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authorSam Ravnborg <sam@ravnborg.org>2007-11-09 15:56:54 -0500
committerSam Ravnborg <sam@ravnborg.org>2007-11-12 15:02:19 -0500
commit506f1d07b310815d11527d3360b09d79d0bd59f1 (patch)
tree3a2b1a7699916c0c9518db84d3cc060301ef5b81 /arch/x86
parent8d5fffb928cd86a70823f66f8335fa41709ec109 (diff)
x86: move the rest of the menu's to Kconfig
With this patch we have all the Kconfig file shared between i386 and x86_64. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com>
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/Kconfig1052
-rw-r--r--arch/x86/Kconfig.i3861053
-rw-r--r--arch/x86/Kconfig.x86_64490
3 files changed, 1052 insertions, 1543 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d47b5a2e4a32..34517bf14ba4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -151,7 +151,1059 @@ config X86_TRAMPOLINE
151 151
152config KTIME_SCALAR 152config KTIME_SCALAR
153 def_bool X86_32 153 def_bool X86_32
154source "init/Kconfig"
154 155
156menu "Processor type and features"
157
158source "kernel/time/Kconfig"
159
160config SMP
161 bool "Symmetric multi-processing support"
162 ---help---
163 This enables support for systems with more than one CPU. If you have
164 a system with only one CPU, like most personal computers, say N. If
165 you have a system with more than one CPU, say Y.
166
167 If you say N here, the kernel will run on single and multiprocessor
168 machines, but will use only one CPU of a multiprocessor machine. If
169 you say Y here, the kernel will run on many, but not all,
170 singleprocessor machines. On a singleprocessor machine, the kernel
171 will run faster if you say N here.
172
173 Note that if you say Y here and choose architecture "586" or
174 "Pentium" under "Processor family", the kernel will not work on 486
175 architectures. Similarly, multiprocessor kernels for the "PPro"
176 architecture may not work on all Pentium based boards.
177
178 People using multiprocessor machines who say Y here should also say
179 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
180 Management" code will be disabled if you say Y here.
181
182 See also the <file:Documentation/smp.txt>,
183 <file:Documentation/i386/IO-APIC.txt>,
184 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
185 <http://www.tldp.org/docs.html#howto>.
186
187 If you don't know what to do here, say N.
188
189choice
190 prompt "Subarchitecture Type"
191 default X86_PC
192
193config X86_PC
194 bool "PC-compatible"
195 help
196 Choose this option if your computer is a standard PC or compatible.
197
198config X86_ELAN
199 bool "AMD Elan"
200 depends on X86_32
201 help
202 Select this for an AMD Elan processor.
203
204 Do not use this option for K6/Athlon/Opteron processors!
205
206 If unsure, choose "PC-compatible" instead.
207
208config X86_VOYAGER
209 bool "Voyager (NCR)"
210 depends on X86_32
211 select SMP if !BROKEN
212 help
213 Voyager is an MCA-based 32-way capable SMP architecture proprietary
214 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
215
216 *** WARNING ***
217
218 If you do not specifically know you have a Voyager based machine,
219 say N here, otherwise the kernel you build will not be bootable.
220
221config X86_NUMAQ
222 bool "NUMAQ (IBM/Sequent)"
223 select SMP
224 select NUMA
225 depends on X86_32
226 help
227 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
228 multiquad box. This changes the way that processors are bootstrapped,
229 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
230 You will need a new lynxer.elf file to flash your firmware with - send
231 email to <Martin.Bligh@us.ibm.com>.
232
233config X86_SUMMIT
234 bool "Summit/EXA (IBM x440)"
235 depends on X86_32 && SMP
236 help
237 This option is needed for IBM systems that use the Summit/EXA chipset.
238 In particular, it is needed for the x440.
239
240 If you don't have one of these computers, you should say N here.
241 If you want to build a NUMA kernel, you must select ACPI.
242
243config X86_BIGSMP
244 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
245 depends on X86_32 && SMP
246 help
247 This option is needed for the systems that have more than 8 CPUs
248 and if the system is not of any sub-arch type above.
249
250 If you don't have such a system, you should say N here.
251
252config X86_VISWS
253 bool "SGI 320/540 (Visual Workstation)"
254 depends on X86_32
255 help
256 The SGI Visual Workstation series is an IA32-based workstation
257 based on SGI systems chips with some legacy PC hardware attached.
258
259 Say Y here to create a kernel to run on the SGI 320 or 540.
260
261 A kernel compiled for the Visual Workstation will not run on PCs
262 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
263
264config X86_GENERICARCH
265 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
266 depends on X86_32
267 help
268 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
269 It is intended for a generic binary kernel.
270 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
271
272config X86_ES7000
273 bool "Support for Unisys ES7000 IA32 series"
274 depends on X86_32 && SMP
275 help
276 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
277 supposed to run on an IA32-based Unisys ES7000 system.
278 Only choose this option if you have such a system, otherwise you
279 should say N here.
280
281config X86_VSMP
282 bool "Support for ScaleMP vSMP"
283 depends on X86_64 && PCI
284 help
285 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
286 supposed to run on these EM64T-based machines. Only choose this option
287 if you have one of these machines.
288
289endchoice
290
291config SCHED_NO_NO_OMIT_FRAME_POINTER
292 bool "Single-depth WCHAN output"
293 default y
294 depends on X86_32
295 help
296 Calculate simpler /proc/<PID>/wchan values. If this option
297 is disabled then wchan values will recurse back to the
298 caller function. This provides more accurate wchan values,
299 at the expense of slightly more scheduling overhead.
300
301 If in doubt, say "Y".
302
303config PARAVIRT
304 bool
305 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
306 help
307 This changes the kernel so it can modify itself when it is run
308 under a hypervisor, potentially improving performance significantly
309 over full virtualization. However, when run without a hypervisor
310 the kernel is theoretically slower and slightly larger.
311
312menuconfig PARAVIRT_GUEST
313 bool "Paravirtualized guest support"
314 depends on X86_32
315 help
316 Say Y here to get to see options related to running Linux under
317 various hypervisors. This option alone does not add any kernel code.
318
319 If you say N, all options in this submenu will be skipped and disabled.
320
321if PARAVIRT_GUEST
322
323source "arch/x86/xen/Kconfig"
324
325config VMI
326 bool "VMI Guest support"
327 select PARAVIRT
328 depends on !(X86_VISWS || X86_VOYAGER)
329 help
330 VMI provides a paravirtualized interface to the VMware ESX server
331 (it could be used by other hypervisors in theory too, but is not
332 at the moment), by linking the kernel to a GPL-ed ROM module
333 provided by the hypervisor.
334
335source "arch/x86/lguest/Kconfig"
336
337endif
338
339config ACPI_SRAT
340 bool
341 default y
342 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
343 select ACPI_NUMA
344
345config HAVE_ARCH_PARSE_SRAT
346 bool
347 default y
348 depends on ACPI_SRAT
349
350config X86_SUMMIT_NUMA
351 bool
352 default y
353 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
354
355config X86_CYCLONE_TIMER
356 bool
357 default y
358 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
359
360config ES7000_CLUSTERED_APIC
361 bool
362 default y
363 depends on SMP && X86_ES7000 && MPENTIUMIII
364
365source "arch/x86/Kconfig.cpu"
366
367config HPET_TIMER
368 bool
369 prompt "HPET Timer Support" if X86_32
370 default X86_64
371 help
372 Use the IA-PC HPET (High Precision Event Timer) to manage
373 time in preference to the PIT and RTC, if a HPET is
374 present.
375 HPET is the next generation timer replacing legacy 8254s.
376 The HPET provides a stable time base on SMP
377 systems, unlike the TSC, but it is more expensive to access,
378 as it is off-chip. You can find the HPET spec at
379 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
380
381 You can safely choose Y here. However, HPET will only be
382 activated if the platform and the BIOS support this feature.
383 Otherwise the 8254 will be used for timing services.
384
385 Choose N to continue using the legacy 8254 timer.
386
387config HPET_EMULATE_RTC
388 bool
389 depends on HPET_TIMER && RTC=y
390 default y
391
392# Mark as embedded because too many people got it wrong.
393# The code disables itself when not needed.
394config GART_IOMMU
395 bool "GART IOMMU support" if EMBEDDED
396 default y
397 select SWIOTLB
398 select AGP
399 depends on X86_64 && PCI
400 help
401 Support for full DMA access of devices with 32bit memory access only
402 on systems with more than 3GB. This is usually needed for USB,
403 sound, many IDE/SATA chipsets and some other devices.
404 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
405 based hardware IOMMU and a software bounce buffer based IOMMU used
406 on Intel systems and as fallback.
407 The code is only active when needed (enough memory and limited
408 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
409 too.
410
411config CALGARY_IOMMU
412 bool "IBM Calgary IOMMU support"
413 select SWIOTLB
414 depends on X86_64 && PCI && EXPERIMENTAL
415 help
416 Support for hardware IOMMUs in IBM's xSeries x366 and x460
417 systems. Needed to run systems with more than 3GB of memory
418 properly with 32-bit PCI devices that do not support DAC
419 (Double Address Cycle). Calgary also supports bus level
420 isolation, where all DMAs pass through the IOMMU. This
421 prevents them from going anywhere except their intended
422 destination. This catches hard-to-find kernel bugs and
423 mis-behaving drivers and devices that do not use the DMA-API
424 properly to set up their DMA buffers. The IOMMU can be
425 turned off at boot time with the iommu=off parameter.
426 Normally the kernel will make the right choice by itself.
427 If unsure, say Y.
428
429config CALGARY_IOMMU_ENABLED_BY_DEFAULT
430 bool "Should Calgary be enabled by default?"
431 default y
432 depends on CALGARY_IOMMU
433 help
434 Should Calgary be enabled by default? if you choose 'y', Calgary
435 will be used (if it exists). If you choose 'n', Calgary will not be
436 used even if it exists. If you choose 'n' and would like to use
437 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
438 If unsure, say Y.
439
440# need this always selected by IOMMU for the VIA workaround
441config SWIOTLB
442 bool
443 help
444 Support for software bounce buffers used on x86-64 systems
445 which don't have a hardware IOMMU (e.g. the current generation
446 of Intel's x86-64 CPUs). Using this PCI devices which can only
447 access 32-bits of memory can be used on systems with more than
448 3 GB of memory. If unsure, say Y.
449
450
451config NR_CPUS
452 int "Maximum number of CPUs (2-255)"
453 range 2 255
454 depends on SMP
455 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
456 default "8"
457 help
458 This allows you to specify the maximum number of CPUs which this
459 kernel will support. The maximum supported value is 255 and the
460 minimum value which makes sense is 2.
461
462 This is purely to save memory - each supported CPU adds
463 approximately eight kilobytes to the kernel image.
464
465config SCHED_SMT
466 bool "SMT (Hyperthreading) scheduler support"
467 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
468 help
469 SMT scheduler support improves the CPU scheduler's decision making
470 when dealing with Intel Pentium 4 chips with HyperThreading at a
471 cost of slightly increased overhead in some places. If unsure say
472 N here.
473
474config SCHED_MC
475 bool "Multi-core scheduler support"
476 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
477 default y
478 help
479 Multi-core scheduler support improves the CPU scheduler's decision
480 making when dealing with multi-core CPU chips at a cost of slightly
481 increased overhead in some places. If unsure say N here.
482
483source "kernel/Kconfig.preempt"
484
485config X86_UP_APIC
486 bool "Local APIC support on uniprocessors"
487 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
488 help
489 A local APIC (Advanced Programmable Interrupt Controller) is an
490 integrated interrupt controller in the CPU. If you have a single-CPU
491 system which has a processor with a local APIC, you can say Y here to
492 enable and use it. If you say Y here even though your machine doesn't
493 have a local APIC, then the kernel will still run with no slowdown at
494 all. The local APIC supports CPU-generated self-interrupts (timer,
495 performance counters), and the NMI watchdog which detects hard
496 lockups.
497
498config X86_UP_IOAPIC
499 bool "IO-APIC support on uniprocessors"
500 depends on X86_UP_APIC
501 help
502 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
503 SMP-capable replacement for PC-style interrupt controllers. Most
504 SMP systems and many recent uniprocessor systems have one.
505
506 If you have a single-CPU system with an IO-APIC, you can say Y here
507 to use it. If you say Y here even though your machine doesn't have
508 an IO-APIC, then the kernel will still run with no slowdown at all.
509
510config X86_LOCAL_APIC
511 bool
512 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
513 default y
514
515config X86_IO_APIC
516 bool
517 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
518 default y
519
520config X86_VISWS_APIC
521 bool
522 depends on X86_32 && X86_VISWS
523 default y
524
525config X86_MCE
526 bool "Machine Check Exception"
527 depends on !X86_VOYAGER
528 ---help---
529 Machine Check Exception support allows the processor to notify the
530 kernel if it detects a problem (e.g. overheating, component failure).
531 The action the kernel takes depends on the severity of the problem,
532 ranging from a warning message on the console, to halting the machine.
533 Your processor must be a Pentium or newer to support this - check the
534 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
535 have a design flaw which leads to false MCE events - hence MCE is
536 disabled on all P5 processors, unless explicitly enabled with "mce"
537 as a boot argument. Similarly, if MCE is built in and creates a
538 problem on some new non-standard machine, you can boot with "nomce"
539 to disable it. MCE support simply ignores non-MCE processors like
540 the 386 and 486, so nearly everyone can say Y here.
541
542config X86_MCE_INTEL
543 bool "Intel MCE features"
544 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
545 default y
546 help
547 Additional support for intel specific MCE features such as
548 the thermal monitor.
549
550config X86_MCE_AMD
551 bool "AMD MCE features"
552 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
553 default y
554 help
555 Additional support for AMD specific MCE features such as
556 the DRAM Error Threshold.
557
558config X86_MCE_NONFATAL
559 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
560 depends on X86_32 && X86_MCE
561 help
562 Enabling this feature starts a timer that triggers every 5 seconds which
563 will look at the machine check registers to see if anything happened.
564 Non-fatal problems automatically get corrected (but still logged).
565 Disable this if you don't want to see these messages.
566 Seeing the messages this option prints out may be indicative of dying
567 or out-of-spec (ie, overclocked) hardware.
568 This option only does something on certain CPUs.
569 (AMD Athlon/Duron and Intel Pentium 4)
570
571config X86_MCE_P4THERMAL
572 bool "check for P4 thermal throttling interrupt."
573 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
574 help
575 Enabling this feature will cause a message to be printed when the P4
576 enters thermal throttling.
577
578config VM86
579 bool "Enable VM86 support" if EMBEDDED
580 default y
581 depends on X86_32
582 help
583 This option is required by programs like DOSEMU to run 16-bit legacy
584 code on X86 processors. It also may be needed by software like
585 XFree86 to initialize some video cards via BIOS. Disabling this
586 option saves about 6k.
587
588config TOSHIBA
589 tristate "Toshiba Laptop support"
590 depends on X86_32
591 ---help---
592 This adds a driver to safely access the System Management Mode of
593 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
594 not work on models with a Phoenix BIOS. The System Management Mode
595 is used to set the BIOS and power saving options on Toshiba portables.
596
597 For information on utilities to make use of this driver see the
598 Toshiba Linux utilities web site at:
599 <http://www.buzzard.org.uk/toshiba/>.
600
601 Say Y if you intend to run this kernel on a Toshiba portable.
602 Say N otherwise.
603
604config I8K
605 tristate "Dell laptop support"
606 depends on X86_32
607 ---help---
608 This adds a driver to safely access the System Management Mode
609 of the CPU on the Dell Inspiron 8000. The System Management Mode
610 is used to read cpu temperature and cooling fan status and to
611 control the fans on the I8K portables.
612
613 This driver has been tested only on the Inspiron 8000 but it may
614 also work with other Dell laptops. You can force loading on other
615 models by passing the parameter `force=1' to the module. Use at
616 your own risk.
617
618 For information on utilities to make use of this driver see the
619 I8K Linux utilities web site at:
620 <http://people.debian.org/~dz/i8k/>
621
622 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
623 Say N otherwise.
624
625config X86_REBOOTFIXUPS
626 bool "Enable X86 board specific fixups for reboot"
627 depends on X86_32 && X86
628 default n
629 ---help---
630 This enables chipset and/or board specific fixups to be done
631 in order to get reboot to work correctly. This is only needed on
632 some combinations of hardware and BIOS. The symptom, for which
633 this config is intended, is when reboot ends with a stalled/hung
634 system.
635
636 Currently, the only fixup is for the Geode machines using
637 CS5530A and CS5536 chipsets.
638
639 Say Y if you want to enable the fixup. Currently, it's safe to
640 enable this option even if you don't need it.
641 Say N otherwise.
642
643config MICROCODE
644 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
645 select FW_LOADER
646 ---help---
647 If you say Y here, you will be able to update the microcode on
648 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
649 Pentium III, Pentium 4, Xeon etc. You will obviously need the
650 actual microcode binary data itself which is not shipped with the
651 Linux kernel.
652
653 For latest news and information on obtaining all the required
654 ingredients for this driver, check:
655 <http://www.urbanmyth.org/microcode/>.
656
657 To compile this driver as a module, choose M here: the
658 module will be called microcode.
659
660config MICROCODE_OLD_INTERFACE
661 bool
662 depends on MICROCODE
663 default y
664
665config X86_MSR
666 tristate "/dev/cpu/*/msr - Model-specific register support"
667 help
668 This device gives privileged processes access to the x86
669 Model-Specific Registers (MSRs). It is a character device with
670 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
671 MSR accesses are directed to a specific CPU on multi-processor
672 systems.
673
674config X86_CPUID
675 tristate "/dev/cpu/*/cpuid - CPU information support"
676 help
677 This device gives processes access to the x86 CPUID instruction to
678 be executed on a specific processor. It is a character device
679 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
680 /dev/cpu/31/cpuid.
681
682choice
683 prompt "High Memory Support"
684 default HIGHMEM4G if !X86_NUMAQ
685 default HIGHMEM64G if X86_NUMAQ
686 depends on X86_32
687
688config NOHIGHMEM
689 bool "off"
690 depends on !X86_NUMAQ
691 ---help---
692 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
693 However, the address space of 32-bit x86 processors is only 4
694 Gigabytes large. That means that, if you have a large amount of
695 physical memory, not all of it can be "permanently mapped" by the
696 kernel. The physical memory that's not permanently mapped is called
697 "high memory".
698
699 If you are compiling a kernel which will never run on a machine with
700 more than 1 Gigabyte total physical RAM, answer "off" here (default
701 choice and suitable for most users). This will result in a "3GB/1GB"
702 split: 3GB are mapped so that each process sees a 3GB virtual memory
703 space and the remaining part of the 4GB virtual memory space is used
704 by the kernel to permanently map as much physical memory as
705 possible.
706
707 If the machine has between 1 and 4 Gigabytes physical RAM, then
708 answer "4GB" here.
709
710 If more than 4 Gigabytes is used then answer "64GB" here. This
711 selection turns Intel PAE (Physical Address Extension) mode on.
712 PAE implements 3-level paging on IA32 processors. PAE is fully
713 supported by Linux, PAE mode is implemented on all recent Intel
714 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
715 then the kernel will not boot on CPUs that don't support PAE!
716
717 The actual amount of total physical memory will either be
718 auto detected or can be forced by using a kernel command line option
719 such as "mem=256M". (Try "man bootparam" or see the documentation of
720 your boot loader (lilo or loadlin) about how to pass options to the
721 kernel at boot time.)
722
723 If unsure, say "off".
724
725config HIGHMEM4G
726 bool "4GB"
727 depends on !X86_NUMAQ
728 help
729 Select this if you have a 32-bit processor and between 1 and 4
730 gigabytes of physical RAM.
731
732config HIGHMEM64G
733 bool "64GB"
734 depends on !M386 && !M486
735 select X86_PAE
736 help
737 Select this if you have a 32-bit processor and more than 4
738 gigabytes of physical RAM.
739
740endchoice
741
742choice
743 depends on EXPERIMENTAL
744 prompt "Memory split" if EMBEDDED
745 default VMSPLIT_3G
746 depends on X86_32
747 help
748 Select the desired split between kernel and user memory.
749
750 If the address range available to the kernel is less than the
751 physical memory installed, the remaining memory will be available
752 as "high memory". Accessing high memory is a little more costly
753 than low memory, as it needs to be mapped into the kernel first.
754 Note that increasing the kernel address space limits the range
755 available to user programs, making the address space there
756 tighter. Selecting anything other than the default 3G/1G split
757 will also likely make your kernel incompatible with binary-only
758 kernel modules.
759
760 If you are not absolutely sure what you are doing, leave this
761 option alone!
762
763 config VMSPLIT_3G
764 bool "3G/1G user/kernel split"
765 config VMSPLIT_3G_OPT
766 depends on !X86_PAE
767 bool "3G/1G user/kernel split (for full 1G low memory)"
768 config VMSPLIT_2G
769 bool "2G/2G user/kernel split"
770 config VMSPLIT_2G_OPT
771 depends on !X86_PAE
772 bool "2G/2G user/kernel split (for full 2G low memory)"
773 config VMSPLIT_1G
774 bool "1G/3G user/kernel split"
775endchoice
776
777config PAGE_OFFSET
778 hex
779 default 0xB0000000 if VMSPLIT_3G_OPT
780 default 0x80000000 if VMSPLIT_2G
781 default 0x78000000 if VMSPLIT_2G_OPT
782 default 0x40000000 if VMSPLIT_1G
783 default 0xC0000000
784 depends on X86_32
785
786config HIGHMEM
787 bool
788 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
789 default y
790
791config X86_PAE
792 bool "PAE (Physical Address Extension) Support"
793 default n
794 depends on X86_32 && !HIGHMEM4G
795 select RESOURCES_64BIT
796 help
797 PAE is required for NX support, and furthermore enables
798 larger swapspace support for non-overcommit purposes. It
799 has the cost of more pagetable lookup overhead, and also
800 consumes more pagetable space per process.
801
802# Common NUMA Features
803config NUMA
804 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
805 depends on SMP
806 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
807 default n if X86_PC
808 default y if (X86_NUMAQ || X86_SUMMIT)
809 help
810 Enable NUMA (Non Uniform Memory Access) support.
811 The kernel will try to allocate memory used by a CPU on the
812 local memory controller of the CPU and add some more
813 NUMA awareness to the kernel.
814
815 For i386 this is currently highly experimental and should be only
816 used for kernel development. It might also cause boot failures.
817 For x86_64 this is recommended on all multiprocessor Opteron systems.
818 If the system is EM64T, you should say N unless your system is
819 EM64T NUMA.
820
821comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
822 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
823
824config K8_NUMA
825 bool "Old style AMD Opteron NUMA detection"
826 depends on X86_64 && NUMA && PCI
827 default y
828 help
829 Enable K8 NUMA node topology detection. You should say Y here if
830 you have a multi processor AMD K8 system. This uses an old
831 method to read the NUMA configuration directly from the builtin
832 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
833 instead, which also takes priority if both are compiled in.
834
835config X86_64_ACPI_NUMA
836 bool "ACPI NUMA detection"
837 depends on X86_64 && NUMA && ACPI && PCI
838 select ACPI_NUMA
839 default y
840 help
841 Enable ACPI SRAT based node topology detection.
842
843config NUMA_EMU
844 bool "NUMA emulation"
845 depends on X86_64 && NUMA
846 help
847 Enable NUMA emulation. A flat machine will be split
848 into virtual nodes when booted with "numa=fake=N", where N is the
849 number of nodes. This is only useful for debugging.
850
851config NODES_SHIFT
852 int
853 default "6" if X86_64
854 default "4" if X86_NUMAQ
855 default "3"
856 depends on NEED_MULTIPLE_NODES
857
858config HAVE_ARCH_BOOTMEM_NODE
859 bool
860 depends on X86_32 && NUMA
861 default y
862
863config ARCH_HAVE_MEMORY_PRESENT
864 bool
865 depends on X86_32 && DISCONTIGMEM
866 default y
867
868config NEED_NODE_MEMMAP_SIZE
869 bool
870 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
871 default y
872
873config HAVE_ARCH_ALLOC_REMAP
874 bool
875 depends on X86_32 && NUMA
876 default y
877
878config ARCH_FLATMEM_ENABLE
879 def_bool y
880 depends on (X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC) || (X86_64 && !NUMA)
881
882config ARCH_DISCONTIGMEM_ENABLE
883 def_bool y
884 depends on NUMA
885
886config ARCH_DISCONTIGMEM_DEFAULT
887 def_bool y
888 depends on NUMA
889
890config ARCH_SPARSEMEM_ENABLE
891 def_bool y
892 depends on NUMA || (EXPERIMENTAL && (X86_PC || X86_64))
893 select SPARSEMEM_STATIC if X86_32
894 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
895
896config ARCH_SELECT_MEMORY_MODEL
897 def_bool y
898 depends on X86_32 && ARCH_SPARSEMEM_ENABLE
899
900config ARCH_MEMORY_PROBE
901 def_bool X86_64
902 depends on MEMORY_HOTPLUG
903
904source "mm/Kconfig"
905
906config HIGHPTE
907 bool "Allocate 3rd-level pagetables from highmem"
908 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
909 help
910 The VM uses one page table entry for each page of physical memory.
911 For systems with a lot of RAM, this can be wasteful of precious
912 low memory. Setting this option will put user-space page table
913 entries in high memory.
914
915config MATH_EMULATION
916 bool
917 prompt "Math emulation" if X86_32
918 ---help---
919 Linux can emulate a math coprocessor (used for floating point
920 operations) if you don't have one. 486DX and Pentium processors have
921 a math coprocessor built in, 486SX and 386 do not, unless you added
922 a 487DX or 387, respectively. (The messages during boot time can
923 give you some hints here ["man dmesg"].) Everyone needs either a
924 coprocessor or this emulation.
925
926 If you don't have a math coprocessor, you need to say Y here; if you
927 say Y here even though you have a coprocessor, the coprocessor will
928 be used nevertheless. (This behavior can be changed with the kernel
929 command line option "no387", which comes handy if your coprocessor
930 is broken. Try "man bootparam" or see the documentation of your boot
931 loader (lilo or loadlin) about how to pass options to the kernel at
932 boot time.) This means that it is a good idea to say Y here if you
933 intend to use this kernel on different machines.
934
935 More information about the internals of the Linux math coprocessor
936 emulation can be found in <file:arch/x86/math-emu/README>.
937
938 If you are not sure, say Y; apart from resulting in a 66 KB bigger
939 kernel, it won't hurt.
940
941config MTRR
942 bool "MTRR (Memory Type Range Register) support"
943 ---help---
944 On Intel P6 family processors (Pentium Pro, Pentium II and later)
945 the Memory Type Range Registers (MTRRs) may be used to control
946 processor access to memory ranges. This is most useful if you have
947 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
948 allows bus write transfers to be combined into a larger transfer
949 before bursting over the PCI/AGP bus. This can increase performance
950 of image write operations 2.5 times or more. Saying Y here creates a
951 /proc/mtrr file which may be used to manipulate your processor's
952 MTRRs. Typically the X server should use this.
953
954 This code has a reasonably generic interface so that similar
955 control registers on other processors can be easily supported
956 as well:
957
958 The Cyrix 6x86, 6x86MX and M II processors have Address Range
959 Registers (ARRs) which provide a similar functionality to MTRRs. For
960 these, the ARRs are used to emulate the MTRRs.
961 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
962 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
963 write-combining. All of these processors are supported by this code
964 and it makes sense to say Y here if you have one of them.
965
966 Saying Y here also fixes a problem with buggy SMP BIOSes which only
967 set the MTRRs for the boot CPU and not for the secondary CPUs. This
968 can lead to all sorts of problems, so it's good to say Y here.
969
970 You can safely say Y even if your machine doesn't have MTRRs, you'll
971 just add about 9 KB to your kernel.
972
973 See <file:Documentation/mtrr.txt> for more information.
974
975config EFI
976 bool "Boot from EFI support"
977 depends on X86_32 && ACPI
978 default n
979 ---help---
980 This enables the kernel to boot on EFI platforms using
981 system configuration information passed to it from the firmware.
982 This also enables the kernel to use any EFI runtime services that are
983 available (such as the EFI variable services).
984
985 This option is only useful on systems that have EFI firmware
986 and will result in a kernel image that is ~8k larger. In addition,
987 you must use the latest ELILO loader available at
988 <http://elilo.sourceforge.net> in order to take advantage of
989 kernel initialization using EFI information (neither GRUB nor LILO know
990 anything about EFI). However, even with this option, the resultant
991 kernel should continue to boot on existing non-EFI platforms.
992
993config IRQBALANCE
994 bool "Enable kernel irq balancing"
995 depends on X86_32 && SMP && X86_IO_APIC
996 default y
997 help
998 The default yes will allow the kernel to do irq load balancing.
999 Saying no will keep the kernel from doing irq load balancing.
1000
1001# turning this on wastes a bunch of space.
1002# Summit needs it only when NUMA is on
1003config BOOT_IOREMAP
1004 bool
1005 depends on X86_32 && (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
1006 default y
1007
1008config SECCOMP
1009 bool "Enable seccomp to safely compute untrusted bytecode"
1010 depends on PROC_FS
1011 default y
1012 help
1013 This kernel feature is useful for number crunching applications
1014 that may need to compute untrusted bytecode during their
1015 execution. By using pipes or other transports made available to
1016 the process as file descriptors supporting the read/write
1017 syscalls, it's possible to isolate those applications in
1018 their own address space using seccomp. Once seccomp is
1019 enabled via /proc/<pid>/seccomp, it cannot be disabled
1020 and the task is only allowed to execute a few safe syscalls
1021 defined by each seccomp mode.
1022
1023 If unsure, say Y. Only embedded should say N here.
1024
1025config CC_STACKPROTECTOR
1026 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1027 depends on X86_64 && EXPERIMENTAL
1028 help
1029 This option turns on the -fstack-protector GCC feature. This
1030 feature puts, at the beginning of critical functions, a canary
1031 value on the stack just before the return address, and validates
1032 the value just before actually returning. Stack based buffer
1033 overflows (that need to overwrite this return address) now also
1034 overwrite the canary, which gets detected and the attack is then
1035 neutralized via a kernel panic.
1036
1037 This feature requires gcc version 4.2 or above, or a distribution
1038 gcc with the feature backported. Older versions are automatically
1039 detected and for those versions, this configuration option is ignored.
1040
1041config CC_STACKPROTECTOR_ALL
1042 bool "Use stack-protector for all functions"
1043 depends on CC_STACKPROTECTOR
1044 help
1045 Normally, GCC only inserts the canary value protection for
1046 functions that use large-ish on-stack buffers. By enabling
1047 this option, GCC will be asked to do this for ALL functions.
1048
1049source kernel/Kconfig.hz
1050
1051config KEXEC
1052 bool "kexec system call"
1053 help
1054 kexec is a system call that implements the ability to shutdown your
1055 current kernel, and to start another kernel. It is like a reboot
1056 but it is independent of the system firmware. And like a reboot
1057 you can start any kernel with it, not just Linux.
1058
1059 The name comes from the similarity to the exec system call.
1060
1061 It is an ongoing process to be certain the hardware in a machine
1062 is properly shutdown, so do not be surprised if this code does not
1063 initially work for you. It may help to enable device hotplugging
1064 support. As of this writing the exact hardware interface is
1065 strongly in flux, so no good recommendation can be made.
1066
1067config CRASH_DUMP
1068 bool "kernel crash dumps (EXPERIMENTAL)"
1069 depends on EXPERIMENTAL
1070 depends on X86_64 || (X86_32 && HIGHMEM)
1071 help
1072 Generate crash dump after being started by kexec.
1073 This should be normally only set in special crash dump kernels
1074 which are loaded in the main kernel with kexec-tools into
1075 a specially reserved region and then later executed after
1076 a crash by kdump/kexec. The crash dump kernel must be compiled
1077 to a memory address not used by the main kernel or BIOS using
1078 PHYSICAL_START, or it must be built as a relocatable image
1079 (CONFIG_RELOCATABLE=y).
1080 For more details see Documentation/kdump/kdump.txt
1081
1082config PHYSICAL_START
1083 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1084 default "0x1000000" if X86_NUMAQ
1085 default "0x200000" if X86_64
1086 default "0x100000"
1087 help
1088 This gives the physical address where the kernel is loaded.
1089
1090 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1091 bzImage will decompress itself to above physical address and
1092 run from there. Otherwise, bzImage will run from the address where
1093 it has been loaded by the boot loader and will ignore above physical
1094 address.
1095
1096 In normal kdump cases one does not have to set/change this option
1097 as now bzImage can be compiled as a completely relocatable image
1098 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1099 address. This option is mainly useful for the folks who don't want
1100 to use a bzImage for capturing the crash dump and want to use a
1101 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1102 to be specifically compiled to run from a specific memory area
1103 (normally a reserved region) and this option comes handy.
1104
1105 So if you are using bzImage for capturing the crash dump, leave
1106 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1107 Otherwise if you plan to use vmlinux for capturing the crash dump
1108 change this value to start of the reserved region (Typically 16MB
1109 0x1000000). In other words, it can be set based on the "X" value as
1110 specified in the "crashkernel=YM@XM" command line boot parameter
1111 passed to the panic-ed kernel. Typically this parameter is set as
1112 crashkernel=64M@16M. Please take a look at
1113 Documentation/kdump/kdump.txt for more details about crash dumps.
1114
1115 Usage of bzImage for capturing the crash dump is recommended as
1116 one does not have to build two kernels. Same kernel can be used
1117 as production kernel and capture kernel. Above option should have
1118 gone away after relocatable bzImage support is introduced. But it
1119 is present because there are users out there who continue to use
1120 vmlinux for dump capture. This option should go away down the
1121 line.
1122
1123 Don't change this unless you know what you are doing.
1124
1125config RELOCATABLE
1126 bool "Build a relocatable kernel (EXPERIMENTAL)"
1127 depends on EXPERIMENTAL
1128 help
1129 This builds a kernel image that retains relocation information
1130 so it can be loaded someplace besides the default 1MB.
1131 The relocations tend to make the kernel binary about 10% larger,
1132 but are discarded at runtime.
1133
1134 One use is for the kexec on panic case where the recovery kernel
1135 must live at a different physical address than the primary
1136 kernel.
1137
1138 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1139 it has been loaded at and the compile time physical address
1140 (CONFIG_PHYSICAL_START) is ignored.
1141
1142config PHYSICAL_ALIGN
1143 hex
1144 prompt "Alignment value to which kernel should be aligned" if X86_32
1145 default "0x100000" if X86_32
1146 default "0x200000" if X86_64
1147 range 0x2000 0x400000
1148 help
1149 This value puts the alignment restrictions on physical address
1150 where kernel is loaded and run from. Kernel is compiled for an
1151 address which meets above alignment restriction.
1152
1153 If bootloader loads the kernel at a non-aligned address and
1154 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1155 address aligned to above value and run from there.
1156
1157 If bootloader loads the kernel at a non-aligned address and
1158 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1159 load address and decompress itself to the address it has been
1160 compiled for and run from there. The address for which kernel is
1161 compiled already meets above alignment restrictions. Hence the
1162 end result is that kernel runs from a physical address meeting
1163 above alignment restrictions.
1164
1165 Don't change this unless you know what you are doing.
1166
1167config HOTPLUG_CPU
1168 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1169 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1170 ---help---
1171 Say Y here to experiment with turning CPUs off and on, and to
1172 enable suspend on SMP systems. CPUs can be controlled through
1173 /sys/devices/system/cpu.
1174 Say N if you want to disable CPU hotplug and don't need to
1175 suspend.
1176
1177config COMPAT_VDSO
1178 bool "Compat VDSO support"
1179 default y
1180 depends on X86_32
1181 help
1182 Map the VDSO to the predictable old-style address too.
1183 ---help---
1184 Say N here if you are running a sufficiently recent glibc
1185 version (2.3.3 or later), to remove the high-mapped
1186 VDSO mapping and to exclusively use the randomized VDSO.
1187
1188 If unsure, say Y.
1189
1190endmenu
1191
1192config ARCH_ENABLE_MEMORY_HOTPLUG
1193 def_bool y
1194 depends on X86_64 || (X86_32 && HIGHMEM)
1195
1196config MEMORY_HOTPLUG_RESERVE
1197 def_bool X86_64
1198 depends on (MEMORY_HOTPLUG && DISCONTIGMEM)
1199
1200config HAVE_ARCH_EARLY_PFN_TO_NID
1201 def_bool X86_64
1202 depends on NUMA
1203
1204config OUT_OF_LINE_PFN_TO_PAGE
1205 def_bool X86_64
1206 depends on DISCONTIGMEM
155 1207
156menu "Power management options" 1208menu "Power management options"
157 depends on !X86_VOYAGER 1209 depends on !X86_VOYAGER
diff --git a/arch/x86/Kconfig.i386 b/arch/x86/Kconfig.i386
index b8b462a91dc7..7b8dc2604d57 100644
--- a/arch/x86/Kconfig.i386
+++ b/arch/x86/Kconfig.i386
@@ -14,1058 +14,5 @@ config X86_32
14 486, 586, Pentiums, and various instruction-set-compatible chips by 14 486, 586, Pentiums, and various instruction-set-compatible chips by
15 AMD, Cyrix, and others. 15 AMD, Cyrix, and others.
16 16
17source "init/Kconfig"
18
19menu "Processor type and features"
20
21source "kernel/time/Kconfig"
22
23config SMP
24 bool "Symmetric multi-processing support"
25 ---help---
26 This enables support for systems with more than one CPU. If you have
27 a system with only one CPU, like most personal computers, say N. If
28 you have a system with more than one CPU, say Y.
29
30 If you say N here, the kernel will run on single and multiprocessor
31 machines, but will use only one CPU of a multiprocessor machine. If
32 you say Y here, the kernel will run on many, but not all,
33 singleprocessor machines. On a singleprocessor machine, the kernel
34 will run faster if you say N here.
35
36 Note that if you say Y here and choose architecture "586" or
37 "Pentium" under "Processor family", the kernel will not work on 486
38 architectures. Similarly, multiprocessor kernels for the "PPro"
39 architecture may not work on all Pentium based boards.
40
41 People using multiprocessor machines who say Y here should also say
42 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
43 Management" code will be disabled if you say Y here.
44
45 See also the <file:Documentation/smp.txt>,
46 <file:Documentation/i386/IO-APIC.txt>,
47 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
48 <http://www.tldp.org/docs.html#howto>.
49
50 If you don't know what to do here, say N.
51
52choice
53 prompt "Subarchitecture Type"
54 default X86_PC
55
56config X86_PC
57 bool "PC-compatible"
58 help
59 Choose this option if your computer is a standard PC or compatible.
60
61config X86_ELAN
62 bool "AMD Elan"
63 depends on X86_32
64 help
65 Select this for an AMD Elan processor.
66
67 Do not use this option for K6/Athlon/Opteron processors!
68
69 If unsure, choose "PC-compatible" instead.
70
71config X86_VOYAGER
72 bool "Voyager (NCR)"
73 depends on X86_32
74 select SMP if !BROKEN
75 help
76 Voyager is an MCA-based 32-way capable SMP architecture proprietary
77 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
78
79 *** WARNING ***
80
81 If you do not specifically know you have a Voyager based machine,
82 say N here, otherwise the kernel you build will not be bootable.
83
84config X86_NUMAQ
85 bool "NUMAQ (IBM/Sequent)"
86 select SMP
87 select NUMA
88 depends on X86_32
89 help
90 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
91 multiquad box. This changes the way that processors are bootstrapped,
92 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
93 You will need a new lynxer.elf file to flash your firmware with - send
94 email to <Martin.Bligh@us.ibm.com>.
95
96config X86_SUMMIT
97 bool "Summit/EXA (IBM x440)"
98 depends on X86_32 && SMP
99 help
100 This option is needed for IBM systems that use the Summit/EXA chipset.
101 In particular, it is needed for the x440.
102
103 If you don't have one of these computers, you should say N here.
104 If you want to build a NUMA kernel, you must select ACPI.
105
106config X86_BIGSMP
107 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
108 depends on X86_32 && SMP
109 help
110 This option is needed for the systems that have more than 8 CPUs
111 and if the system is not of any sub-arch type above.
112
113 If you don't have such a system, you should say N here.
114
115config X86_VISWS
116 bool "SGI 320/540 (Visual Workstation)"
117 depends on X86_32
118 help
119 The SGI Visual Workstation series is an IA32-based workstation
120 based on SGI systems chips with some legacy PC hardware attached.
121
122 Say Y here to create a kernel to run on the SGI 320 or 540.
123
124 A kernel compiled for the Visual Workstation will not run on PCs
125 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
126
127config X86_GENERICARCH
128 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
129 depends on X86_32
130 help
131 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
132 It is intended for a generic binary kernel.
133 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
134
135config X86_ES7000
136 bool "Support for Unisys ES7000 IA32 series"
137 depends on X86_32 && SMP
138 help
139 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
140 supposed to run on an IA32-based Unisys ES7000 system.
141 Only choose this option if you have such a system, otherwise you
142 should say N here.
143
144config X86_VSMP
145 bool "Support for ScaleMP vSMP"
146 depends on X86_64 && PCI
147 help
148 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
149 supposed to run on these EM64T-based machines. Only choose this option
150 if you have one of these machines.
151
152endchoice
153
154config SCHED_NO_NO_OMIT_FRAME_POINTER
155 bool "Single-depth WCHAN output"
156 default y
157 depends on X86_32
158 help
159 Calculate simpler /proc/<PID>/wchan values. If this option
160 is disabled then wchan values will recurse back to the
161 caller function. This provides more accurate wchan values,
162 at the expense of slightly more scheduling overhead.
163
164 If in doubt, say "Y".
165
166config PARAVIRT
167 bool
168 depends on X86_32 && !(X86_VISWS || X86_VOYAGER)
169 help
170 This changes the kernel so it can modify itself when it is run
171 under a hypervisor, potentially improving performance significantly
172 over full virtualization. However, when run without a hypervisor
173 the kernel is theoretically slower and slightly larger.
174
175menuconfig PARAVIRT_GUEST
176 bool "Paravirtualized guest support"
177 depends on X86_32
178 help
179 Say Y here to get to see options related to running Linux under
180 various hypervisors. This option alone does not add any kernel code.
181
182 If you say N, all options in this submenu will be skipped and disabled.
183
184if PARAVIRT_GUEST
185
186source "arch/x86/xen/Kconfig"
187
188config VMI
189 bool "VMI Guest support"
190 select PARAVIRT
191 depends on !(X86_VISWS || X86_VOYAGER)
192 help
193 VMI provides a paravirtualized interface to the VMware ESX server
194 (it could be used by other hypervisors in theory too, but is not
195 at the moment), by linking the kernel to a GPL-ed ROM module
196 provided by the hypervisor.
197
198source "arch/x86/lguest/Kconfig"
199
200endif
201
202config ACPI_SRAT
203 bool
204 default y
205 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
206 select ACPI_NUMA
207
208config HAVE_ARCH_PARSE_SRAT
209 bool
210 default y
211 depends on ACPI_SRAT
212
213config X86_SUMMIT_NUMA
214 bool
215 default y
216 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
217
218config X86_CYCLONE_TIMER
219 bool
220 default y
221 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
222
223config ES7000_CLUSTERED_APIC
224 bool
225 default y
226 depends on SMP && X86_ES7000 && MPENTIUMIII
227
228source "arch/x86/Kconfig.cpu"
229
230config HPET_TIMER
231 bool
232 prompt "HPET Timer Support" if X86_32
233 default X86_64
234 help
235 Use the IA-PC HPET (High Precision Event Timer) to manage
236 time in preference to the PIT and RTC, if a HPET is
237 present.
238 HPET is the next generation timer replacing legacy 8254s.
239 The HPET provides a stable time base on SMP
240 systems, unlike the TSC, but it is more expensive to access,
241 as it is off-chip. You can find the HPET spec at
242 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
243
244 You can safely choose Y here. However, HPET will only be
245 activated if the platform and the BIOS support this feature.
246 Otherwise the 8254 will be used for timing services.
247
248 Choose N to continue using the legacy 8254 timer.
249
250config HPET_EMULATE_RTC
251 bool
252 depends on HPET_TIMER && RTC=y
253 default y
254
255# Mark as embedded because too many people got it wrong.
256# The code disables itself when not needed.
257config GART_IOMMU
258 bool "GART IOMMU support" if EMBEDDED
259 default y
260 select SWIOTLB
261 select AGP
262 depends on X86_64 && PCI
263 help
264 Support for full DMA access of devices with 32bit memory access only
265 on systems with more than 3GB. This is usually needed for USB,
266 sound, many IDE/SATA chipsets and some other devices.
267 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
268 based hardware IOMMU and a software bounce buffer based IOMMU used
269 on Intel systems and as fallback.
270 The code is only active when needed (enough memory and limited
271 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
272 too.
273
274config CALGARY_IOMMU
275 bool "IBM Calgary IOMMU support"
276 select SWIOTLB
277 depends on X86_64 && PCI && EXPERIMENTAL
278 help
279 Support for hardware IOMMUs in IBM's xSeries x366 and x460
280 systems. Needed to run systems with more than 3GB of memory
281 properly with 32-bit PCI devices that do not support DAC
282 (Double Address Cycle). Calgary also supports bus level
283 isolation, where all DMAs pass through the IOMMU. This
284 prevents them from going anywhere except their intended
285 destination. This catches hard-to-find kernel bugs and
286 mis-behaving drivers and devices that do not use the DMA-API
287 properly to set up their DMA buffers. The IOMMU can be
288 turned off at boot time with the iommu=off parameter.
289 Normally the kernel will make the right choice by itself.
290 If unsure, say Y.
291
292config CALGARY_IOMMU_ENABLED_BY_DEFAULT
293 bool "Should Calgary be enabled by default?"
294 default y
295 depends on CALGARY_IOMMU
296 help
297 Should Calgary be enabled by default? if you choose 'y', Calgary
298 will be used (if it exists). If you choose 'n', Calgary will not be
299 used even if it exists. If you choose 'n' and would like to use
300 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
301 If unsure, say Y.
302
303# need this always selected by IOMMU for the VIA workaround
304config SWIOTLB
305 bool
306 help
307 Support for software bounce buffers used on x86-64 systems
308 which don't have a hardware IOMMU (e.g. the current generation
309 of Intel's x86-64 CPUs). Using this PCI devices which can only
310 access 32-bits of memory can be used on systems with more than
311 3 GB of memory. If unsure, say Y.
312
313
314config NR_CPUS
315 int "Maximum number of CPUs (2-255)"
316 range 2 255
317 depends on SMP
318 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
319 default "8"
320 help
321 This allows you to specify the maximum number of CPUs which this
322 kernel will support. The maximum supported value is 255 and the
323 minimum value which makes sense is 2.
324
325 This is purely to save memory - each supported CPU adds
326 approximately eight kilobytes to the kernel image.
327
328config SCHED_SMT
329 bool "SMT (Hyperthreading) scheduler support"
330 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
331 help
332 SMT scheduler support improves the CPU scheduler's decision making
333 when dealing with Intel Pentium 4 chips with HyperThreading at a
334 cost of slightly increased overhead in some places. If unsure say
335 N here.
336
337config SCHED_MC
338 bool "Multi-core scheduler support"
339 depends on (X86_64 && SMP) || (X86_32 && X86_HT)
340 default y
341 help
342 Multi-core scheduler support improves the CPU scheduler's decision
343 making when dealing with multi-core CPU chips at a cost of slightly
344 increased overhead in some places. If unsure say N here.
345
346source "kernel/Kconfig.preempt"
347
348config X86_UP_APIC
349 bool "Local APIC support on uniprocessors"
350 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
351 help
352 A local APIC (Advanced Programmable Interrupt Controller) is an
353 integrated interrupt controller in the CPU. If you have a single-CPU
354 system which has a processor with a local APIC, you can say Y here to
355 enable and use it. If you say Y here even though your machine doesn't
356 have a local APIC, then the kernel will still run with no slowdown at
357 all. The local APIC supports CPU-generated self-interrupts (timer,
358 performance counters), and the NMI watchdog which detects hard
359 lockups.
360
361config X86_UP_IOAPIC
362 bool "IO-APIC support on uniprocessors"
363 depends on X86_UP_APIC
364 help
365 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
366 SMP-capable replacement for PC-style interrupt controllers. Most
367 SMP systems and many recent uniprocessor systems have one.
368
369 If you have a single-CPU system with an IO-APIC, you can say Y here
370 to use it. If you say Y here even though your machine doesn't have
371 an IO-APIC, then the kernel will still run with no slowdown at all.
372
373config X86_LOCAL_APIC
374 bool
375 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
376 default y
377
378config X86_IO_APIC
379 bool
380 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
381 default y
382
383config X86_VISWS_APIC
384 bool
385 depends on X86_32 && X86_VISWS
386 default y
387
388config X86_MCE
389 bool "Machine Check Exception"
390 depends on !X86_VOYAGER
391 ---help---
392 Machine Check Exception support allows the processor to notify the
393 kernel if it detects a problem (e.g. overheating, component failure).
394 The action the kernel takes depends on the severity of the problem,
395 ranging from a warning message on the console, to halting the machine.
396 Your processor must be a Pentium or newer to support this - check the
397 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
398 have a design flaw which leads to false MCE events - hence MCE is
399 disabled on all P5 processors, unless explicitly enabled with "mce"
400 as a boot argument. Similarly, if MCE is built in and creates a
401 problem on some new non-standard machine, you can boot with "nomce"
402 to disable it. MCE support simply ignores non-MCE processors like
403 the 386 and 486, so nearly everyone can say Y here.
404
405config X86_MCE_INTEL
406 bool "Intel MCE features"
407 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
408 default y
409 help
410 Additional support for intel specific MCE features such as
411 the thermal monitor.
412
413config X86_MCE_AMD
414 bool "AMD MCE features"
415 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
416 default y
417 help
418 Additional support for AMD specific MCE features such as
419 the DRAM Error Threshold.
420
421config X86_MCE_NONFATAL
422 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
423 depends on X86_32 && X86_MCE
424 help
425 Enabling this feature starts a timer that triggers every 5 seconds which
426 will look at the machine check registers to see if anything happened.
427 Non-fatal problems automatically get corrected (but still logged).
428 Disable this if you don't want to see these messages.
429 Seeing the messages this option prints out may be indicative of dying
430 or out-of-spec (ie, overclocked) hardware.
431 This option only does something on certain CPUs.
432 (AMD Athlon/Duron and Intel Pentium 4)
433
434config X86_MCE_P4THERMAL
435 bool "check for P4 thermal throttling interrupt."
436 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
437 help
438 Enabling this feature will cause a message to be printed when the P4
439 enters thermal throttling.
440
441config VM86
442 bool "Enable VM86 support" if EMBEDDED
443 default y
444 depends on X86_32
445 help
446 This option is required by programs like DOSEMU to run 16-bit legacy
447 code on X86 processors. It also may be needed by software like
448 XFree86 to initialize some video cards via BIOS. Disabling this
449 option saves about 6k.
450
451config TOSHIBA
452 tristate "Toshiba Laptop support"
453 depends on X86_32
454 ---help---
455 This adds a driver to safely access the System Management Mode of
456 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
457 not work on models with a Phoenix BIOS. The System Management Mode
458 is used to set the BIOS and power saving options on Toshiba portables.
459
460 For information on utilities to make use of this driver see the
461 Toshiba Linux utilities web site at:
462 <http://www.buzzard.org.uk/toshiba/>.
463
464 Say Y if you intend to run this kernel on a Toshiba portable.
465 Say N otherwise.
466
467config I8K
468 tristate "Dell laptop support"
469 depends on X86_32
470 ---help---
471 This adds a driver to safely access the System Management Mode
472 of the CPU on the Dell Inspiron 8000. The System Management Mode
473 is used to read cpu temperature and cooling fan status and to
474 control the fans on the I8K portables.
475
476 This driver has been tested only on the Inspiron 8000 but it may
477 also work with other Dell laptops. You can force loading on other
478 models by passing the parameter `force=1' to the module. Use at
479 your own risk.
480
481 For information on utilities to make use of this driver see the
482 I8K Linux utilities web site at:
483 <http://people.debian.org/~dz/i8k/>
484
485 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
486 Say N otherwise.
487
488config X86_REBOOTFIXUPS
489 bool "Enable X86 board specific fixups for reboot"
490 depends on X86_32 && X86
491 default n
492 ---help---
493 This enables chipset and/or board specific fixups to be done
494 in order to get reboot to work correctly. This is only needed on
495 some combinations of hardware and BIOS. The symptom, for which
496 this config is intended, is when reboot ends with a stalled/hung
497 system.
498
499 Currently, the only fixup is for the Geode machines using
500 CS5530A and CS5536 chipsets.
501
502 Say Y if you want to enable the fixup. Currently, it's safe to
503 enable this option even if you don't need it.
504 Say N otherwise.
505
506config MICROCODE
507 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
508 select FW_LOADER
509 ---help---
510 If you say Y here, you will be able to update the microcode on
511 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
512 Pentium III, Pentium 4, Xeon etc. You will obviously need the
513 actual microcode binary data itself which is not shipped with the
514 Linux kernel.
515
516 For latest news and information on obtaining all the required
517 ingredients for this driver, check:
518 <http://www.urbanmyth.org/microcode/>.
519
520 To compile this driver as a module, choose M here: the
521 module will be called microcode.
522
523config MICROCODE_OLD_INTERFACE
524 bool
525 depends on MICROCODE
526 default y
527
528config X86_MSR
529 tristate "/dev/cpu/*/msr - Model-specific register support"
530 help
531 This device gives privileged processes access to the x86
532 Model-Specific Registers (MSRs). It is a character device with
533 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
534 MSR accesses are directed to a specific CPU on multi-processor
535 systems.
536
537config X86_CPUID
538 tristate "/dev/cpu/*/cpuid - CPU information support"
539 help
540 This device gives processes access to the x86 CPUID instruction to
541 be executed on a specific processor. It is a character device
542 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
543 /dev/cpu/31/cpuid.
544
545choice
546 prompt "High Memory Support"
547 default HIGHMEM4G if !X86_NUMAQ
548 default HIGHMEM64G if X86_NUMAQ
549 depends on X86_32
550
551config NOHIGHMEM
552 bool "off"
553 depends on !X86_NUMAQ
554 ---help---
555 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
556 However, the address space of 32-bit x86 processors is only 4
557 Gigabytes large. That means that, if you have a large amount of
558 physical memory, not all of it can be "permanently mapped" by the
559 kernel. The physical memory that's not permanently mapped is called
560 "high memory".
561
562 If you are compiling a kernel which will never run on a machine with
563 more than 1 Gigabyte total physical RAM, answer "off" here (default
564 choice and suitable for most users). This will result in a "3GB/1GB"
565 split: 3GB are mapped so that each process sees a 3GB virtual memory
566 space and the remaining part of the 4GB virtual memory space is used
567 by the kernel to permanently map as much physical memory as
568 possible.
569
570 If the machine has between 1 and 4 Gigabytes physical RAM, then
571 answer "4GB" here.
572
573 If more than 4 Gigabytes is used then answer "64GB" here. This
574 selection turns Intel PAE (Physical Address Extension) mode on.
575 PAE implements 3-level paging on IA32 processors. PAE is fully
576 supported by Linux, PAE mode is implemented on all recent Intel
577 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
578 then the kernel will not boot on CPUs that don't support PAE!
579
580 The actual amount of total physical memory will either be
581 auto detected or can be forced by using a kernel command line option
582 such as "mem=256M". (Try "man bootparam" or see the documentation of
583 your boot loader (lilo or loadlin) about how to pass options to the
584 kernel at boot time.)
585
586 If unsure, say "off".
587
588config HIGHMEM4G
589 bool "4GB"
590 depends on !X86_NUMAQ
591 help
592 Select this if you have a 32-bit processor and between 1 and 4
593 gigabytes of physical RAM.
594
595config HIGHMEM64G
596 bool "64GB"
597 depends on !M386 && !M486
598 select X86_PAE
599 help
600 Select this if you have a 32-bit processor and more than 4
601 gigabytes of physical RAM.
602
603endchoice
604
605choice
606 depends on EXPERIMENTAL
607 prompt "Memory split" if EMBEDDED
608 default VMSPLIT_3G
609 depends on X86_32
610 help
611 Select the desired split between kernel and user memory.
612
613 If the address range available to the kernel is less than the
614 physical memory installed, the remaining memory will be available
615 as "high memory". Accessing high memory is a little more costly
616 than low memory, as it needs to be mapped into the kernel first.
617 Note that increasing the kernel address space limits the range
618 available to user programs, making the address space there
619 tighter. Selecting anything other than the default 3G/1G split
620 will also likely make your kernel incompatible with binary-only
621 kernel modules.
622
623 If you are not absolutely sure what you are doing, leave this
624 option alone!
625
626 config VMSPLIT_3G
627 bool "3G/1G user/kernel split"
628 config VMSPLIT_3G_OPT
629 depends on !X86_PAE
630 bool "3G/1G user/kernel split (for full 1G low memory)"
631 config VMSPLIT_2G
632 bool "2G/2G user/kernel split"
633 config VMSPLIT_2G_OPT
634 depends on !X86_PAE
635 bool "2G/2G user/kernel split (for full 2G low memory)"
636 config VMSPLIT_1G
637 bool "1G/3G user/kernel split"
638endchoice
639
640config PAGE_OFFSET
641 hex
642 default 0xB0000000 if VMSPLIT_3G_OPT
643 default 0x80000000 if VMSPLIT_2G
644 default 0x78000000 if VMSPLIT_2G_OPT
645 default 0x40000000 if VMSPLIT_1G
646 default 0xC0000000
647 depends on X86_32
648
649config HIGHMEM
650 bool
651 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
652 default y
653
654config X86_PAE
655 bool "PAE (Physical Address Extension) Support"
656 default n
657 depends on X86_32 && !HIGHMEM4G
658 select RESOURCES_64BIT
659 help
660 PAE is required for NX support, and furthermore enables
661 larger swapspace support for non-overcommit purposes. It
662 has the cost of more pagetable lookup overhead, and also
663 consumes more pagetable space per process.
664
665# Common NUMA Features
666config NUMA
667 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
668 depends on SMP
669 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
670 default n if X86_PC
671 default y if (X86_NUMAQ || X86_SUMMIT)
672 help
673 Enable NUMA (Non Uniform Memory Access) support.
674 The kernel will try to allocate memory used by a CPU on the
675 local memory controller of the CPU and add some more
676 NUMA awareness to the kernel.
677
678 For i386 this is currently highly experimental and should be only
679 used for kernel development. It might also cause boot failures.
680 For x86_64 this is recommended on all multiprocessor Opteron systems.
681 If the system is EM64T, you should say N unless your system is
682 EM64T NUMA.
683
684comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
685 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
686
687config K8_NUMA
688 bool "Old style AMD Opteron NUMA detection"
689 depends on X86_64 && NUMA && PCI
690 default y
691 help
692 Enable K8 NUMA node topology detection. You should say Y here if
693 you have a multi processor AMD K8 system. This uses an old
694 method to read the NUMA configuration directly from the builtin
695 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
696 instead, which also takes priority if both are compiled in.
697
698config X86_64_ACPI_NUMA
699 bool "ACPI NUMA detection"
700 depends on X86_64 && NUMA && ACPI && PCI
701 select ACPI_NUMA
702 default y
703 help
704 Enable ACPI SRAT based node topology detection.
705
706config NUMA_EMU
707 bool "NUMA emulation"
708 depends on X86_64 && NUMA
709 help
710 Enable NUMA emulation. A flat machine will be split
711 into virtual nodes when booted with "numa=fake=N", where N is the
712 number of nodes. This is only useful for debugging.
713
714config NODES_SHIFT
715 int
716 default "6" if X86_64
717 default "4" if X86_NUMAQ
718 default "3"
719 depends on NEED_MULTIPLE_NODES
720
721config HAVE_ARCH_BOOTMEM_NODE
722 bool
723 depends on X86_32 && NUMA
724 default y
725
726config ARCH_HAVE_MEMORY_PRESENT
727 bool
728 depends on X86_32 && DISCONTIGMEM
729 default y
730
731config NEED_NODE_MEMMAP_SIZE
732 bool
733 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
734 default y
735
736config HAVE_ARCH_ALLOC_REMAP
737 bool
738 depends on X86_32 && NUMA
739 default y
740
741config ARCH_FLATMEM_ENABLE
742 def_bool y
743 depends on (X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC) || (X86_64 && !NUMA)
744
745config ARCH_DISCONTIGMEM_ENABLE
746 def_bool y
747 depends on NUMA
748
749config ARCH_DISCONTIGMEM_DEFAULT
750 def_bool y
751 depends on NUMA
752
753config ARCH_SPARSEMEM_ENABLE
754 def_bool y
755 depends on NUMA || (EXPERIMENTAL && (X86_PC || X86_64))
756 select SPARSEMEM_STATIC if X86_32
757 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
758
759config ARCH_SELECT_MEMORY_MODEL
760 def_bool y
761 depends on X86_32 && ARCH_SPARSEMEM_ENABLE
762
763config ARCH_MEMORY_PROBE
764 def_bool X86_64
765 depends on MEMORY_HOTPLUG
766
767source "mm/Kconfig"
768
769config HIGHPTE
770 bool "Allocate 3rd-level pagetables from highmem"
771 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
772 help
773 The VM uses one page table entry for each page of physical memory.
774 For systems with a lot of RAM, this can be wasteful of precious
775 low memory. Setting this option will put user-space page table
776 entries in high memory.
777
778config MATH_EMULATION
779 bool
780 prompt "Math emulation" if X86_32
781 ---help---
782 Linux can emulate a math coprocessor (used for floating point
783 operations) if you don't have one. 486DX and Pentium processors have
784 a math coprocessor built in, 486SX and 386 do not, unless you added
785 a 487DX or 387, respectively. (The messages during boot time can
786 give you some hints here ["man dmesg"].) Everyone needs either a
787 coprocessor or this emulation.
788
789 If you don't have a math coprocessor, you need to say Y here; if you
790 say Y here even though you have a coprocessor, the coprocessor will
791 be used nevertheless. (This behavior can be changed with the kernel
792 command line option "no387", which comes handy if your coprocessor
793 is broken. Try "man bootparam" or see the documentation of your boot
794 loader (lilo or loadlin) about how to pass options to the kernel at
795 boot time.) This means that it is a good idea to say Y here if you
796 intend to use this kernel on different machines.
797
798 More information about the internals of the Linux math coprocessor
799 emulation can be found in <file:arch/x86/math-emu/README>.
800
801 If you are not sure, say Y; apart from resulting in a 66 KB bigger
802 kernel, it won't hurt.
803
804config MTRR
805 bool "MTRR (Memory Type Range Register) support"
806 ---help---
807 On Intel P6 family processors (Pentium Pro, Pentium II and later)
808 the Memory Type Range Registers (MTRRs) may be used to control
809 processor access to memory ranges. This is most useful if you have
810 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
811 allows bus write transfers to be combined into a larger transfer
812 before bursting over the PCI/AGP bus. This can increase performance
813 of image write operations 2.5 times or more. Saying Y here creates a
814 /proc/mtrr file which may be used to manipulate your processor's
815 MTRRs. Typically the X server should use this.
816
817 This code has a reasonably generic interface so that similar
818 control registers on other processors can be easily supported
819 as well:
820
821 The Cyrix 6x86, 6x86MX and M II processors have Address Range
822 Registers (ARRs) which provide a similar functionality to MTRRs. For
823 these, the ARRs are used to emulate the MTRRs.
824 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
825 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
826 write-combining. All of these processors are supported by this code
827 and it makes sense to say Y here if you have one of them.
828
829 Saying Y here also fixes a problem with buggy SMP BIOSes which only
830 set the MTRRs for the boot CPU and not for the secondary CPUs. This
831 can lead to all sorts of problems, so it's good to say Y here.
832
833 You can safely say Y even if your machine doesn't have MTRRs, you'll
834 just add about 9 KB to your kernel.
835
836 See <file:Documentation/mtrr.txt> for more information.
837
838config EFI
839 bool "Boot from EFI support"
840 depends on X86_32 && ACPI
841 default n
842 ---help---
843 This enables the kernel to boot on EFI platforms using
844 system configuration information passed to it from the firmware.
845 This also enables the kernel to use any EFI runtime services that are
846 available (such as the EFI variable services).
847
848 This option is only useful on systems that have EFI firmware
849 and will result in a kernel image that is ~8k larger. In addition,
850 you must use the latest ELILO loader available at
851 <http://elilo.sourceforge.net> in order to take advantage of
852 kernel initialization using EFI information (neither GRUB nor LILO know
853 anything about EFI). However, even with this option, the resultant
854 kernel should continue to boot on existing non-EFI platforms.
855
856config IRQBALANCE
857 bool "Enable kernel irq balancing"
858 depends on X86_32 && SMP && X86_IO_APIC
859 default y
860 help
861 The default yes will allow the kernel to do irq load balancing.
862 Saying no will keep the kernel from doing irq load balancing.
863
864# turning this on wastes a bunch of space.
865# Summit needs it only when NUMA is on
866config BOOT_IOREMAP
867 bool
868 depends on X86_32 && (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
869 default y
870
871config SECCOMP
872 bool "Enable seccomp to safely compute untrusted bytecode"
873 depends on PROC_FS
874 default y
875 help
876 This kernel feature is useful for number crunching applications
877 that may need to compute untrusted bytecode during their
878 execution. By using pipes or other transports made available to
879 the process as file descriptors supporting the read/write
880 syscalls, it's possible to isolate those applications in
881 their own address space using seccomp. Once seccomp is
882 enabled via /proc/<pid>/seccomp, it cannot be disabled
883 and the task is only allowed to execute a few safe syscalls
884 defined by each seccomp mode.
885
886 If unsure, say Y. Only embedded should say N here.
887
888config CC_STACKPROTECTOR
889 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
890 depends on X86_64 && EXPERIMENTAL
891 help
892 This option turns on the -fstack-protector GCC feature. This
893 feature puts, at the beginning of critical functions, a canary
894 value on the stack just before the return address, and validates
895 the value just before actually returning. Stack based buffer
896 overflows (that need to overwrite this return address) now also
897 overwrite the canary, which gets detected and the attack is then
898 neutralized via a kernel panic.
899
900 This feature requires gcc version 4.2 or above, or a distribution
901 gcc with the feature backported. Older versions are automatically
902 detected and for those versions, this configuration option is ignored.
903
904config CC_STACKPROTECTOR_ALL
905 bool "Use stack-protector for all functions"
906 depends on CC_STACKPROTECTOR
907 help
908 Normally, GCC only inserts the canary value protection for
909 functions that use large-ish on-stack buffers. By enabling
910 this option, GCC will be asked to do this for ALL functions.
911
912source kernel/Kconfig.hz
913
914config KEXEC
915 bool "kexec system call"
916 help
917 kexec is a system call that implements the ability to shutdown your
918 current kernel, and to start another kernel. It is like a reboot
919 but it is independent of the system firmware. And like a reboot
920 you can start any kernel with it, not just Linux.
921
922 The name comes from the similarity to the exec system call.
923
924 It is an ongoing process to be certain the hardware in a machine
925 is properly shutdown, so do not be surprised if this code does not
926 initially work for you. It may help to enable device hotplugging
927 support. As of this writing the exact hardware interface is
928 strongly in flux, so no good recommendation can be made.
929
930config CRASH_DUMP
931 bool "kernel crash dumps (EXPERIMENTAL)"
932 depends on EXPERIMENTAL
933 depends on X86_64 || (X86_32 && HIGHMEM)
934 help
935 Generate crash dump after being started by kexec.
936 This should be normally only set in special crash dump kernels
937 which are loaded in the main kernel with kexec-tools into
938 a specially reserved region and then later executed after
939 a crash by kdump/kexec. The crash dump kernel must be compiled
940 to a memory address not used by the main kernel or BIOS using
941 PHYSICAL_START, or it must be built as a relocatable image
942 (CONFIG_RELOCATABLE=y).
943 For more details see Documentation/kdump/kdump.txt
944
945config PHYSICAL_START
946 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
947 default "0x1000000" if X86_NUMAQ
948 default "0x200000" if X86_64
949 default "0x100000"
950 help
951 This gives the physical address where the kernel is loaded.
952
953 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
954 bzImage will decompress itself to above physical address and
955 run from there. Otherwise, bzImage will run from the address where
956 it has been loaded by the boot loader and will ignore above physical
957 address.
958
959 In normal kdump cases one does not have to set/change this option
960 as now bzImage can be compiled as a completely relocatable image
961 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
962 address. This option is mainly useful for the folks who don't want
963 to use a bzImage for capturing the crash dump and want to use a
964 vmlinux instead. vmlinux is not relocatable hence a kernel needs
965 to be specifically compiled to run from a specific memory area
966 (normally a reserved region) and this option comes handy.
967
968 So if you are using bzImage for capturing the crash dump, leave
969 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
970 Otherwise if you plan to use vmlinux for capturing the crash dump
971 change this value to start of the reserved region (Typically 16MB
972 0x1000000). In other words, it can be set based on the "X" value as
973 specified in the "crashkernel=YM@XM" command line boot parameter
974 passed to the panic-ed kernel. Typically this parameter is set as
975 crashkernel=64M@16M. Please take a look at
976 Documentation/kdump/kdump.txt for more details about crash dumps.
977
978 Usage of bzImage for capturing the crash dump is recommended as
979 one does not have to build two kernels. Same kernel can be used
980 as production kernel and capture kernel. Above option should have
981 gone away after relocatable bzImage support is introduced. But it
982 is present because there are users out there who continue to use
983 vmlinux for dump capture. This option should go away down the
984 line.
985
986 Don't change this unless you know what you are doing.
987
988config RELOCATABLE
989 bool "Build a relocatable kernel (EXPERIMENTAL)"
990 depends on EXPERIMENTAL
991 help
992 This builds a kernel image that retains relocation information
993 so it can be loaded someplace besides the default 1MB.
994 The relocations tend to make the kernel binary about 10% larger,
995 but are discarded at runtime.
996
997 One use is for the kexec on panic case where the recovery kernel
998 must live at a different physical address than the primary
999 kernel.
1000
1001 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1002 it has been loaded at and the compile time physical address
1003 (CONFIG_PHYSICAL_START) is ignored.
1004
1005config PHYSICAL_ALIGN
1006 hex
1007 prompt "Alignment value to which kernel should be aligned" if X86_32
1008 default "0x100000" if X86_32
1009 default "0x200000" if X86_64
1010 range 0x2000 0x400000
1011 help
1012 This value puts the alignment restrictions on physical address
1013 where kernel is loaded and run from. Kernel is compiled for an
1014 address which meets above alignment restriction.
1015
1016 If bootloader loads the kernel at a non-aligned address and
1017 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1018 address aligned to above value and run from there.
1019
1020 If bootloader loads the kernel at a non-aligned address and
1021 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1022 load address and decompress itself to the address it has been
1023 compiled for and run from there. The address for which kernel is
1024 compiled already meets above alignment restrictions. Hence the
1025 end result is that kernel runs from a physical address meeting
1026 above alignment restrictions.
1027
1028 Don't change this unless you know what you are doing.
1029
1030config HOTPLUG_CPU
1031 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1032 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1033 ---help---
1034 Say Y here to experiment with turning CPUs off and on, and to
1035 enable suspend on SMP systems. CPUs can be controlled through
1036 /sys/devices/system/cpu.
1037 Say N if you want to disable CPU hotplug and don't need to
1038 suspend.
1039
1040config COMPAT_VDSO
1041 bool "Compat VDSO support"
1042 default y
1043 depends on X86_32
1044 help
1045 Map the VDSO to the predictable old-style address too.
1046 ---help---
1047 Say N here if you are running a sufficiently recent glibc
1048 version (2.3.3 or later), to remove the high-mapped
1049 VDSO mapping and to exclusively use the randomized VDSO.
1050
1051 If unsure, say Y.
1052
1053endmenu
1054
1055config ARCH_ENABLE_MEMORY_HOTPLUG
1056 def_bool y
1057 depends on X86_64 || (X86_32 && HIGHMEM)
1058
1059config MEMORY_HOTPLUG_RESERVE
1060 def_bool X86_64
1061 depends on (MEMORY_HOTPLUG && DISCONTIGMEM)
1062
1063config HAVE_ARCH_EARLY_PFN_TO_NID
1064 def_bool X86_64
1065 depends on NUMA
1066
1067config OUT_OF_LINE_PFN_TO_PAGE
1068 def_bool X86_64
1069 depends on DISCONTIGMEM
1070 17
1071source "arch/x86/Kconfig" 18source "arch/x86/Kconfig"
diff --git a/arch/x86/Kconfig.x86_64 b/arch/x86/Kconfig.x86_64
index e441062472a8..b262aaec67cc 100644
--- a/arch/x86/Kconfig.x86_64
+++ b/arch/x86/Kconfig.x86_64
@@ -17,494 +17,4 @@ config X86_64
17 classical 32-bit x86 architecture. For details see 17 classical 32-bit x86 architecture. For details see
18 <http://www.x86-64.org/>. 18 <http://www.x86-64.org/>.
19 19
20source "init/Kconfig"
21
22
23menu "Processor type and features"
24
25source "kernel/time/Kconfig"
26
27choice
28 prompt "Subarchitecture Type"
29 default X86_PC
30
31config X86_PC
32 bool "PC-compatible"
33 help
34 Choose this option if your computer is a standard PC or compatible.
35
36config X86_VSMP
37 bool "Support for ScaleMP vSMP"
38 depends on X86_64 && PCI
39 help
40 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
41 supposed to run on these EM64T-based machines. Only choose this option
42 if you have one of these machines.
43
44endchoice
45
46source "arch/x86/Kconfig.cpu"
47
48config MICROCODE
49 tristate "/dev/cpu/microcode - Intel CPU microcode support"
50 select FW_LOADER
51 ---help---
52 If you say Y here the 'File systems' section, you will be
53 able to update the microcode on Intel processors. You will
54 obviously need the actual microcode binary data itself which is
55 not shipped with the Linux kernel.
56
57 For latest news and information on obtaining all the required
58 ingredients for this driver, check:
59 <http://www.urbanmyth.org/microcode/>.
60
61 To compile this driver as a module, choose M here: the
62 module will be called microcode.
63 If you use modprobe or kmod you may also want to add the line
64 'alias char-major-10-184 microcode' to your /etc/modules.conf file.
65
66config MICROCODE_OLD_INTERFACE
67 bool
68 depends on MICROCODE
69 default y
70
71config X86_MSR
72 tristate "/dev/cpu/*/msr - Model-specific register support"
73 help
74 This device gives privileged processes access to the x86
75 Model-Specific Registers (MSRs). It is a character device with
76 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
77 MSR accesses are directed to a specific CPU on multi-processor
78 systems.
79
80config X86_CPUID
81 tristate "/dev/cpu/*/cpuid - CPU information support"
82 help
83 This device gives processes access to the x86 CPUID instruction to
84 be executed on a specific processor. It is a character device
85 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
86 /dev/cpu/31/cpuid.
87
88config MATH_EMULATION
89 bool
90
91config MCA
92 bool
93
94config EISA
95 bool
96
97config X86_IO_APIC
98 bool
99 default y
100
101config X86_LOCAL_APIC
102 bool
103 default y
104
105config MTRR
106 bool "MTRR (Memory Type Range Register) support"
107 ---help---
108 On Intel P6 family processors (Pentium Pro, Pentium II and later)
109 the Memory Type Range Registers (MTRRs) may be used to control
110 processor access to memory ranges. This is most useful if you have
111 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
112 allows bus write transfers to be combined into a larger transfer
113 before bursting over the PCI/AGP bus. This can increase performance
114 of image write operations 2.5 times or more. Saying Y here creates a
115 /proc/mtrr file which may be used to manipulate your processor's
116 MTRRs. Typically the X server should use this.
117
118 This code has a reasonably generic interface so that similar
119 control registers on other processors can be easily supported
120 as well.
121
122 Saying Y here also fixes a problem with buggy SMP BIOSes which only
123 set the MTRRs for the boot CPU and not for the secondary CPUs. This
124 can lead to all sorts of problems, so it's good to say Y here.
125
126 Just say Y here, all x86-64 machines support MTRRs.
127
128 See <file:Documentation/mtrr.txt> for more information.
129
130config SMP
131 bool "Symmetric multi-processing support"
132 ---help---
133 This enables support for systems with more than one CPU. If you have
134 a system with only one CPU, like most personal computers, say N. If
135 you have a system with more than one CPU, say Y.
136
137 If you say N here, the kernel will run on single and multiprocessor
138 machines, but will use only one CPU of a multiprocessor machine. If
139 you say Y here, the kernel will run on many, but not all,
140 singleprocessor machines. On a singleprocessor machine, the kernel
141 will run faster if you say N here.
142
143 If you don't know what to do here, say N.
144
145config SCHED_SMT
146 bool "SMT (Hyperthreading) scheduler support"
147 depends on SMP
148 default n
149 help
150 SMT scheduler support improves the CPU scheduler's decision making
151 when dealing with Intel Pentium 4 chips with HyperThreading at a
152 cost of slightly increased overhead in some places. If unsure say
153 N here.
154
155config SCHED_MC
156 bool "Multi-core scheduler support"
157 depends on SMP
158 default y
159 help
160 Multi-core scheduler support improves the CPU scheduler's decision
161 making when dealing with multi-core CPU chips at a cost of slightly
162 increased overhead in some places. If unsure say N here.
163
164source "kernel/Kconfig.preempt"
165
166config NUMA
167 bool "Non Uniform Memory Access (NUMA) Support"
168 depends on SMP
169 help
170 Enable NUMA (Non Uniform Memory Access) support. The kernel
171 will try to allocate memory used by a CPU on the local memory
172 controller of the CPU and add some more NUMA awareness to the kernel.
173 This code is recommended on all multiprocessor Opteron systems.
174 If the system is EM64T, you should say N unless your system is EM64T
175 NUMA.
176
177config K8_NUMA
178 bool "Old style AMD Opteron NUMA detection"
179 depends on X86_64 && NUMA && PCI
180 default y
181 help
182 Enable K8 NUMA node topology detection. You should say Y here if
183 you have a multi processor AMD K8 system. This uses an old
184 method to read the NUMA configuration directly from the builtin
185 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
186 instead, which also takes priority if both are compiled in.
187
188config NODES_SHIFT
189 int
190 default "6" if X86_64
191 depends on NEED_MULTIPLE_NODES
192
193# Dummy CONFIG option to select ACPI_NUMA from drivers/acpi/Kconfig.
194
195config X86_64_ACPI_NUMA
196 bool "ACPI NUMA detection"
197 depends on X86_64 && NUMA
198 select ACPI
199 select PCI
200 select ACPI_NUMA
201 default y
202 help
203 Enable ACPI SRAT based node topology detection.
204
205config NUMA_EMU
206 bool "NUMA emulation"
207 depends on X86_64 && NUMA
208 help
209 Enable NUMA emulation. A flat machine will be split
210 into virtual nodes when booted with "numa=fake=N", where N is the
211 number of nodes. This is only useful for debugging.
212
213config ARCH_DISCONTIGMEM_ENABLE
214 bool
215 depends on NUMA
216 default y
217
218config ARCH_DISCONTIGMEM_DEFAULT
219 def_bool y
220 depends on NUMA
221
222config ARCH_SPARSEMEM_ENABLE
223 def_bool y
224 depends on (NUMA || EXPERIMENTAL)
225 select SPARSEMEM_VMEMMAP_ENABLE
226
227config ARCH_MEMORY_PROBE
228 def_bool X86_64
229 depends on MEMORY_HOTPLUG
230
231config ARCH_FLATMEM_ENABLE
232 def_bool y
233 depends on !NUMA
234
235source "mm/Kconfig"
236
237config MEMORY_HOTPLUG_RESERVE
238 def_bool X86_64
239 depends on (MEMORY_HOTPLUG && DISCONTIGMEM)
240
241config HAVE_ARCH_EARLY_PFN_TO_NID
242 def_bool X86_64
243 depends on NUMA
244
245config OUT_OF_LINE_PFN_TO_PAGE
246 def_bool X86_64
247 depends on DISCONTIGMEM
248
249config NR_CPUS
250 int "Maximum number of CPUs (2-255)"
251 range 2 255
252 depends on SMP
253 default "8"
254 help
255 This allows you to specify the maximum number of CPUs which this
256 kernel will support. Current maximum is 255 CPUs due to
257 APIC addressing limits. Less depending on the hardware.
258
259 This is purely to save memory - each supported CPU requires
260 memory in the static kernel configuration.
261
262config PHYSICAL_ALIGN
263 hex
264 default "0x200000" if X86_64
265
266config HOTPLUG_CPU
267 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
268 depends on SMP && HOTPLUG && EXPERIMENTAL
269 help
270 Say Y here to experiment with turning CPUs off and on. CPUs
271 can be controlled through /sys/devices/system/cpu/cpu#.
272 This is also required for suspend/hibernation on SMP systems.
273
274 Say N if you want to disable CPU hotplug and don't need to
275 suspend.
276
277config ARCH_ENABLE_MEMORY_HOTPLUG
278 def_bool y
279
280config HPET_TIMER
281 bool
282 default y
283 help
284 Use the IA-PC HPET (High Precision Event Timer) to manage
285 time in preference to the PIT and RTC, if a HPET is
286 present. The HPET provides a stable time base on SMP
287 systems, unlike the TSC, but it is more expensive to access,
288 as it is off-chip. You can find the HPET spec at
289 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
290
291config HPET_EMULATE_RTC
292 bool
293 depends on HPET_TIMER && RTC=y
294 default y
295
296# Mark as embedded because too many people got it wrong.
297# The code disables itself when not needed.
298config GART_IOMMU
299 bool "GART IOMMU support" if EMBEDDED
300 default y
301 select SWIOTLB
302 select AGP
303 depends on X86_64 && PCI
304 help
305 Support for full DMA access of devices with 32bit memory access only
306 on systems with more than 3GB. This is usually needed for USB,
307 sound, many IDE/SATA chipsets and some other devices.
308 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
309 based hardware IOMMU and a software bounce buffer based IOMMU used
310 on Intel systems and as fallback.
311 The code is only active when needed (enough memory and limited
312 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
313 too.
314
315config CALGARY_IOMMU
316 bool "IBM Calgary IOMMU support"
317 select SWIOTLB
318 depends on X86_64 && PCI && EXPERIMENTAL
319 help
320 Support for hardware IOMMUs in IBM's xSeries x366 and x460
321 systems. Needed to run systems with more than 3GB of memory
322 properly with 32-bit PCI devices that do not support DAC
323 (Double Address Cycle). Calgary also supports bus level
324 isolation, where all DMAs pass through the IOMMU. This
325 prevents them from going anywhere except their intended
326 destination. This catches hard-to-find kernel bugs and
327 mis-behaving drivers and devices that do not use the DMA-API
328 properly to set up their DMA buffers. The IOMMU can be
329 turned off at boot time with the iommu=off parameter.
330 Normally the kernel will make the right choice by itself.
331 If unsure, say Y.
332
333config CALGARY_IOMMU_ENABLED_BY_DEFAULT
334 bool "Should Calgary be enabled by default?"
335 default y
336 depends on CALGARY_IOMMU
337 help
338 Should Calgary be enabled by default? if you choose 'y', Calgary
339 will be used (if it exists). If you choose 'n', Calgary will not be
340 used even if it exists. If you choose 'n' and would like to use
341 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
342 If unsure, say Y.
343
344# need this always selected by IOMMU for the VIA workaround
345config SWIOTLB
346 bool
347 help
348 Support for software bounce buffers used on x86-64 systems
349 which don't have a hardware IOMMU (e.g. the current generation
350 of Intel's x86-64 CPUs). Using this PCI devices which can only
351 access 32-bits of memory can be used on systems with more than
352 3 GB of memory. If unsure, say Y.
353
354config X86_MCE
355 bool "Machine check support" if EMBEDDED
356 default y
357 help
358 Include a machine check error handler to report hardware errors.
359 This version will require the mcelog utility to decode some
360 machine check error logs. See
361 ftp://ftp.x86-64.org/pub/linux/tools/mcelog
362
363config X86_MCE_INTEL
364 bool "Intel MCE features"
365 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
366 default y
367 help
368 Additional support for intel specific MCE features such as
369 the thermal monitor.
370
371config X86_MCE_AMD
372 bool "AMD MCE features"
373 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
374 default y
375 help
376 Additional support for AMD specific MCE features such as
377 the DRAM Error Threshold.
378
379config KEXEC
380 bool "kexec system call"
381 help
382 kexec is a system call that implements the ability to shutdown your
383 current kernel, and to start another kernel. It is like a reboot
384 but it is independent of the system firmware. And like a reboot
385 you can start any kernel with it, not just Linux.
386
387 The name comes from the similarity to the exec system call.
388
389 It is an ongoing process to be certain the hardware in a machine
390 is properly shutdown, so do not be surprised if this code does not
391 initially work for you. It may help to enable device hotplugging
392 support. As of this writing the exact hardware interface is
393 strongly in flux, so no good recommendation can be made.
394
395config CRASH_DUMP
396 bool "kernel crash dumps (EXPERIMENTAL)"
397 depends on EXPERIMENTAL
398 help
399 Generate crash dump after being started by kexec.
400 This should be normally only set in special crash dump kernels
401 which are loaded in the main kernel with kexec-tools into
402 a specially reserved region and then later executed after
403 a crash by kdump/kexec. The crash dump kernel must be compiled
404 to a memory address not used by the main kernel or BIOS using
405 PHYSICAL_START, or it must be built as a relocatable image
406 (CONFIG_RELOCATABLE=y).
407 For more details see Documentation/kdump/kdump.txt
408
409config RELOCATABLE
410 bool "Build a relocatable kernel (EXPERIMENTAL)"
411 depends on EXPERIMENTAL
412 help
413 Builds a relocatable kernel. This enables loading and running
414 a kernel binary from a different physical address than it has
415 been compiled for.
416
417 One use is for the kexec on panic case where the recovery kernel
418 must live at a different physical address than the primary
419 kernel.
420
421 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
422 it has been loaded at and the compile time physical address
423 (CONFIG_PHYSICAL_START) is ignored.
424
425config PHYSICAL_START
426 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
427 default "0x200000"
428 help
429 This gives the physical address where the kernel is loaded. It
430 should be aligned to 2MB boundary.
431
432 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
433 bzImage will decompress itself to above physical address and
434 run from there. Otherwise, bzImage will run from the address where
435 it has been loaded by the boot loader and will ignore above physical
436 address.
437
438 In normal kdump cases one does not have to set/change this option
439 as now bzImage can be compiled as a completely relocatable image
440 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
441 address. This option is mainly useful for the folks who don't want
442 to use a bzImage for capturing the crash dump and want to use a
443 vmlinux instead.
444
445 So if you are using bzImage for capturing the crash dump, leave
446 the value here unchanged to 0x200000 and set CONFIG_RELOCATABLE=y.
447 Otherwise if you plan to use vmlinux for capturing the crash dump
448 change this value to start of the reserved region (Typically 16MB
449 0x1000000). In other words, it can be set based on the "X" value as
450 specified in the "crashkernel=YM@XM" command line boot parameter
451 passed to the panic-ed kernel. Typically this parameter is set as
452 crashkernel=64M@16M. Please take a look at
453 Documentation/kdump/kdump.txt for more details about crash dumps.
454
455 Usage of bzImage for capturing the crash dump is advantageous as
456 one does not have to build two kernels. Same kernel can be used
457 as production kernel and capture kernel.
458
459 Don't change this unless you know what you are doing.
460
461config SECCOMP
462 bool "Enable seccomp to safely compute untrusted bytecode"
463 depends on PROC_FS
464 default y
465 help
466 This kernel feature is useful for number crunching applications
467 that may need to compute untrusted bytecode during their
468 execution. By using pipes or other transports made available to
469 the process as file descriptors supporting the read/write
470 syscalls, it's possible to isolate those applications in
471 their own address space using seccomp. Once seccomp is
472 enabled via /proc/<pid>/seccomp, it cannot be disabled
473 and the task is only allowed to execute a few safe syscalls
474 defined by each seccomp mode.
475
476 If unsure, say Y. Only embedded should say N here.
477
478config CC_STACKPROTECTOR
479 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
480 depends on X86_64 && EXPERIMENTAL
481 help
482 This option turns on the -fstack-protector GCC feature. This
483 feature puts, at the beginning of critical functions, a canary
484 value on the stack just before the return address, and validates
485 the value just before actually returning. Stack based buffer
486 overflows (that need to overwrite this return address) now also
487 overwrite the canary, which gets detected and the attack is then
488 neutralized via a kernel panic.
489
490 This feature requires gcc version 4.2 or above, or a distribution
491 gcc with the feature backported. Older versions are automatically
492 detected and for those versions, this configuration option is ignored.
493
494config CC_STACKPROTECTOR_ALL
495 bool "Use stack-protector for all functions"
496 depends on CC_STACKPROTECTOR
497 help
498 Normally, GCC only inserts the canary value protection for
499 functions that use large-ish on-stack buffers. By enabling
500 this option, GCC will be asked to do this for ALL functions.
501
502source kernel/Kconfig.hz
503
504config K8_NB
505 def_bool X86_64
506 depends on AGP_AMD64 || GART_IOMMU || (PCI && NUMA)
507
508endmenu
509
510source "arch/x86/Kconfig" 20source "arch/x86/Kconfig"