xref: /linux/arch/loongarch/Kconfig (revision 5f346a6e5970229c19c059e8fa62c3dbdde56e7b)
1# SPDX-License-Identifier: GPL-2.0
2config LOONGARCH
3	bool
4	default y
5	select ACPI
6	select ACPI_GENERIC_GSI if ACPI
7	select ACPI_MCFG if ACPI
8	select ACPI_PPTT if ACPI
9	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
10	select ARCH_BINFMT_ELF_STATE
11	select ARCH_DISABLE_KASAN_INLINE
12	select ARCH_ENABLE_MEMORY_HOTPLUG
13	select ARCH_ENABLE_MEMORY_HOTREMOVE
14	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
15	select ARCH_HAS_CPU_FINALIZE_INIT
16	select ARCH_HAS_FORTIFY_SOURCE
17	select ARCH_HAS_KCOV
18	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
19	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
20	select ARCH_HAS_PTE_SPECIAL
21	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
22	select ARCH_INLINE_READ_LOCK if !PREEMPTION
23	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
24	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
25	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
26	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
27	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
28	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
29	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
30	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
31	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
32	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
33	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
34	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
35	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
36	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
37	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
38	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
39	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
40	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
41	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
42	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
43	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
44	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
45	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
46	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
47	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
48	select ARCH_KEEP_MEMBLOCK
49	select ARCH_MIGHT_HAVE_PC_PARPORT
50	select ARCH_MIGHT_HAVE_PC_SERIO
51	select ARCH_SPARSEMEM_ENABLE
52	select ARCH_STACKWALK
53	select ARCH_SUPPORTS_ACPI
54	select ARCH_SUPPORTS_ATOMIC_RMW
55	select ARCH_SUPPORTS_HUGETLBFS
56	select ARCH_SUPPORTS_LTO_CLANG
57	select ARCH_SUPPORTS_LTO_CLANG_THIN
58	select ARCH_SUPPORTS_NUMA_BALANCING
59	select ARCH_USE_BUILTIN_BSWAP
60	select ARCH_USE_CMPXCHG_LOCKREF
61	select ARCH_USE_QUEUED_RWLOCKS
62	select ARCH_USE_QUEUED_SPINLOCKS
63	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
64	select ARCH_WANT_LD_ORPHAN_WARN
65	select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP
66	select ARCH_WANTS_NO_INSTR
67	select BUILDTIME_TABLE_SORT
68	select COMMON_CLK
69	select CPU_PM
70	select EFI
71	select GENERIC_CLOCKEVENTS
72	select GENERIC_CMOS_UPDATE
73	select GENERIC_CPU_AUTOPROBE
74	select GENERIC_ENTRY
75	select GENERIC_GETTIMEOFDAY
76	select GENERIC_IOREMAP if !ARCH_IOREMAP
77	select GENERIC_IRQ_MULTI_HANDLER
78	select GENERIC_IRQ_PROBE
79	select GENERIC_IRQ_SHOW
80	select GENERIC_LIB_ASHLDI3
81	select GENERIC_LIB_ASHRDI3
82	select GENERIC_LIB_CMPDI2
83	select GENERIC_LIB_LSHRDI3
84	select GENERIC_LIB_UCMPDI2
85	select GENERIC_LIB_DEVMEM_IS_ALLOWED
86	select GENERIC_PCI_IOMAP
87	select GENERIC_SCHED_CLOCK
88	select GENERIC_SMP_IDLE_THREAD
89	select GENERIC_TIME_VSYSCALL
90	select GENERIC_VDSO_TIME_NS
91	select GPIOLIB
92	select HAS_IOPORT
93	select HAVE_ARCH_AUDITSYSCALL
94	select HAVE_ARCH_JUMP_LABEL
95	select HAVE_ARCH_JUMP_LABEL_RELATIVE
96	select HAVE_ARCH_KASAN
97	select HAVE_ARCH_KFENCE
98	select HAVE_ARCH_KGDB if PERF_EVENTS
99	select HAVE_ARCH_MMAP_RND_BITS if MMU
100	select HAVE_ARCH_SECCOMP_FILTER
101	select HAVE_ARCH_TRACEHOOK
102	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
103	select HAVE_ASM_MODVERSIONS
104	select HAVE_CONTEXT_TRACKING_USER
105	select HAVE_C_RECORDMCOUNT
106	select HAVE_DEBUG_KMEMLEAK
107	select HAVE_DEBUG_STACKOVERFLOW
108	select HAVE_DMA_CONTIGUOUS
109	select HAVE_DYNAMIC_FTRACE
110	select HAVE_DYNAMIC_FTRACE_WITH_ARGS
111	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
112	select HAVE_DYNAMIC_FTRACE_WITH_REGS
113	select HAVE_EBPF_JIT
114	select HAVE_EFFICIENT_UNALIGNED_ACCESS if !ARCH_STRICT_ALIGN
115	select HAVE_EXIT_THREAD
116	select HAVE_FAST_GUP
117	select HAVE_FTRACE_MCOUNT_RECORD
118	select HAVE_FUNCTION_ARG_ACCESS_API
119	select HAVE_FUNCTION_ERROR_INJECTION
120	select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
121	select HAVE_FUNCTION_GRAPH_TRACER
122	select HAVE_FUNCTION_TRACER
123	select HAVE_GCC_PLUGINS
124	select HAVE_GENERIC_VDSO
125	select HAVE_HW_BREAKPOINT if PERF_EVENTS
126	select HAVE_IOREMAP_PROT
127	select HAVE_IRQ_EXIT_ON_IRQ_STACK
128	select HAVE_IRQ_TIME_ACCOUNTING
129	select HAVE_KPROBES
130	select HAVE_KPROBES_ON_FTRACE
131	select HAVE_KRETPROBES
132	select HAVE_KVM
133	select HAVE_MOD_ARCH_SPECIFIC
134	select HAVE_NMI
135	select HAVE_PCI
136	select HAVE_PERF_EVENTS
137	select HAVE_PERF_REGS
138	select HAVE_PERF_USER_STACK_DUMP
139	select HAVE_PREEMPT_DYNAMIC_KEY
140	select HAVE_REGS_AND_STACK_ACCESS_API
141	select HAVE_RETHOOK
142	select HAVE_RSEQ
143	select HAVE_RUST
144	select HAVE_SAMPLE_FTRACE_DIRECT
145	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
146	select HAVE_SETUP_PER_CPU_AREA if NUMA
147	select HAVE_STACKPROTECTOR
148	select HAVE_SYSCALL_TRACEPOINTS
149	select HAVE_TIF_NOHZ
150	select HAVE_VIRT_CPU_ACCOUNTING_GEN if !SMP
151	select IRQ_FORCED_THREADING
152	select IRQ_LOONGARCH_CPU
153	select LOCK_MM_AND_FIND_VMA
154	select MMU_GATHER_MERGE_VMAS if MMU
155	select MODULES_USE_ELF_RELA if MODULES
156	select NEED_PER_CPU_EMBED_FIRST_CHUNK
157	select NEED_PER_CPU_PAGE_FIRST_CHUNK
158	select OF
159	select OF_EARLY_FLATTREE
160	select PCI
161	select PCI_DOMAINS_GENERIC
162	select PCI_ECAM if ACPI
163	select PCI_LOONGSON
164	select PCI_MSI_ARCH_FALLBACKS
165	select PCI_QUIRKS
166	select PERF_USE_VMALLOC
167	select RTC_LIB
168	select SMP
169	select SPARSE_IRQ
170	select SYSCTL_ARCH_UNALIGN_ALLOW
171	select SYSCTL_ARCH_UNALIGN_NO_WARN
172	select SYSCTL_EXCEPTION_TRACE
173	select SWIOTLB
174	select TRACE_IRQFLAGS_SUPPORT
175	select USE_PERCPU_NUMA_NODE_ID
176	select USER_STACKTRACE_SUPPORT
177	select ZONE_DMA32
178
179config 32BIT
180	bool
181
182config 64BIT
183	def_bool y
184
185config GENERIC_BUG
186	def_bool y
187	depends on BUG
188
189config GENERIC_BUG_RELATIVE_POINTERS
190	def_bool y
191	depends on GENERIC_BUG
192
193config GENERIC_CALIBRATE_DELAY
194	def_bool y
195
196config GENERIC_CSUM
197	def_bool y
198
199config GENERIC_HWEIGHT
200	def_bool y
201
202config L1_CACHE_SHIFT
203	int
204	default "6"
205
206config LOCKDEP_SUPPORT
207	bool
208	default y
209
210config STACKTRACE_SUPPORT
211	bool
212	default y
213
214# MACH_LOONGSON32 and MACH_LOONGSON64 are deliberately carried over from the
215# MIPS Loongson code, to preserve Loongson-specific code paths in drivers that
216# are shared between architectures, and specifically expecting the symbols.
217config MACH_LOONGSON32
218	def_bool 32BIT
219
220config MACH_LOONGSON64
221	def_bool 64BIT
222
223config FIX_EARLYCON_MEM
224	def_bool y
225
226config PAGE_SIZE_4KB
227	bool
228
229config PAGE_SIZE_16KB
230	bool
231
232config PAGE_SIZE_64KB
233	bool
234
235config PGTABLE_2LEVEL
236	bool
237
238config PGTABLE_3LEVEL
239	bool
240
241config PGTABLE_4LEVEL
242	bool
243
244config PGTABLE_LEVELS
245	int
246	default 2 if PGTABLE_2LEVEL
247	default 3 if PGTABLE_3LEVEL
248	default 4 if PGTABLE_4LEVEL
249
250config SCHED_OMIT_FRAME_POINTER
251	bool
252	default y
253
254config AS_HAS_EXPLICIT_RELOCS
255	def_bool $(as-instr,x:pcalau12i \$t0$(comma)%pc_hi20(x))
256
257config AS_HAS_FCSR_CLASS
258	def_bool $(as-instr,movfcsr2gr \$t0$(comma)\$fcsr0)
259
260config AS_HAS_LSX_EXTENSION
261	def_bool $(as-instr,vld \$vr0$(comma)\$a0$(comma)0)
262
263config AS_HAS_LASX_EXTENSION
264	def_bool $(as-instr,xvld \$xr0$(comma)\$a0$(comma)0)
265
266config AS_HAS_LBT_EXTENSION
267	def_bool $(as-instr,movscr2gr \$a0$(comma)\$scr0)
268
269config AS_HAS_LVZ_EXTENSION
270	def_bool $(as-instr,hvcl 0)
271
272menu "Kernel type and options"
273
274source "kernel/Kconfig.hz"
275
276choice
277	prompt "Page Table Layout"
278	default 16KB_2LEVEL if 32BIT
279	default 16KB_3LEVEL if 64BIT
280	help
281	  Allows choosing the page table layout, which is a combination
282	  of page size and page table levels. The size of virtual memory
283	  address space are determined by the page table layout.
284
285config 4KB_3LEVEL
286	bool "4KB with 3 levels"
287	select PAGE_SIZE_4KB
288	select PGTABLE_3LEVEL
289	help
290	  This option selects 4KB page size with 3 level page tables, which
291	  support a maximum of 39 bits of application virtual memory.
292
293config 4KB_4LEVEL
294	bool "4KB with 4 levels"
295	select PAGE_SIZE_4KB
296	select PGTABLE_4LEVEL
297	help
298	  This option selects 4KB page size with 4 level page tables, which
299	  support a maximum of 48 bits of application virtual memory.
300
301config 16KB_2LEVEL
302	bool "16KB with 2 levels"
303	select PAGE_SIZE_16KB
304	select PGTABLE_2LEVEL
305	help
306	  This option selects 16KB page size with 2 level page tables, which
307	  support a maximum of 36 bits of application virtual memory.
308
309config 16KB_3LEVEL
310	bool "16KB with 3 levels"
311	select PAGE_SIZE_16KB
312	select PGTABLE_3LEVEL
313	help
314	  This option selects 16KB page size with 3 level page tables, which
315	  support a maximum of 47 bits of application virtual memory.
316
317config 64KB_2LEVEL
318	bool "64KB with 2 levels"
319	select PAGE_SIZE_64KB
320	select PGTABLE_2LEVEL
321	help
322	  This option selects 64KB page size with 2 level page tables, which
323	  support a maximum of 42 bits of application virtual memory.
324
325config 64KB_3LEVEL
326	bool "64KB with 3 levels"
327	select PAGE_SIZE_64KB
328	select PGTABLE_3LEVEL
329	help
330	  This option selects 64KB page size with 3 level page tables, which
331	  support a maximum of 55 bits of application virtual memory.
332
333endchoice
334
335config CMDLINE
336	string "Built-in kernel command line"
337	help
338	  For most platforms, the arguments for the kernel's command line
339	  are provided at run-time, during boot. However, there are cases
340	  where either no arguments are being provided or the provided
341	  arguments are insufficient or even invalid.
342
343	  When that occurs, it is possible to define a built-in command
344	  line here and choose how the kernel should use it later on.
345
346choice
347	prompt "Kernel command line type"
348	default CMDLINE_BOOTLOADER
349	help
350	  Choose how the kernel will handle the provided built-in command
351	  line.
352
353config CMDLINE_BOOTLOADER
354	bool "Use bootloader kernel arguments if available"
355	help
356	  Prefer the command-line passed by the boot loader if available.
357	  Use the built-in command line as fallback in case we get nothing
358	  during boot. This is the default behaviour.
359
360config CMDLINE_EXTEND
361	bool "Use built-in to extend bootloader kernel arguments"
362	help
363	  The command-line arguments provided during boot will be
364	  appended to the built-in command line. This is useful in
365	  cases where the provided arguments are insufficient and
366	  you don't want to or cannot modify them.
367
368config CMDLINE_FORCE
369	bool "Always use the built-in kernel command string"
370	help
371	  Always use the built-in command line, even if we get one during
372	  boot. This is useful in case you need to override the provided
373	  command line on systems where you don't have or want control
374	  over it.
375
376endchoice
377
378config BUILTIN_DTB
379	bool "Enable built-in dtb in kernel"
380	depends on OF
381	help
382	  Some existing systems do not provide a canonical device tree to
383	  the kernel at boot time. Let's provide a device tree table in the
384	  kernel, keyed by the dts filename, containing the relevant DTBs.
385
386	  Built-in DTBs are generic enough and can be used as references.
387
388config BUILTIN_DTB_NAME
389	string "Source file for built-in dtb"
390	depends on BUILTIN_DTB
391	help
392	  Base name (without suffix, relative to arch/loongarch/boot/dts/)
393	  for the DTS file that will be used to produce the DTB linked into
394	  the kernel.
395
396config DMI
397	bool "Enable DMI scanning"
398	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
399	default y
400	help
401	  This enables SMBIOS/DMI feature for systems, and scanning of
402	  DMI to identify machine quirks.
403
404config EFI
405	bool "EFI runtime service support"
406	select UCS2_STRING
407	select EFI_RUNTIME_WRAPPERS
408	help
409	  This enables the kernel to use EFI runtime services that are
410	  available (such as the EFI variable services).
411
412config EFI_STUB
413	bool "EFI boot stub support"
414	default y
415	depends on EFI
416	select EFI_GENERIC_STUB
417	help
418	  This kernel feature allows the kernel to be loaded directly by
419	  EFI firmware without the use of a bootloader.
420
421config SCHED_SMT
422	bool "SMT scheduler support"
423	default y
424	help
425	  Improves scheduler's performance when there are multiple
426	  threads in one physical core.
427
428config SMP
429	bool "Multi-Processing support"
430	help
431	  This enables support for systems with more than one CPU. If you have
432	  a system with only one CPU, say N. If you have a system with more
433	  than one CPU, say Y.
434
435	  If you say N here, the kernel will run on uni- and multiprocessor
436	  machines, but will use only one CPU of a multiprocessor machine. If
437	  you say Y here, the kernel will run on many, but not all,
438	  uniprocessor machines. On a uniprocessor machine, the kernel
439	  will run faster if you say N here.
440
441	  See also the SMP-HOWTO available at <http://www.tldp.org/docs.html#howto>.
442
443	  If you don't know what to do here, say N.
444
445config HOTPLUG_CPU
446	bool "Support for hot-pluggable CPUs"
447	depends on SMP
448	select GENERIC_IRQ_MIGRATION
449	help
450	  Say Y here to allow turning CPUs off and on. CPUs can be
451	  controlled through /sys/devices/system/cpu.
452	  (Note: power management support will enable this option
453	    automatically on SMP systems. )
454	  Say N if you want to disable CPU hotplug.
455
456config NR_CPUS
457	int "Maximum number of CPUs (2-256)"
458	range 2 256
459	depends on SMP
460	default "64"
461	help
462	  This allows you to specify the maximum number of CPUs which this
463	  kernel will support.
464
465config NUMA
466	bool "NUMA Support"
467	select SMP
468	select ACPI_NUMA if ACPI
469	help
470	  Say Y to compile the kernel with NUMA (Non-Uniform Memory Access)
471	  support.  This option improves performance on systems with more
472	  than one NUMA node; on single node systems it is generally better
473	  to leave it disabled.
474
475config NODES_SHIFT
476	int
477	default "6"
478	depends on NUMA
479
480config ARCH_FORCE_MAX_ORDER
481	int "Maximum zone order"
482	default "13" if PAGE_SIZE_64KB
483	default "11" if PAGE_SIZE_16KB
484	default "10"
485	help
486	  The kernel memory allocator divides physically contiguous memory
487	  blocks into "zones", where each zone is a power of two number of
488	  pages.  This option selects the largest power of two that the kernel
489	  keeps in the memory allocator.  If you need to allocate very large
490	  blocks of physically contiguous memory, then you may need to
491	  increase this value.
492
493	  The page size is not necessarily 4KB.  Keep this in mind
494	  when choosing a value for this option.
495
496config ARCH_IOREMAP
497	bool "Enable LoongArch DMW-based ioremap()"
498	help
499	  We use generic TLB-based ioremap() by default since it has page
500	  protection support. However, you can enable LoongArch DMW-based
501	  ioremap() for better performance.
502
503config ARCH_WRITECOMBINE
504	bool "Enable WriteCombine (WUC) for ioremap()"
505	help
506	  LoongArch maintains cache coherency in hardware, but when paired
507	  with LS7A chipsets the WUC attribute (Weak-ordered UnCached, which
508	  is similar to WriteCombine) is out of the scope of cache coherency
509	  machanism for PCIe devices (this is a PCIe protocol violation, which
510	  may be fixed in newer chipsets).
511
512	  This means WUC can only used for write-only memory regions now, so
513	  this option is disabled by default, making WUC silently fallback to
514	  SUC for ioremap(). You can enable this option if the kernel is ensured
515	  to run on hardware without this bug.
516
517	  You can override this setting via writecombine=on/off boot parameter.
518
519config ARCH_STRICT_ALIGN
520	bool "Enable -mstrict-align to prevent unaligned accesses" if EXPERT
521	default y
522	help
523	  Not all LoongArch cores support h/w unaligned access, we can use
524	  -mstrict-align build parameter to prevent unaligned accesses.
525
526	  CPUs with h/w unaligned access support:
527	  Loongson-2K2000/2K3000/3A5000/3C5000/3D5000.
528
529	  CPUs without h/w unaligned access support:
530	  Loongson-2K500/2K1000.
531
532	  This option is enabled by default to make the kernel be able to run
533	  on all LoongArch systems. But you can disable it manually if you want
534	  to run kernel only on systems with h/w unaligned access support in
535	  order to optimise for performance.
536
537config CPU_HAS_FPU
538	bool
539	default y
540
541config CPU_HAS_LSX
542	bool "Support for the Loongson SIMD Extension"
543	depends on AS_HAS_LSX_EXTENSION
544	help
545	  Loongson SIMD Extension (LSX) introduces 128 bit wide vector registers
546	  and a set of SIMD instructions to operate on them. When this option
547	  is enabled the kernel will support allocating & switching LSX
548	  vector register contexts. If you know that your kernel will only be
549	  running on CPUs which do not support LSX or that your userland will
550	  not be making use of it then you may wish to say N here to reduce
551	  the size & complexity of your kernel.
552
553	  If unsure, say Y.
554
555config CPU_HAS_LASX
556	bool "Support for the Loongson Advanced SIMD Extension"
557	depends on CPU_HAS_LSX
558	depends on AS_HAS_LASX_EXTENSION
559	help
560	  Loongson Advanced SIMD Extension (LASX) introduces 256 bit wide vector
561	  registers and a set of SIMD instructions to operate on them. When this
562	  option is enabled the kernel will support allocating & switching LASX
563	  vector register contexts. If you know that your kernel will only be
564	  running on CPUs which do not support LASX or that your userland will
565	  not be making use of it then you may wish to say N here to reduce
566	  the size & complexity of your kernel.
567
568	  If unsure, say Y.
569
570config CPU_HAS_LBT
571	bool "Support for the Loongson Binary Translation Extension"
572	depends on AS_HAS_LBT_EXTENSION
573	help
574	  Loongson Binary Translation (LBT) introduces 4 scratch registers (SCR0
575	  to SCR3), x86/ARM eflags (eflags) and x87 fpu stack pointer (ftop).
576	  Enabling this option allows the kernel to allocate and switch registers
577	  specific to LBT.
578
579	  If you want to use this feature, such as the Loongson Architecture
580	  Translator (LAT), say Y.
581
582config CPU_HAS_PREFETCH
583	bool
584	default y
585
586config ARCH_SUPPORTS_KEXEC
587	def_bool y
588
589config ARCH_SUPPORTS_CRASH_DUMP
590	def_bool y
591
592config ARCH_SELECTS_CRASH_DUMP
593	def_bool y
594	depends on CRASH_DUMP
595	select RELOCATABLE
596
597config RELOCATABLE
598	bool "Relocatable kernel"
599	help
600	  This builds the kernel as a Position Independent Executable (PIE),
601	  which retains all relocation metadata required, so as to relocate
602	  the kernel binary at runtime to a different virtual address from
603	  its link address.
604
605config RANDOMIZE_BASE
606	bool "Randomize the address of the kernel (KASLR)"
607	depends on RELOCATABLE
608	help
609	   Randomizes the physical and virtual address at which the
610	   kernel image is loaded, as a security feature that
611	   deters exploit attempts relying on knowledge of the location
612	   of kernel internals.
613
614	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET.
615
616	   If unsure, say N.
617
618config RANDOMIZE_BASE_MAX_OFFSET
619	hex "Maximum KASLR offset" if EXPERT
620	depends on RANDOMIZE_BASE
621	range 0x0 0x10000000
622	default "0x01000000"
623	help
624	  When KASLR is active, this provides the maximum offset that will
625	  be applied to the kernel image. It should be set according to the
626	  amount of physical RAM available in the target system.
627
628	  This is limited by the size of the lower address memory, 256MB.
629
630config SECCOMP
631	bool "Enable seccomp to safely compute untrusted bytecode"
632	depends on PROC_FS
633	default y
634	help
635	  This kernel feature is useful for number crunching applications
636	  that may need to compute untrusted bytecode during their
637	  execution. By using pipes or other transports made available to
638	  the process as file descriptors supporting the read/write
639	  syscalls, it's possible to isolate those applications in
640	  their own address space using seccomp. Once seccomp is
641	  enabled via /proc/<pid>/seccomp, it cannot be disabled
642	  and the task is only allowed to execute a few safe syscalls
643	  defined by each seccomp mode.
644
645	  If unsure, say Y. Only embedded should say N here.
646
647endmenu
648
649config ARCH_SELECT_MEMORY_MODEL
650	def_bool y
651
652config ARCH_FLATMEM_ENABLE
653	def_bool y
654	depends on !NUMA
655
656config ARCH_SPARSEMEM_ENABLE
657	def_bool y
658	select SPARSEMEM_VMEMMAP_ENABLE
659	help
660	  Say Y to support efficient handling of sparse physical memory,
661	  for architectures which are either NUMA (Non-Uniform Memory Access)
662	  or have huge holes in the physical address space for other reasons.
663	  See <file:Documentation/mm/numa.rst> for more.
664
665config ARCH_ENABLE_THP_MIGRATION
666	def_bool y
667	depends on TRANSPARENT_HUGEPAGE
668
669config ARCH_MEMORY_PROBE
670	def_bool y
671	depends on MEMORY_HOTPLUG
672
673config MMU
674	bool
675	default y
676
677config ARCH_MMAP_RND_BITS_MIN
678	default 12
679
680config ARCH_MMAP_RND_BITS_MAX
681	default 18
682
683config ARCH_SUPPORTS_UPROBES
684	def_bool y
685
686config KASAN_SHADOW_OFFSET
687	hex
688	default 0x0
689	depends on KASAN
690
691menu "Power management options"
692
693config ARCH_SUSPEND_POSSIBLE
694	def_bool y
695
696config ARCH_HIBERNATION_POSSIBLE
697	def_bool y
698
699source "kernel/power/Kconfig"
700source "drivers/acpi/Kconfig"
701
702endmenu
703
704source "arch/loongarch/kvm/Kconfig"
705