xref: /linux/arch/x86/kernel/setup.c (revision 90d32e92011eaae8e70a9169b4e7acf4ca8f9d3a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright (C) 1995  Linus Torvalds
4  *
5  * This file contains the setup_arch() code, which handles the architecture-dependent
6  * parts of early kernel initialization.
7  */
8 #include <linux/acpi.h>
9 #include <linux/console.h>
10 #include <linux/cpu.h>
11 #include <linux/crash_dump.h>
12 #include <linux/dma-map-ops.h>
13 #include <linux/efi.h>
14 #include <linux/ima.h>
15 #include <linux/init_ohci1394_dma.h>
16 #include <linux/initrd.h>
17 #include <linux/iscsi_ibft.h>
18 #include <linux/memblock.h>
19 #include <linux/panic_notifier.h>
20 #include <linux/pci.h>
21 #include <linux/root_dev.h>
22 #include <linux/hugetlb.h>
23 #include <linux/tboot.h>
24 #include <linux/usb/xhci-dbgp.h>
25 #include <linux/static_call.h>
26 #include <linux/swiotlb.h>
27 #include <linux/random.h>
28 
29 #include <uapi/linux/mount.h>
30 
31 #include <xen/xen.h>
32 
33 #include <asm/apic.h>
34 #include <asm/efi.h>
35 #include <asm/numa.h>
36 #include <asm/bios_ebda.h>
37 #include <asm/bugs.h>
38 #include <asm/cacheinfo.h>
39 #include <asm/coco.h>
40 #include <asm/cpu.h>
41 #include <asm/efi.h>
42 #include <asm/gart.h>
43 #include <asm/hypervisor.h>
44 #include <asm/io_apic.h>
45 #include <asm/kasan.h>
46 #include <asm/kaslr.h>
47 #include <asm/mce.h>
48 #include <asm/memtype.h>
49 #include <asm/mtrr.h>
50 #include <asm/realmode.h>
51 #include <asm/olpc_ofw.h>
52 #include <asm/pci-direct.h>
53 #include <asm/prom.h>
54 #include <asm/proto.h>
55 #include <asm/thermal.h>
56 #include <asm/unwind.h>
57 #include <asm/vsyscall.h>
58 #include <linux/vmalloc.h>
59 
60 /*
61  * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
62  * max_pfn_mapped:     highest directly mapped pfn > 4 GB
63  *
64  * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
65  * represented by pfn_mapped[].
66  */
67 unsigned long max_low_pfn_mapped;
68 unsigned long max_pfn_mapped;
69 
70 #ifdef CONFIG_DMI
71 RESERVE_BRK(dmi_alloc, 65536);
72 #endif
73 
74 
75 unsigned long _brk_start = (unsigned long)__brk_base;
76 unsigned long _brk_end   = (unsigned long)__brk_base;
77 
78 struct boot_params boot_params;
79 
80 /*
81  * These are the four main kernel memory regions, we put them into
82  * the resource tree so that kdump tools and other debugging tools
83  * recover it:
84  */
85 
86 static struct resource rodata_resource = {
87 	.name	= "Kernel rodata",
88 	.start	= 0,
89 	.end	= 0,
90 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
91 };
92 
93 static struct resource data_resource = {
94 	.name	= "Kernel data",
95 	.start	= 0,
96 	.end	= 0,
97 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
98 };
99 
100 static struct resource code_resource = {
101 	.name	= "Kernel code",
102 	.start	= 0,
103 	.end	= 0,
104 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
105 };
106 
107 static struct resource bss_resource = {
108 	.name	= "Kernel bss",
109 	.start	= 0,
110 	.end	= 0,
111 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
112 };
113 
114 
115 #ifdef CONFIG_X86_32
116 /* CPU data as detected by the assembly code in head_32.S */
117 struct cpuinfo_x86 new_cpu_data;
118 
119 struct apm_info apm_info;
120 EXPORT_SYMBOL(apm_info);
121 
122 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
123 	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
124 struct ist_info ist_info;
125 EXPORT_SYMBOL(ist_info);
126 #else
127 struct ist_info ist_info;
128 #endif
129 
130 #endif
131 
132 struct cpuinfo_x86 boot_cpu_data __read_mostly;
133 EXPORT_SYMBOL(boot_cpu_data);
134 
135 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
136 __visible unsigned long mmu_cr4_features __ro_after_init;
137 #else
138 __visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
139 #endif
140 
141 #ifdef CONFIG_IMA
142 static phys_addr_t ima_kexec_buffer_phys;
143 static size_t ima_kexec_buffer_size;
144 #endif
145 
146 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
147 int bootloader_type, bootloader_version;
148 
149 /*
150  * Setup options
151  */
152 struct screen_info screen_info;
153 EXPORT_SYMBOL(screen_info);
154 struct edid_info edid_info;
155 EXPORT_SYMBOL_GPL(edid_info);
156 
157 extern int root_mountflags;
158 
159 unsigned long saved_video_mode;
160 
161 #define RAMDISK_IMAGE_START_MASK	0x07FF
162 #define RAMDISK_PROMPT_FLAG		0x8000
163 #define RAMDISK_LOAD_FLAG		0x4000
164 
165 static char __initdata command_line[COMMAND_LINE_SIZE];
166 #ifdef CONFIG_CMDLINE_BOOL
167 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
168 #endif
169 
170 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
171 struct edd edd;
172 #ifdef CONFIG_EDD_MODULE
173 EXPORT_SYMBOL(edd);
174 #endif
175 /**
176  * copy_edd() - Copy the BIOS EDD information
177  *              from boot_params into a safe place.
178  *
179  */
180 static inline void __init copy_edd(void)
181 {
182      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
183 	    sizeof(edd.mbr_signature));
184      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
185      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
186      edd.edd_info_nr = boot_params.eddbuf_entries;
187 }
188 #else
189 static inline void __init copy_edd(void)
190 {
191 }
192 #endif
193 
194 void * __init extend_brk(size_t size, size_t align)
195 {
196 	size_t mask = align - 1;
197 	void *ret;
198 
199 	BUG_ON(_brk_start == 0);
200 	BUG_ON(align & mask);
201 
202 	_brk_end = (_brk_end + mask) & ~mask;
203 	BUG_ON((char *)(_brk_end + size) > __brk_limit);
204 
205 	ret = (void *)_brk_end;
206 	_brk_end += size;
207 
208 	memset(ret, 0, size);
209 
210 	return ret;
211 }
212 
213 #ifdef CONFIG_X86_32
214 static void __init cleanup_highmap(void)
215 {
216 }
217 #endif
218 
219 static void __init reserve_brk(void)
220 {
221 	if (_brk_end > _brk_start)
222 		memblock_reserve(__pa_symbol(_brk_start),
223 				 _brk_end - _brk_start);
224 
225 	/* Mark brk area as locked down and no longer taking any
226 	   new allocations */
227 	_brk_start = 0;
228 }
229 
230 #ifdef CONFIG_BLK_DEV_INITRD
231 
232 static u64 __init get_ramdisk_image(void)
233 {
234 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
235 
236 	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
237 
238 	if (ramdisk_image == 0)
239 		ramdisk_image = phys_initrd_start;
240 
241 	return ramdisk_image;
242 }
243 static u64 __init get_ramdisk_size(void)
244 {
245 	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
246 
247 	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
248 
249 	if (ramdisk_size == 0)
250 		ramdisk_size = phys_initrd_size;
251 
252 	return ramdisk_size;
253 }
254 
255 static void __init relocate_initrd(void)
256 {
257 	/* Assume only end is not page aligned */
258 	u64 ramdisk_image = get_ramdisk_image();
259 	u64 ramdisk_size  = get_ramdisk_size();
260 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
261 
262 	/* We need to move the initrd down into directly mapped mem */
263 	u64 relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
264 						      PFN_PHYS(max_pfn_mapped));
265 	if (!relocated_ramdisk)
266 		panic("Cannot find place for new RAMDISK of size %lld\n",
267 		      ramdisk_size);
268 
269 	initrd_start = relocated_ramdisk + PAGE_OFFSET;
270 	initrd_end   = initrd_start + ramdisk_size;
271 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
272 	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
273 
274 	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
275 
276 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
277 		" [mem %#010llx-%#010llx]\n",
278 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
279 		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
280 }
281 
282 static void __init early_reserve_initrd(void)
283 {
284 	/* Assume only end is not page aligned */
285 	u64 ramdisk_image = get_ramdisk_image();
286 	u64 ramdisk_size  = get_ramdisk_size();
287 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
288 
289 	if (!boot_params.hdr.type_of_loader ||
290 	    !ramdisk_image || !ramdisk_size)
291 		return;		/* No initrd provided by bootloader */
292 
293 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
294 }
295 
296 static void __init reserve_initrd(void)
297 {
298 	/* Assume only end is not page aligned */
299 	u64 ramdisk_image = get_ramdisk_image();
300 	u64 ramdisk_size  = get_ramdisk_size();
301 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
302 
303 	if (!boot_params.hdr.type_of_loader ||
304 	    !ramdisk_image || !ramdisk_size)
305 		return;		/* No initrd provided by bootloader */
306 
307 	initrd_start = 0;
308 
309 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
310 			ramdisk_end - 1);
311 
312 	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
313 				PFN_DOWN(ramdisk_end))) {
314 		/* All are mapped, easy case */
315 		initrd_start = ramdisk_image + PAGE_OFFSET;
316 		initrd_end = initrd_start + ramdisk_size;
317 		return;
318 	}
319 
320 	relocate_initrd();
321 
322 	memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image);
323 }
324 
325 #else
326 static void __init early_reserve_initrd(void)
327 {
328 }
329 static void __init reserve_initrd(void)
330 {
331 }
332 #endif /* CONFIG_BLK_DEV_INITRD */
333 
334 static void __init add_early_ima_buffer(u64 phys_addr)
335 {
336 #ifdef CONFIG_IMA
337 	struct ima_setup_data *data;
338 
339 	data = early_memremap(phys_addr + sizeof(struct setup_data), sizeof(*data));
340 	if (!data) {
341 		pr_warn("setup: failed to memremap ima_setup_data entry\n");
342 		return;
343 	}
344 
345 	if (data->size) {
346 		memblock_reserve(data->addr, data->size);
347 		ima_kexec_buffer_phys = data->addr;
348 		ima_kexec_buffer_size = data->size;
349 	}
350 
351 	early_memunmap(data, sizeof(*data));
352 #else
353 	pr_warn("Passed IMA kexec data, but CONFIG_IMA not set. Ignoring.\n");
354 #endif
355 }
356 
357 #if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE)
358 int __init ima_free_kexec_buffer(void)
359 {
360 	if (!ima_kexec_buffer_size)
361 		return -ENOENT;
362 
363 	memblock_free_late(ima_kexec_buffer_phys,
364 			   ima_kexec_buffer_size);
365 
366 	ima_kexec_buffer_phys = 0;
367 	ima_kexec_buffer_size = 0;
368 
369 	return 0;
370 }
371 
372 int __init ima_get_kexec_buffer(void **addr, size_t *size)
373 {
374 	if (!ima_kexec_buffer_size)
375 		return -ENOENT;
376 
377 	*addr = __va(ima_kexec_buffer_phys);
378 	*size = ima_kexec_buffer_size;
379 
380 	return 0;
381 }
382 #endif
383 
384 static void __init parse_setup_data(void)
385 {
386 	struct setup_data *data;
387 	u64 pa_data, pa_next;
388 
389 	pa_data = boot_params.hdr.setup_data;
390 	while (pa_data) {
391 		u32 data_len, data_type;
392 
393 		data = early_memremap(pa_data, sizeof(*data));
394 		data_len = data->len + sizeof(struct setup_data);
395 		data_type = data->type;
396 		pa_next = data->next;
397 		early_memunmap(data, sizeof(*data));
398 
399 		switch (data_type) {
400 		case SETUP_E820_EXT:
401 			e820__memory_setup_extended(pa_data, data_len);
402 			break;
403 		case SETUP_DTB:
404 			add_dtb(pa_data);
405 			break;
406 		case SETUP_EFI:
407 			parse_efi_setup(pa_data, data_len);
408 			break;
409 		case SETUP_IMA:
410 			add_early_ima_buffer(pa_data);
411 			break;
412 		case SETUP_RNG_SEED:
413 			data = early_memremap(pa_data, data_len);
414 			add_bootloader_randomness(data->data, data->len);
415 			/* Zero seed for forward secrecy. */
416 			memzero_explicit(data->data, data->len);
417 			/* Zero length in case we find ourselves back here by accident. */
418 			memzero_explicit(&data->len, sizeof(data->len));
419 			early_memunmap(data, data_len);
420 			break;
421 		default:
422 			break;
423 		}
424 		pa_data = pa_next;
425 	}
426 }
427 
428 static void __init memblock_x86_reserve_range_setup_data(void)
429 {
430 	struct setup_indirect *indirect;
431 	struct setup_data *data;
432 	u64 pa_data, pa_next;
433 	u32 len;
434 
435 	pa_data = boot_params.hdr.setup_data;
436 	while (pa_data) {
437 		data = early_memremap(pa_data, sizeof(*data));
438 		if (!data) {
439 			pr_warn("setup: failed to memremap setup_data entry\n");
440 			return;
441 		}
442 
443 		len = sizeof(*data);
444 		pa_next = data->next;
445 
446 		memblock_reserve(pa_data, sizeof(*data) + data->len);
447 
448 		if (data->type == SETUP_INDIRECT) {
449 			len += data->len;
450 			early_memunmap(data, sizeof(*data));
451 			data = early_memremap(pa_data, len);
452 			if (!data) {
453 				pr_warn("setup: failed to memremap indirect setup_data\n");
454 				return;
455 			}
456 
457 			indirect = (struct setup_indirect *)data->data;
458 
459 			if (indirect->type != SETUP_INDIRECT)
460 				memblock_reserve(indirect->addr, indirect->len);
461 		}
462 
463 		pa_data = pa_next;
464 		early_memunmap(data, len);
465 	}
466 }
467 
468 static void __init arch_reserve_crashkernel(void)
469 {
470 	unsigned long long crash_base, crash_size, low_size = 0;
471 	char *cmdline = boot_command_line;
472 	bool high = false;
473 	int ret;
474 
475 	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
476 		return;
477 
478 	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
479 				&crash_size, &crash_base,
480 				&low_size, &high);
481 	if (ret)
482 		return;
483 
484 	if (xen_pv_domain()) {
485 		pr_info("Ignoring crashkernel for a Xen PV domain\n");
486 		return;
487 	}
488 
489 	reserve_crashkernel_generic(cmdline, crash_size, crash_base,
490 				    low_size, high);
491 }
492 
493 static struct resource standard_io_resources[] = {
494 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
495 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
496 	{ .name = "pic1", .start = 0x20, .end = 0x21,
497 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
498 	{ .name = "timer0", .start = 0x40, .end = 0x43,
499 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
500 	{ .name = "timer1", .start = 0x50, .end = 0x53,
501 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
502 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
503 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
504 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
505 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
506 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
507 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
508 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
509 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
510 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
511 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
512 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
513 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
514 };
515 
516 void __init reserve_standard_io_resources(void)
517 {
518 	int i;
519 
520 	/* request I/O space for devices used on all i[345]86 PCs */
521 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
522 		request_resource(&ioport_resource, &standard_io_resources[i]);
523 
524 }
525 
526 static bool __init snb_gfx_workaround_needed(void)
527 {
528 #ifdef CONFIG_PCI
529 	int i;
530 	u16 vendor, devid;
531 	static const __initconst u16 snb_ids[] = {
532 		0x0102,
533 		0x0112,
534 		0x0122,
535 		0x0106,
536 		0x0116,
537 		0x0126,
538 		0x010a,
539 	};
540 
541 	/* Assume no if something weird is going on with PCI */
542 	if (!early_pci_allowed())
543 		return false;
544 
545 	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
546 	if (vendor != 0x8086)
547 		return false;
548 
549 	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
550 	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
551 		if (devid == snb_ids[i])
552 			return true;
553 #endif
554 
555 	return false;
556 }
557 
558 /*
559  * Sandy Bridge graphics has trouble with certain ranges, exclude
560  * them from allocation.
561  */
562 static void __init trim_snb_memory(void)
563 {
564 	static const __initconst unsigned long bad_pages[] = {
565 		0x20050000,
566 		0x20110000,
567 		0x20130000,
568 		0x20138000,
569 		0x40004000,
570 	};
571 	int i;
572 
573 	if (!snb_gfx_workaround_needed())
574 		return;
575 
576 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
577 
578 	/*
579 	 * SandyBridge integrated graphics devices have a bug that prevents
580 	 * them from accessing certain memory ranges, namely anything below
581 	 * 1M and in the pages listed in bad_pages[] above.
582 	 *
583 	 * To avoid these pages being ever accessed by SNB gfx devices reserve
584 	 * bad_pages that have not already been reserved at boot time.
585 	 * All memory below the 1 MB mark is anyway reserved later during
586 	 * setup_arch(), so there is no need to reserve it here.
587 	 */
588 
589 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
590 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
591 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
592 			       bad_pages[i]);
593 	}
594 }
595 
596 static void __init trim_bios_range(void)
597 {
598 	/*
599 	 * A special case is the first 4Kb of memory;
600 	 * This is a BIOS owned area, not kernel ram, but generally
601 	 * not listed as such in the E820 table.
602 	 *
603 	 * This typically reserves additional memory (64KiB by default)
604 	 * since some BIOSes are known to corrupt low memory.  See the
605 	 * Kconfig help text for X86_RESERVE_LOW.
606 	 */
607 	e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
608 
609 	/*
610 	 * special case: Some BIOSes report the PC BIOS
611 	 * area (640Kb -> 1Mb) as RAM even though it is not.
612 	 * take them out.
613 	 */
614 	e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
615 
616 	e820__update_table(e820_table);
617 }
618 
619 /* called before trim_bios_range() to spare extra sanitize */
620 static void __init e820_add_kernel_range(void)
621 {
622 	u64 start = __pa_symbol(_text);
623 	u64 size = __pa_symbol(_end) - start;
624 
625 	/*
626 	 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
627 	 * attempt to fix it by adding the range. We may have a confused BIOS,
628 	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
629 	 * exclude kernel range. If we really are running on top non-RAM,
630 	 * we will crash later anyways.
631 	 */
632 	if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
633 		return;
634 
635 	pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
636 	e820__range_remove(start, size, E820_TYPE_RAM, 0);
637 	e820__range_add(start, size, E820_TYPE_RAM);
638 }
639 
640 static void __init early_reserve_memory(void)
641 {
642 	/*
643 	 * Reserve the memory occupied by the kernel between _text and
644 	 * __end_of_kernel_reserve symbols. Any kernel sections after the
645 	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
646 	 * separate memblock_reserve() or they will be discarded.
647 	 */
648 	memblock_reserve(__pa_symbol(_text),
649 			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
650 
651 	/*
652 	 * The first 4Kb of memory is a BIOS owned area, but generally it is
653 	 * not listed as such in the E820 table.
654 	 *
655 	 * Reserve the first 64K of memory since some BIOSes are known to
656 	 * corrupt low memory. After the real mode trampoline is allocated the
657 	 * rest of the memory below 640k is reserved.
658 	 *
659 	 * In addition, make sure page 0 is always reserved because on
660 	 * systems with L1TF its contents can be leaked to user processes.
661 	 */
662 	memblock_reserve(0, SZ_64K);
663 
664 	early_reserve_initrd();
665 
666 	memblock_x86_reserve_range_setup_data();
667 
668 	reserve_bios_regions();
669 	trim_snb_memory();
670 }
671 
672 /*
673  * Dump out kernel offset information on panic.
674  */
675 static int
676 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
677 {
678 	if (kaslr_enabled()) {
679 		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
680 			 kaslr_offset(),
681 			 __START_KERNEL,
682 			 __START_KERNEL_map,
683 			 MODULES_VADDR-1);
684 	} else {
685 		pr_emerg("Kernel Offset: disabled\n");
686 	}
687 
688 	return 0;
689 }
690 
691 void x86_configure_nx(void)
692 {
693 	if (boot_cpu_has(X86_FEATURE_NX))
694 		__supported_pte_mask |= _PAGE_NX;
695 	else
696 		__supported_pte_mask &= ~_PAGE_NX;
697 }
698 
699 static void __init x86_report_nx(void)
700 {
701 	if (!boot_cpu_has(X86_FEATURE_NX)) {
702 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
703 		       "missing in CPU!\n");
704 	} else {
705 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
706 		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
707 #else
708 		/* 32bit non-PAE kernel, NX cannot be used */
709 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
710 		       "cannot be enabled: non-PAE kernel!\n");
711 #endif
712 	}
713 }
714 
715 /*
716  * Determine if we were loaded by an EFI loader.  If so, then we have also been
717  * passed the efi memmap, systab, etc., so we should use these data structures
718  * for initialization.  Note, the efi init code path is determined by the
719  * global efi_enabled. This allows the same kernel image to be used on existing
720  * systems (with a traditional BIOS) as well as on EFI systems.
721  */
722 /*
723  * setup_arch - architecture-specific boot-time initializations
724  *
725  * Note: On x86_64, fixmaps are ready for use even before this is called.
726  */
727 
728 void __init setup_arch(char **cmdline_p)
729 {
730 #ifdef CONFIG_X86_32
731 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
732 
733 	/*
734 	 * copy kernel address range established so far and switch
735 	 * to the proper swapper page table
736 	 */
737 	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
738 			initial_page_table + KERNEL_PGD_BOUNDARY,
739 			KERNEL_PGD_PTRS);
740 
741 	load_cr3(swapper_pg_dir);
742 	/*
743 	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
744 	 * a cr3 based tlb flush, so the following __flush_tlb_all()
745 	 * will not flush anything because the CPU quirk which clears
746 	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
747 	 * load_cr3() above the TLB has been flushed already. The
748 	 * quirk is invoked before subsequent calls to __flush_tlb_all()
749 	 * so proper operation is guaranteed.
750 	 */
751 	__flush_tlb_all();
752 #else
753 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
754 	boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
755 #endif
756 
757 #ifdef CONFIG_CMDLINE_BOOL
758 #ifdef CONFIG_CMDLINE_OVERRIDE
759 	strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
760 #else
761 	if (builtin_cmdline[0]) {
762 		/* append boot loader cmdline to builtin */
763 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
764 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
765 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
766 	}
767 #endif
768 #endif
769 
770 	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
771 	*cmdline_p = command_line;
772 
773 	/*
774 	 * If we have OLPC OFW, we might end up relocating the fixmap due to
775 	 * reserve_top(), so do this before touching the ioremap area.
776 	 */
777 	olpc_ofw_detect();
778 
779 	idt_setup_early_traps();
780 	early_cpu_init();
781 	jump_label_init();
782 	static_call_init();
783 	early_ioremap_init();
784 
785 	setup_olpc_ofw_pgd();
786 
787 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
788 	screen_info = boot_params.screen_info;
789 	edid_info = boot_params.edid_info;
790 #ifdef CONFIG_X86_32
791 	apm_info.bios = boot_params.apm_bios_info;
792 	ist_info = boot_params.ist_info;
793 #endif
794 	saved_video_mode = boot_params.hdr.vid_mode;
795 	bootloader_type = boot_params.hdr.type_of_loader;
796 	if ((bootloader_type >> 4) == 0xe) {
797 		bootloader_type &= 0xf;
798 		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
799 	}
800 	bootloader_version  = bootloader_type & 0xf;
801 	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
802 
803 #ifdef CONFIG_BLK_DEV_RAM
804 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
805 #endif
806 #ifdef CONFIG_EFI
807 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
808 		     EFI32_LOADER_SIGNATURE, 4)) {
809 		set_bit(EFI_BOOT, &efi.flags);
810 	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
811 		     EFI64_LOADER_SIGNATURE, 4)) {
812 		set_bit(EFI_BOOT, &efi.flags);
813 		set_bit(EFI_64BIT, &efi.flags);
814 	}
815 #endif
816 
817 	x86_init.oem.arch_setup();
818 
819 	/*
820 	 * Do some memory reservations *before* memory is added to memblock, so
821 	 * memblock allocations won't overwrite it.
822 	 *
823 	 * After this point, everything still needed from the boot loader or
824 	 * firmware or kernel text should be early reserved or marked not RAM in
825 	 * e820. All other memory is free game.
826 	 *
827 	 * This call needs to happen before e820__memory_setup() which calls the
828 	 * xen_memory_setup() on Xen dom0 which relies on the fact that those
829 	 * early reservations have happened already.
830 	 */
831 	early_reserve_memory();
832 
833 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
834 	e820__memory_setup();
835 	parse_setup_data();
836 
837 	copy_edd();
838 
839 	if (!boot_params.hdr.root_flags)
840 		root_mountflags &= ~MS_RDONLY;
841 	setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
842 
843 	code_resource.start = __pa_symbol(_text);
844 	code_resource.end = __pa_symbol(_etext)-1;
845 	rodata_resource.start = __pa_symbol(__start_rodata);
846 	rodata_resource.end = __pa_symbol(__end_rodata)-1;
847 	data_resource.start = __pa_symbol(_sdata);
848 	data_resource.end = __pa_symbol(_edata)-1;
849 	bss_resource.start = __pa_symbol(__bss_start);
850 	bss_resource.end = __pa_symbol(__bss_stop)-1;
851 
852 	/*
853 	 * x86_configure_nx() is called before parse_early_param() to detect
854 	 * whether hardware doesn't support NX (so that the early EHCI debug
855 	 * console setup can safely call set_fixmap()).
856 	 */
857 	x86_configure_nx();
858 
859 	parse_early_param();
860 
861 	if (efi_enabled(EFI_BOOT))
862 		efi_memblock_x86_reserve_range();
863 
864 #ifdef CONFIG_MEMORY_HOTPLUG
865 	/*
866 	 * Memory used by the kernel cannot be hot-removed because Linux
867 	 * cannot migrate the kernel pages. When memory hotplug is
868 	 * enabled, we should prevent memblock from allocating memory
869 	 * for the kernel.
870 	 *
871 	 * ACPI SRAT records all hotpluggable memory ranges. But before
872 	 * SRAT is parsed, we don't know about it.
873 	 *
874 	 * The kernel image is loaded into memory at very early time. We
875 	 * cannot prevent this anyway. So on NUMA system, we set any
876 	 * node the kernel resides in as un-hotpluggable.
877 	 *
878 	 * Since on modern servers, one node could have double-digit
879 	 * gigabytes memory, we can assume the memory around the kernel
880 	 * image is also un-hotpluggable. So before SRAT is parsed, just
881 	 * allocate memory near the kernel image to try the best to keep
882 	 * the kernel away from hotpluggable memory.
883 	 */
884 	if (movable_node_is_enabled())
885 		memblock_set_bottom_up(true);
886 #endif
887 
888 	x86_report_nx();
889 
890 	apic_setup_apic_calls();
891 
892 	if (acpi_mps_check()) {
893 #ifdef CONFIG_X86_LOCAL_APIC
894 		apic_is_disabled = true;
895 #endif
896 		setup_clear_cpu_cap(X86_FEATURE_APIC);
897 	}
898 
899 	e820__reserve_setup_data();
900 	e820__finish_early_params();
901 
902 	if (efi_enabled(EFI_BOOT))
903 		efi_init();
904 
905 	reserve_ibft_region();
906 	x86_init.resources.dmi_setup();
907 
908 	/*
909 	 * VMware detection requires dmi to be available, so this
910 	 * needs to be done after dmi_setup(), for the boot CPU.
911 	 * For some guest types (Xen PV, SEV-SNP, TDX) it is required to be
912 	 * called before cache_bp_init() for setting up MTRR state.
913 	 */
914 	init_hypervisor_platform();
915 
916 	tsc_early_init();
917 	x86_init.resources.probe_roms();
918 
919 	/* after parse_early_param, so could debug it */
920 	insert_resource(&iomem_resource, &code_resource);
921 	insert_resource(&iomem_resource, &rodata_resource);
922 	insert_resource(&iomem_resource, &data_resource);
923 	insert_resource(&iomem_resource, &bss_resource);
924 
925 	e820_add_kernel_range();
926 	trim_bios_range();
927 #ifdef CONFIG_X86_32
928 	if (ppro_with_ram_bug()) {
929 		e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
930 				  E820_TYPE_RESERVED);
931 		e820__update_table(e820_table);
932 		printk(KERN_INFO "fixed physical RAM map:\n");
933 		e820__print_table("bad_ppro");
934 	}
935 #else
936 	early_gart_iommu_check();
937 #endif
938 
939 	/*
940 	 * partially used pages are not usable - thus
941 	 * we are rounding upwards:
942 	 */
943 	max_pfn = e820__end_of_ram_pfn();
944 
945 	/* update e820 for memory not covered by WB MTRRs */
946 	cache_bp_init();
947 	if (mtrr_trim_uncached_memory(max_pfn))
948 		max_pfn = e820__end_of_ram_pfn();
949 
950 	max_possible_pfn = max_pfn;
951 
952 	/*
953 	 * Define random base addresses for memory sections after max_pfn is
954 	 * defined and before each memory section base is used.
955 	 */
956 	kernel_randomize_memory();
957 
958 #ifdef CONFIG_X86_32
959 	/* max_low_pfn get updated here */
960 	find_low_pfn_range();
961 #else
962 	check_x2apic();
963 
964 	/* How many end-of-memory variables you have, grandma! */
965 	/* need this before calling reserve_initrd */
966 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
967 		max_low_pfn = e820__end_of_low_ram_pfn();
968 	else
969 		max_low_pfn = max_pfn;
970 
971 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
972 #endif
973 
974 	/* Find and reserve MPTABLE area */
975 	x86_init.mpparse.find_mptable();
976 
977 	early_alloc_pgt_buf();
978 
979 	/*
980 	 * Need to conclude brk, before e820__memblock_setup()
981 	 * it could use memblock_find_in_range, could overlap with
982 	 * brk area.
983 	 */
984 	reserve_brk();
985 
986 	cleanup_highmap();
987 
988 	memblock_set_current_limit(ISA_END_ADDRESS);
989 	e820__memblock_setup();
990 
991 	/*
992 	 * Needs to run after memblock setup because it needs the physical
993 	 * memory size.
994 	 */
995 	mem_encrypt_setup_arch();
996 	cc_random_init();
997 
998 	efi_fake_memmap();
999 	efi_find_mirror();
1000 	efi_esrt_init();
1001 	efi_mokvar_table_init();
1002 
1003 	/*
1004 	 * The EFI specification says that boot service code won't be
1005 	 * called after ExitBootServices(). This is, in fact, a lie.
1006 	 */
1007 	efi_reserve_boot_services();
1008 
1009 	/* preallocate 4k for mptable mpc */
1010 	e820__memblock_alloc_reserved_mpc_new();
1011 
1012 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1013 	setup_bios_corruption_check();
1014 #endif
1015 
1016 #ifdef CONFIG_X86_32
1017 	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1018 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1019 #endif
1020 
1021 	/*
1022 	 * Find free memory for the real mode trampoline and place it there. If
1023 	 * there is not enough free memory under 1M, on EFI-enabled systems
1024 	 * there will be additional attempt to reclaim the memory for the real
1025 	 * mode trampoline at efi_free_boot_services().
1026 	 *
1027 	 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1028 	 * are known to corrupt low memory and several hundred kilobytes are not
1029 	 * worth complex detection what memory gets clobbered. Windows does the
1030 	 * same thing for very similar reasons.
1031 	 *
1032 	 * Moreover, on machines with SandyBridge graphics or in setups that use
1033 	 * crashkernel the entire 1M is reserved anyway.
1034 	 *
1035 	 * Note the host kernel TDX also requires the first 1MB being reserved.
1036 	 */
1037 	x86_platform.realmode_reserve();
1038 
1039 	init_mem_mapping();
1040 
1041 	idt_setup_early_pf();
1042 
1043 	/*
1044 	 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1045 	 * with the current CR4 value.  This may not be necessary, but
1046 	 * auditing all the early-boot CR4 manipulation would be needed to
1047 	 * rule it out.
1048 	 *
1049 	 * Mask off features that don't work outside long mode (just
1050 	 * PCIDE for now).
1051 	 */
1052 	mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1053 
1054 	memblock_set_current_limit(get_max_mapped());
1055 
1056 	/*
1057 	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1058 	 */
1059 
1060 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1061 	if (init_ohci1394_dma_early)
1062 		init_ohci1394_dma_on_all_controllers();
1063 #endif
1064 	/* Allocate bigger log buffer */
1065 	setup_log_buf(1);
1066 
1067 	if (efi_enabled(EFI_BOOT)) {
1068 		switch (boot_params.secure_boot) {
1069 		case efi_secureboot_mode_disabled:
1070 			pr_info("Secure boot disabled\n");
1071 			break;
1072 		case efi_secureboot_mode_enabled:
1073 			pr_info("Secure boot enabled\n");
1074 			break;
1075 		default:
1076 			pr_info("Secure boot could not be determined\n");
1077 			break;
1078 		}
1079 	}
1080 
1081 	reserve_initrd();
1082 
1083 	acpi_table_upgrade();
1084 	/* Look for ACPI tables and reserve memory occupied by them. */
1085 	acpi_boot_table_init();
1086 
1087 	vsmp_init();
1088 
1089 	io_delay_init();
1090 
1091 	early_platform_quirks();
1092 
1093 	/* Some platforms need the APIC registered for NUMA configuration */
1094 	early_acpi_boot_init();
1095 	x86_init.mpparse.early_parse_smp_cfg();
1096 
1097 	x86_flattree_get_config();
1098 
1099 	initmem_init();
1100 	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1101 
1102 	if (boot_cpu_has(X86_FEATURE_GBPAGES))
1103 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1104 
1105 	/*
1106 	 * Reserve memory for crash kernel after SRAT is parsed so that it
1107 	 * won't consume hotpluggable memory.
1108 	 */
1109 	arch_reserve_crashkernel();
1110 
1111 	if (!early_xdbc_setup_hardware())
1112 		early_xdbc_register_console();
1113 
1114 	x86_init.paging.pagetable_init();
1115 
1116 	kasan_init();
1117 
1118 	/*
1119 	 * Sync back kernel address range.
1120 	 *
1121 	 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1122 	 * this call?
1123 	 */
1124 	sync_initial_page_table();
1125 
1126 	tboot_probe();
1127 
1128 	map_vsyscall();
1129 
1130 	x86_32_probe_apic();
1131 
1132 	early_quirks();
1133 
1134 	topology_apply_cmdline_limits_early();
1135 
1136 	/*
1137 	 * Parse SMP configuration. Try ACPI first and then the platform
1138 	 * specific parser.
1139 	 */
1140 	acpi_boot_init();
1141 	x86_init.mpparse.parse_smp_cfg();
1142 
1143 	/* Last opportunity to detect and map the local APIC */
1144 	init_apic_mappings();
1145 
1146 	topology_init_possible_cpus();
1147 
1148 	init_cpu_to_node();
1149 	init_gi_nodes();
1150 
1151 	io_apic_init_mappings();
1152 
1153 	x86_init.hyper.guest_late_init();
1154 
1155 	e820__reserve_resources();
1156 	e820__register_nosave_regions(max_pfn);
1157 
1158 	x86_init.resources.reserve_resources();
1159 
1160 	e820__setup_pci_gap();
1161 
1162 #ifdef CONFIG_VT
1163 #if defined(CONFIG_VGA_CONSOLE)
1164 	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1165 		vgacon_register_screen(&screen_info);
1166 #endif
1167 #endif
1168 	x86_init.oem.banner();
1169 
1170 	x86_init.timers.wallclock_init();
1171 
1172 	/*
1173 	 * This needs to run before setup_local_APIC() which soft-disables the
1174 	 * local APIC temporarily and that masks the thermal LVT interrupt,
1175 	 * leading to softlockups on machines which have configured SMI
1176 	 * interrupt delivery.
1177 	 */
1178 	therm_lvt_init();
1179 
1180 	mcheck_init();
1181 
1182 	register_refined_jiffies(CLOCK_TICK_RATE);
1183 
1184 #ifdef CONFIG_EFI
1185 	if (efi_enabled(EFI_BOOT))
1186 		efi_apply_memmap_quirks();
1187 #endif
1188 
1189 	unwind_init();
1190 }
1191 
1192 #ifdef CONFIG_X86_32
1193 
1194 static struct resource video_ram_resource = {
1195 	.name	= "Video RAM area",
1196 	.start	= 0xa0000,
1197 	.end	= 0xbffff,
1198 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1199 };
1200 
1201 void __init i386_reserve_resources(void)
1202 {
1203 	request_resource(&iomem_resource, &video_ram_resource);
1204 	reserve_standard_io_resources();
1205 }
1206 
1207 #endif /* CONFIG_X86_32 */
1208 
1209 static struct notifier_block kernel_offset_notifier = {
1210 	.notifier_call = dump_kernel_offset
1211 };
1212 
1213 static int __init register_kernel_offset_dumper(void)
1214 {
1215 	atomic_notifier_chain_register(&panic_notifier_list,
1216 					&kernel_offset_notifier);
1217 	return 0;
1218 }
1219 __initcall(register_kernel_offset_dumper);
1220 
1221 #ifdef CONFIG_HOTPLUG_CPU
1222 bool arch_cpu_is_hotpluggable(int cpu)
1223 {
1224 	return cpu > 0;
1225 }
1226 #endif /* CONFIG_HOTPLUG_CPU */
1227