC_FDC
97 bool
98 default y
99
100config ARCH_POPULATES_NODE_MAP
101 def_bool y
102
103config DMI
104 bool
105 default y
106
107config AUDIT_ARCH
108 bool
109 default y
110
111config GENERIC_BUG
112 bool
113 default y
114 depends on BUG
115
116config ARCH_HAS_ILOG2_U32
117 bool
118 default n
119
120config ARCH_HAS_ILOG2_U64
121 bool
122 default n
123
124source "init/Kconfig"
125
126
127menu "Processor type and features"
128
129choice
130 prompt "Subarchitecture Type"
131 default X86_PC
132
133config X86_PC
134 bool "PC-compatible"
135 help
136 Choose this option if your computer is a standard PC or compatible.
137
138config X86_VSMP
139 bool "Support for ScaleMP vSMP"
140 depends on PCI
141 help
142 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
143 supposed to run on these EM64T-based machines. Only choose this option
144 if you have one of these machines.
145
146endchoice
147
148choice
149 prompt "Processor family"
150 default GENERIC_CPU
151
152config MK8
153 bool "AMD-Opteron/Athlon64"
154 help
155 Optimize for AMD Opteron/Athlon64/Hammer/K8 CPUs.
156
157config MPSC
158 bool "Intel P4 / older Netburst based Xeon"
159 help
160 Optimize for Intel Pentium 4 and older Nocona/Dempsey Xeon CPUs
161 with Intel Extended Memory 64 Technology(EM64T). For details see
162 <http://www.intel.com/technology/64bitextensions/>.
163 Note that the latest Xeons (Xeon 51xx and 53xx) are not based on the
164 Netburst core and shouldn't use this option. You can distinguish them
165 using the cpu family field
166 in /proc/cpuinfo. Family 15 is an older Xeon, Family 6 a newer one
167 (this rule only applies to systems that support EM64T)
168
169config MCORE2
170 bool "Intel Core2 / newer Xeon"
171 help
172 Optimize for Intel Core2 and newer Xeons (51xx)
173 You can distinguish the newer Xeons from the older ones using
174 the cpu family field in /proc/cpuinfo. 15 is an older Xeon
175 (use CONFIG_MPSC then), 6 is a newer one. This rule only
176 applies to CPUs that support EM64T.
177
178config GENERIC_CPU
179 bool "Generic-x86-64"
180 help
181 Generic x86-64 CPU.
182 Run equally well on all x86-64 CPUs.
183
184endchoice
185
186#
187# Define implied options from the CPU selection here
188#
189config X86_L1_CACHE_BYTES
190 int
191 default "128" if GENERIC_CPU || MPSC
192 default "64" if MK8 || MCORE2
193
194config X86_L1_CACHE_SHIFT
195 int
196 default "7" if GENERIC_CPU || MPSC
197 default "6" if MK8 || MCORE2
198
199config X86_INTERNODE_CACHE_BYTES
200 int
201 default "4096" if X86_VSMP
202 default X86_L1_CACHE_BYTES if !X86_VSMP
203
204config X86_TSC
205 bool
206 default y
207
208config X86_GOOD_APIC
209 bool
210 default y
211
212config MICROCODE
213 tristate "/dev/cpu/microcode - Intel CPU microcode support"
214 select FW_LOADER
215 ---help---
216 If you say Y here the 'File systems' section, you will be
217 able to update the microcode on Intel processors. You will
218 obviously need the actual microcode binary data itself which is
219 not shipped with the Linux kernel.
220
221 For latest news and information on obtaining all the required
222 ingredients for this driver, check:
223 <http://www.urbanmyth.org/microcode/>.
224
225 To compile this driver as a module, choose M here: the
226 module will be called microcode.
227 If you use modprobe or kmod you may also want to add the line
228 'alias char-major-10-184 microcode' to your /etc/modules.conf file.
229
230config MICROCODE_OLD_INTERFACE
231 bool
232 depends on MICROCODE
233 default y
234
235config X86_MSR
236 tristate "/dev/cpu/*/msr - Model-specific register support"
237 help
238 This device gives privileged processes access to the x86
239 Model-Specific Registers (MSRs). It is a character device with
240 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
241 MSR accesses are directed to a specific CPU on multi-processor
242 systems.
243
244config X86_CPUID
245 tristate "/dev/cpu/*/cpuid - CPU information support"
246 help
247 This device gives processes access to the x86 CPUID instruction to
248 be executed on a specific processor. It is a character device
249 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
250 /dev/cpu/31/cpuid.
251
252config X86_HT
253 bool
254 depends on SMP && !MK8
255 default y
256
257config MATH_EMULATION
258 bool
259
260config MCA
261 bool
262
263config EISA
264 bool
265
266config X86_IO_APIC
267 bool
268 default y
269
270config X86_LOCAL_APIC
271 bool
272 default y
273
274config MTRR
275 bool "MTRR (Memory Type Range Register) support"
276 ---help---
277 On Intel P6 family processors (Pentium Pro, Pentium II and later)
278 the Memory Type Range Registers (MTRRs) may be used to control
279 processor access to memory ranges. This is most useful if you have
280 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
281 allows bus write transfers to be combined into a larger transfer
282 before bursting over the PCI/AGP bus. This can increase performance
283 of image write operations 2.5 times or more. Saying Y here creates a
284 /proc/mtrr file which may be used to manipulate your processor's
285 MTRRs. Typically the X server should use this.
286
287 This code has a reasonably generic interface so that similar
288 control registers on other processors can be easily supported
289 as well.
290
291 Saying Y here also fixes a problem with buggy SMP BIOSes which only
292 set the MTRRs for the boot CPU and not for the secondary CPUs. This
293 can lead to all sorts of problems, so it's good to say Y here.
294
295 Just say Y here, all x86-64 machines support MTRRs.
296
297 See <file:Documentation/mtrr.txt> for more information.
298
299config SMP
300 bool "Symmetric multi-processing support"
301 ---help---
302 This enables support for systems with more than one CPU. If you have
303 a system with only one CPU, like most personal computers, say N. If
304 you have a system with more than one CPU, say Y.
305
306 If you say N here, the kernel will run on single and multiprocessor
307 machines, but will use only one CPU of a multiprocessor machine. If
308 you say Y here, the kernel will run on many, but not all,
309 singleprocessor machines. On a singleprocessor machine, the kernel
310 will run faster if you say N here.
311
312 If you don't know what to do here, say N.
313
314config SCHED_SMT
315 bool "SMT (Hyperthreading) scheduler support"
316 depends on SMP
317 default n
318 help
319 SMT scheduler support improves the CPU scheduler's decision making
320 when dealing with Intel Pentium 4 chips with HyperThreading at a
321 cost of slightly increased overhead in some places. If unsure say
322 N here.
323
324config SCHED_MC
325 bool "Multi-core scheduler support"
326 depends on SMP
327 default y
328 help
329 Multi-core scheduler support improves the CPU scheduler's decision
330 making when dealing with multi-core CPU chips at a cost of slightly
331 increased overhead in some places. If unsure say N here.
332
333source "kernel/Kconfig.preempt"
334
335config NUMA
336 bool "Non Uniform Memory Access (NUMA) Support"
337 depends on SMP
338 help
339 Enable NUMA (Non Uniform Memory Access) support. The kernel
340 will try to allocate memory used by a CPU on the local memory
341 controller of the CPU and add some more NUMA awareness to the kernel.
342 This code is recommended on all multiprocessor Opteron systems.
343 If the system is EM64T, you should say N unless your system is EM64T
344 NUMA.
345
346config K8_NUMA
347 bool "Old style AMD Opteron NUMA detection"
348 depends on NUMA && PCI
349 default y
350 help
351 Enable K8 NUMA node topology detection. You should say Y here if
352 you have a multi processor AMD K8 system. This uses an old
353 method to read the NUMA configuration directly from the builtin
354 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
355 instead, which also takes priority if both are compiled in.
356
357config NODES_SHIFT
358 int
359 default "6"
360 depends on NEED_MULTIPLE_NODES
361
362# Dummy CONFIG option to select ACPI_NUMA from drivers/acpi/Kconfig.
363
364config X86_64_ACPI_NUMA
365 bool "ACPI NUMA detection"
366 depends on NUMA
367 select ACPI
368 select PCI
369 select ACPI_NUMA
370 default y
371 help
372 Enable ACPI SRAT based node topology detection.
373
374config NUMA_EMU
375 bool "NUMA emulation"
376 depends on NUMA
377 help
378 Enable NUMA emulation. A flat machine will be split
379 into virtual nodes when booted with "numa=fake=N", where N is the
380 number of nodes. This is only useful for debugging.
381
382config ARCH_DISCONTIGMEM_ENABLE
383 bool
384 depends on NUMA
385 default y
386
387config ARCH_DISCONTIGMEM_DEFAULT
388 def_bool y
389 depends on NUMA
390
391config ARCH_SPARSEMEM_ENABLE
392 def_bool y
393 depends on (NUMA || EXPERIMENTAL)
394
395config ARCH_MEMORY_PROBE
396 def_bool y
397 depends on MEMORY_HOTPLUG
398
399config ARCH_FLATMEM_ENABLE
400 def_bool y
401 depends on !NUMA
402
403source "mm/Kconfig"
404
405config MEMORY_HOTPLUG_RESERVE
406 def_bool y
407 depends on (MEMORY_HOTPLUG && DISCONTIGMEM)
408
409config HAVE_ARCH_EARLY_PFN_TO_NID
410 def_bool y
411 depends on NUMA
412
413config OUT_OF_LINE_PFN_TO_PAGE
414 def_bool y
415 depends on DISCONTIGMEM
416
417config NR_CPUS
418 int "Maximum number of CPUs (2-255)"
419 range 2 255
420 depends on SMP
421 default "8"
422 help
423 This allows you to specify the maximum number of CPUs which this
424 kernel will support. Current maximum is 255 CPUs due to
425 APIC addressing limits. Less depending on the hardware.
426
427 This is purely to save memory - each supported CPU requires
428 memory in the static kernel configuration.
429
430config HOTPLUG_CPU
431 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
432 depends on SMP && HOTPLUG && EXPERIMENTAL
433 help
434 Say Y here to experiment with turning CPUs off and on. CPUs
435 can be controlled through /sys/devices/system/cpu/cpu#.
436 This is also required for suspend/hibernation on SMP systems.
437
438 Say N if you want to disable CPU hotplug and don't need to
439 suspend.
440
441config ARCH_ENABLE_MEMORY_HOTPLUG
442 def_bool y
443
444config HPET_TIMER
445 bool
446 default y
447 help
448 Use the IA-PC HPET (High Precision Event Timer) to manage
449 time in preference to the PIT and RTC, if a HPET is
450 present. The HPET provides a stable time base on SMP
451 systems, unlike the TSC, but it is more expensive to access,
452 as it is off-chip. You can find the HPET spec at
453 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
454
455config HPET_EMULATE_RTC
456 bool "Provide RTC interrupt"
457 depends on HPET_TIMER && RTC=y
458
459# Mark as embedded because too many people got it wrong.
460# The code disables itself when not needed.
461config IOMMU
462 bool "IOMMU support" if EMBEDDED
463 default y
464 select SWIOTLB
465 select AGP
466 depends on PCI
467 help
468 Support for full DMA access of devices with 32bit memory access only
469 on systems with more than 3GB. This is usually needed for USB,
470 sound, many IDE/SATA chipsets and some other devices.
471 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
472 based hardware IOMMU and a software bounce buffer based IOMMU used
473 on Intel systems and as fallback.
474 The code is only active when needed (enough memory and limited
475 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
476 too.
477
478config CALGARY_IOMMU
479 bool "IBM Calgary IOMMU support"
480 select SWIOTLB
481 depends on PCI && EXPERIMENTAL
482 help
483 Support for hardware IOMMUs in IBM's xSeries x366 and x460
484 systems. Needed to run systems with more than 3GB of memory
485 properly with 32-bit PCI devices that do not support DAC
486 (Double Address Cycle). Calgary also supports bus level
487 isolation, where all DMAs pass through the IOMMU. This
488 prevents them from going anywhere except their intended
489 destination. This catches hard-to-find kernel bugs and
490 mis-behaving drivers and devices that do not use the DMA-API
491 properly to set up their DMA buffers. The IOMMU can be
492 turned off at boot time with the iommu=off parameter.
493 Normally the kernel will make the right choice by itself.
494 If unsure, say Y.
495
496config CALGARY_IOMMU_ENABLED_BY_DEFAULT
497 bool "Should Calgary be enabled by default?"
498 default y
499 depends on CALGARY_IOMMU
500 help
501 Should Calgary be enabled by default? if you choose 'y', Calgary
502 will be used (if it exists). If you choose 'n', Calgary will not be
503 used even if it exists. If you choose 'n' and would like to use
504 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
505 If unsure, say Y.
506
507# need this always selected by IOMMU for the VIA workaround
508config SWIOTLB
509 bool
510 help
511 Support for software bounce buffers used on x86-64 systems
512 which don't have a hardware IOMMU (e.g. the current generation
513 of Intel's x86-64 CPUs). Using this PCI devices which can only
514 access 32-bits of memory can be used on systems with more than
515 3 GB of memory. If unsure, say Y.
516
517config X86_MCE
518 bool "Machine check support" if EMBEDDED
519 default y
520 help
521 Include a machine check error handler to report hardware errors.
522 This version will require the mcelog utility to decode some
523 machine check error logs. See
524 ftp://ftp.x86-64.org/pub/linux/tools/mcelog
525
526config X86_MCE_INTEL
527 bool "Intel MCE features"
528 depends on X86_MCE && X86_LOCAL_APIC
529 default y
530 help
531 Additional support for intel specific MCE features such as
532 the thermal monitor.
533
534config X86_MCE_AMD
535 bool "AMD MCE features"
536 depends on X86_MCE && X86_LOCAL_APIC
537 default y
538 help
539 Additional support for AMD specific MCE features such as
540 the DRAM Error Threshold.
541
542config KEXEC
543 bool "kexec system call"
544 help
545 kexec is a system call that implements the ability to shutdown your
546 current kernel, and to start another kernel. It is like a reboot
547 but it is independent of the system firmware. And like a reboot
548 you can start any kernel with it, not just Linux.
549
550 The name comes from the similarity to the exec system call.
551
552 It is an ongoing process to be certain the hardware in a machine
553 is properly shutdown, so do not be surprised if this code does not
554 initially work for you. It may help to enable device hotplugging
555 support. As of this writing the exact hardware interface is
556 strongly in flux, so no good recommendation can be made.
557
558config CRASH_DUMP
559 bool "kernel crash dumps (EXPERIMENTAL)"
560 depends on EXPERIMENTAL
561 help
562 Generate crash dump after being started by kexec.
563 This should be normally only set in special crash dump kernels
564 which are loaded in the main kernel with kexec-tools into
565 a specially reserved region and then later executed after
566 a crash by kdump/kexec. The crash dump kernel must be compiled
567 to a memory address not used by the main kernel or BIOS using
568 PHYSICAL_START.
569 For more details see Documentation/kdump/kdump.txt
570
571config RELOCATABLE
572 bool "Build a relocatable kernel(EXPERIMENTAL)"
573 depends on EXPERIMENTAL
574 help
575 Builds a relocatable kernel. This enables loading and running
576 a kernel binary from a different physical address than it has
577 been compiled for.
578
579 One use is for the kexec on panic case where the recovery kernel
580 must live at a different physical address than the primary
581 kernel.
582
583 Note: If CONFIG_RELOCATABLE=y, then kernel run from the address
584 it has been loaded at and compile time physical address
585 (CONFIG_PHYSICAL_START) is ignored.
586
587config PHYSICAL_START
588 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
589 default "0x200000"
590 help
591 This gives the physical address where the kernel is loaded. It
592 should be aligned to 2MB boundary.
593
594 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
595 bzImage will decompress itself to above physical address and
596 run from there. Otherwise, bzImage will run from the address where
597 it has been loaded by the boot loader and will ignore above physical
598 address.
599
600 In normal kdump cases one does not have to set/change this option
601 as now bzImage can be compiled as a completely relocatable image
602 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
603 address. This option is mainly useful for the folks who don't want
604 to use a bzImage for capturing the crash dump and want to use a
605 vmlinux instead.
606
607 So if you are using bzImage for capturing the crash dump, leave
608 the value here unchanged to 0x200000 and set CONFIG_RELOCATABLE=y.
609 Otherwise if you plan to use vmlinux for capturing the crash dump
610 change this value to start of the reserved region (Typically 16MB
611 0x1000000). In other words, it can be set based on the "X" value as
612 specified in the "crashkernel=YM@XM" command line boot parameter
613 passed to the panic-ed kernel. Typically this parameter is set as
614 crashkernel=64M@16M. Please take a look at
615 Documentation/kdump/kdump.txt for more details about crash dumps.
616
617 Usage of bzImage for capturing the crash dump is advantageous as
618 one does not have to build two kernels. Same kernel can be used
619 as production kernel and capture kernel.
620
621 Don't change this unless you know what you are doing.
622
623config SECCOMP
624 bool "Enable seccomp to safely compute untrusted bytecode"
625 depends on PROC_FS
626 default y
627 help
628 This kernel feature is useful for number crunching applications
629 that may need to compute untrusted bytecode during their
630 execution. By using pipes or other transports made available to
631 the process as file descriptors supporting the read/write
632 syscalls, it's possible to isolate those applications in
633 their own address space using seccomp. Once seccomp is
634 enabled via /proc/<pid>/seccomp, it cannot be disabled
635 and the task is only allowed to execute a few safe syscalls
636 defined by each seccomp mode.
637
638 If unsure, say Y. Only embedded should say N here.
639
640config CC_STACKPROTECTOR
641 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
642 depends on EXPERIMENTAL
643 help
644 This option turns on the -fstack-protector GCC feature. This
645 feature puts, at the beginning of critical functions, a canary
646 value on the stack just before the return address, and validates
647 the value just before actually returning. Stack based buffer
648 overflows (that need to overwrite this return address) now also
649 overwrite the canary, which gets detected and the attack is then
650 neutralized via a kernel panic.
651
652 This feature requires gcc version 4.2 or above, or a distribution
653 gcc with the feature backported. Older versions are automatically
654 detected and for those versions, this configuration option is ignored.
655
656config CC_STACKPROTECTOR_ALL
657 bool "Use stack-protector for all functions"
658 depends on CC_STACKPROTECTOR
659 help
660 Normally, GCC only inserts the canary value protection for
661 functions that use large-ish on-stack buffers. By enabling
662 this option, GCC will be asked to do this for ALL functions.
663
664source kernel/Kconfig.hz
665
666config K8_NB
667 def_bool y
668 depends on AGP_AMD64 || IOMMU || (PCI && NUMA)
669
670endmenu
671
672#
673# Use the generic interrupt handling code in kernel/irq/:
674#
675config GENERIC_HARDIRQS
676 bool
677 default y
678
679config GENERIC_IRQ_PROBE
680 bool
681 default y
682
683# we have no ISA slots, but we do have ISA-style DMA.
684config ISA_DMA_API
685 bool
686 default y
687
688config GENERIC_PENDING_IRQ
689 bool
690 depends on GENERIC_HARDIRQS && SMP
691 default y
692
693menu "Power management options"
694
695source kernel/power/Kconfig
696
697source "drivers/acpi/Kconfig"
698
699source "arch/x86_64/kernel/cpufreq/Kconfig"
700
701endmenu
702
703menu "Bus options (PCI etc.)"
704
705config PCI
706 bool "PCI support"
707 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
708
709# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
710config PCI_DIRECT
711 bool
712 depends on PCI
713 default y
714
715config PCI_MMCONFIG
716 bool "Support mmconfig PCI config space access"
717 depends on PCI && ACPI
718
719source "drivers/pci/pcie/Kconfig"
720
721source "drivers/pci/Kconfig"
722
723source "drivers/pcmcia/Kconfig"
724
725source "drivers/pci/hotplug/Kconfig"
726
727endmenu
728
729
730menu "Executable file formats / Emulations"
731
732source "fs/Kconfig.binfmt"
733
734config IA32_EMULATION
735 bool "IA32 Emulation"
736 help
737 Include code to run 32-bit programs under a 64-bit kernel. You should likely
738 turn this on, unless you're 100% sure that you don't have any 32-bit programs
739 left.
740
741config IA32_AOUT
742 tristate "IA32 a.out support"
743 depends on IA32_EMULATION
744 help
745 Support old a.out binaries in the 32bit emulation.
746
747config COMPAT
748 bool
749 depends on IA32_EMULATION
750 default y
751
752config SYSVIPC_COMPAT
753 bool
754 depends on COMPAT && SYSVIPC
755 default y
756
757endmenu
758
759source "net/Kconfig"
760
761source drivers/Kconfig
762
763source "drivers/firmware/Kconfig"
764
765source fs/Kconfig
766
767menu "Instrumentation Support"
768 depends on EXPERIMENTAL
769
770source "arch/x86_64/oprofile/Kconfig"
771
772config KPROBES
773 bool "Kprobes (EXPERIMENTAL)"
774 depends on KALLSYMS && EXPERIMENTAL && MODULES
775 help
776 Kprobes allows you to trap at almost any kernel address and
777 execute a callback function. register_kprobe() establishes
778 a probepoint and specifies the callback. Kprobes is useful
779 for kernel debugging, non-intrusive instrumentation and testing.
780 If in doubt, say "N".
781endmenu
782
783source "arch/x86_64/Kconfig.debug"
784
785source "security/Kconfig"
786
787source "crypto/Kconfig"
788
789source "lib/Kconfig"