xref: /openbmc/linux/arch/x86/kernel/setup.c (revision 8957261c)
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/crash_dump.h>
11 #include <linux/dma-map-ops.h>
12 #include <linux/dmi.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/cpu.h>
40 #include <asm/efi.h>
41 #include <asm/gart.h>
42 #include <asm/hypervisor.h>
43 #include <asm/io_apic.h>
44 #include <asm/kasan.h>
45 #include <asm/kaslr.h>
46 #include <asm/mce.h>
47 #include <asm/memtype.h>
48 #include <asm/mtrr.h>
49 #include <asm/realmode.h>
50 #include <asm/olpc_ofw.h>
51 #include <asm/pci-direct.h>
52 #include <asm/prom.h>
53 #include <asm/proto.h>
54 #include <asm/thermal.h>
55 #include <asm/unwind.h>
56 #include <asm/vsyscall.h>
57 #include <linux/vmalloc.h>
58 
59 /*
60  * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
61  * max_pfn_mapped:     highest directly mapped pfn > 4 GB
62  *
63  * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
64  * represented by pfn_mapped[].
65  */
66 unsigned long max_low_pfn_mapped;
67 unsigned long max_pfn_mapped;
68 
69 #ifdef CONFIG_DMI
70 RESERVE_BRK(dmi_alloc, 65536);
71 #endif
72 
73 
74 unsigned long _brk_start = (unsigned long)__brk_base;
75 unsigned long _brk_end   = (unsigned long)__brk_base;
76 
77 struct boot_params boot_params;
78 
79 /*
80  * These are the four main kernel memory regions, we put them into
81  * the resource tree so that kdump tools and other debugging tools
82  * recover it:
83  */
84 
85 static struct resource rodata_resource = {
86 	.name	= "Kernel rodata",
87 	.start	= 0,
88 	.end	= 0,
89 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
90 };
91 
92 static struct resource data_resource = {
93 	.name	= "Kernel data",
94 	.start	= 0,
95 	.end	= 0,
96 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
97 };
98 
99 static struct resource code_resource = {
100 	.name	= "Kernel code",
101 	.start	= 0,
102 	.end	= 0,
103 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
104 };
105 
106 static struct resource bss_resource = {
107 	.name	= "Kernel bss",
108 	.start	= 0,
109 	.end	= 0,
110 	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
111 };
112 
113 
114 #ifdef CONFIG_X86_32
115 /* CPU data as detected by the assembly code in head_32.S */
116 struct cpuinfo_x86 new_cpu_data;
117 
118 struct apm_info apm_info;
119 EXPORT_SYMBOL(apm_info);
120 
121 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
122 	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
123 struct ist_info ist_info;
124 EXPORT_SYMBOL(ist_info);
125 #else
126 struct ist_info ist_info;
127 #endif
128 
129 #endif
130 
131 struct cpuinfo_x86 boot_cpu_data __read_mostly;
132 EXPORT_SYMBOL(boot_cpu_data);
133 
134 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
135 __visible unsigned long mmu_cr4_features __ro_after_init;
136 #else
137 __visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
138 #endif
139 
140 #ifdef CONFIG_IMA
141 static phys_addr_t ima_kexec_buffer_phys;
142 static size_t ima_kexec_buffer_size;
143 #endif
144 
145 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
146 int bootloader_type, bootloader_version;
147 
148 /*
149  * Setup options
150  */
151 struct screen_info screen_info;
152 EXPORT_SYMBOL(screen_info);
153 struct edid_info edid_info;
154 EXPORT_SYMBOL_GPL(edid_info);
155 
156 extern int root_mountflags;
157 
158 unsigned long saved_video_mode;
159 
160 #define RAMDISK_IMAGE_START_MASK	0x07FF
161 #define RAMDISK_PROMPT_FLAG		0x8000
162 #define RAMDISK_LOAD_FLAG		0x4000
163 
164 static char __initdata command_line[COMMAND_LINE_SIZE];
165 #ifdef CONFIG_CMDLINE_BOOL
166 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
167 #endif
168 
169 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
170 struct edd edd;
171 #ifdef CONFIG_EDD_MODULE
172 EXPORT_SYMBOL(edd);
173 #endif
174 /**
175  * copy_edd() - Copy the BIOS EDD information
176  *              from boot_params into a safe place.
177  *
178  */
179 static inline void __init copy_edd(void)
180 {
181      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
182 	    sizeof(edd.mbr_signature));
183      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
184      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
185      edd.edd_info_nr = boot_params.eddbuf_entries;
186 }
187 #else
188 static inline void __init copy_edd(void)
189 {
190 }
191 #endif
192 
193 void * __init extend_brk(size_t size, size_t align)
194 {
195 	size_t mask = align - 1;
196 	void *ret;
197 
198 	BUG_ON(_brk_start == 0);
199 	BUG_ON(align & mask);
200 
201 	_brk_end = (_brk_end + mask) & ~mask;
202 	BUG_ON((char *)(_brk_end + size) > __brk_limit);
203 
204 	ret = (void *)_brk_end;
205 	_brk_end += size;
206 
207 	memset(ret, 0, size);
208 
209 	return ret;
210 }
211 
212 #ifdef CONFIG_X86_32
213 static void __init cleanup_highmap(void)
214 {
215 }
216 #endif
217 
218 static void __init reserve_brk(void)
219 {
220 	if (_brk_end > _brk_start)
221 		memblock_reserve(__pa_symbol(_brk_start),
222 				 _brk_end - _brk_start);
223 
224 	/* Mark brk area as locked down and no longer taking any
225 	   new allocations */
226 	_brk_start = 0;
227 }
228 
229 u64 relocated_ramdisk;
230 
231 #ifdef CONFIG_BLK_DEV_INITRD
232 
233 static u64 __init get_ramdisk_image(void)
234 {
235 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
236 
237 	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
238 
239 	if (ramdisk_image == 0)
240 		ramdisk_image = phys_initrd_start;
241 
242 	return ramdisk_image;
243 }
244 static u64 __init get_ramdisk_size(void)
245 {
246 	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
247 
248 	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
249 
250 	if (ramdisk_size == 0)
251 		ramdisk_size = phys_initrd_size;
252 
253 	return ramdisk_size;
254 }
255 
256 static void __init relocate_initrd(void)
257 {
258 	/* Assume only end is not page aligned */
259 	u64 ramdisk_image = get_ramdisk_image();
260 	u64 ramdisk_size  = get_ramdisk_size();
261 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
262 
263 	/* We need to move the initrd down into directly mapped mem */
264 	relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
265 						      PFN_PHYS(max_pfn_mapped));
266 	if (!relocated_ramdisk)
267 		panic("Cannot find place for new RAMDISK of size %lld\n",
268 		      ramdisk_size);
269 
270 	initrd_start = relocated_ramdisk + PAGE_OFFSET;
271 	initrd_end   = initrd_start + ramdisk_size;
272 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
273 	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
274 
275 	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
276 
277 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
278 		" [mem %#010llx-%#010llx]\n",
279 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
280 		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
281 }
282 
283 static void __init early_reserve_initrd(void)
284 {
285 	/* Assume only end is not page aligned */
286 	u64 ramdisk_image = get_ramdisk_image();
287 	u64 ramdisk_size  = get_ramdisk_size();
288 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
289 
290 	if (!boot_params.hdr.type_of_loader ||
291 	    !ramdisk_image || !ramdisk_size)
292 		return;		/* No initrd provided by bootloader */
293 
294 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
295 }
296 
297 static void __init reserve_initrd(void)
298 {
299 	/* Assume only end is not page aligned */
300 	u64 ramdisk_image = get_ramdisk_image();
301 	u64 ramdisk_size  = get_ramdisk_size();
302 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
303 
304 	if (!boot_params.hdr.type_of_loader ||
305 	    !ramdisk_image || !ramdisk_size)
306 		return;		/* No initrd provided by bootloader */
307 
308 	initrd_start = 0;
309 
310 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
311 			ramdisk_end - 1);
312 
313 	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
314 				PFN_DOWN(ramdisk_end))) {
315 		/* All are mapped, easy case */
316 		initrd_start = ramdisk_image + PAGE_OFFSET;
317 		initrd_end = initrd_start + ramdisk_size;
318 		return;
319 	}
320 
321 	relocate_initrd();
322 
323 	memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image);
324 }
325 
326 #else
327 static void __init early_reserve_initrd(void)
328 {
329 }
330 static void __init reserve_initrd(void)
331 {
332 }
333 #endif /* CONFIG_BLK_DEV_INITRD */
334 
335 static void __init add_early_ima_buffer(u64 phys_addr)
336 {
337 #ifdef CONFIG_IMA
338 	struct ima_setup_data *data;
339 
340 	data = early_memremap(phys_addr + sizeof(struct setup_data), sizeof(*data));
341 	if (!data) {
342 		pr_warn("setup: failed to memremap ima_setup_data entry\n");
343 		return;
344 	}
345 
346 	if (data->size) {
347 		memblock_reserve(data->addr, data->size);
348 		ima_kexec_buffer_phys = data->addr;
349 		ima_kexec_buffer_size = data->size;
350 	}
351 
352 	early_memunmap(data, sizeof(*data));
353 #else
354 	pr_warn("Passed IMA kexec data, but CONFIG_IMA not set. Ignoring.\n");
355 #endif
356 }
357 
358 #if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE)
359 int __init ima_free_kexec_buffer(void)
360 {
361 	int rc;
362 
363 	if (!ima_kexec_buffer_size)
364 		return -ENOENT;
365 
366 	rc = memblock_phys_free(ima_kexec_buffer_phys,
367 				ima_kexec_buffer_size);
368 	if (rc)
369 		return rc;
370 
371 	ima_kexec_buffer_phys = 0;
372 	ima_kexec_buffer_size = 0;
373 
374 	return 0;
375 }
376 
377 int __init ima_get_kexec_buffer(void **addr, size_t *size)
378 {
379 	if (!ima_kexec_buffer_size)
380 		return -ENOENT;
381 
382 	*addr = __va(ima_kexec_buffer_phys);
383 	*size = ima_kexec_buffer_size;
384 
385 	return 0;
386 }
387 #endif
388 
389 static void __init parse_setup_data(void)
390 {
391 	struct setup_data *data;
392 	u64 pa_data, pa_next;
393 
394 	pa_data = boot_params.hdr.setup_data;
395 	while (pa_data) {
396 		u32 data_len, data_type;
397 
398 		data = early_memremap(pa_data, sizeof(*data));
399 		data_len = data->len + sizeof(struct setup_data);
400 		data_type = data->type;
401 		pa_next = data->next;
402 		early_memunmap(data, sizeof(*data));
403 
404 		switch (data_type) {
405 		case SETUP_E820_EXT:
406 			e820__memory_setup_extended(pa_data, data_len);
407 			break;
408 		case SETUP_DTB:
409 			add_dtb(pa_data);
410 			break;
411 		case SETUP_EFI:
412 			parse_efi_setup(pa_data, data_len);
413 			break;
414 		case SETUP_IMA:
415 			add_early_ima_buffer(pa_data);
416 			break;
417 		case SETUP_RNG_SEED:
418 			data = early_memremap(pa_data, data_len);
419 			add_bootloader_randomness(data->data, data->len);
420 			/* Zero seed for forward secrecy. */
421 			memzero_explicit(data->data, data->len);
422 			/* Zero length in case we find ourselves back here by accident. */
423 			memzero_explicit(&data->len, sizeof(data->len));
424 			early_memunmap(data, data_len);
425 			break;
426 		default:
427 			break;
428 		}
429 		pa_data = pa_next;
430 	}
431 }
432 
433 static void __init memblock_x86_reserve_range_setup_data(void)
434 {
435 	struct setup_indirect *indirect;
436 	struct setup_data *data;
437 	u64 pa_data, pa_next;
438 	u32 len;
439 
440 	pa_data = boot_params.hdr.setup_data;
441 	while (pa_data) {
442 		data = early_memremap(pa_data, sizeof(*data));
443 		if (!data) {
444 			pr_warn("setup: failed to memremap setup_data entry\n");
445 			return;
446 		}
447 
448 		len = sizeof(*data);
449 		pa_next = data->next;
450 
451 		memblock_reserve(pa_data, sizeof(*data) + data->len);
452 
453 		if (data->type == SETUP_INDIRECT) {
454 			len += data->len;
455 			early_memunmap(data, sizeof(*data));
456 			data = early_memremap(pa_data, len);
457 			if (!data) {
458 				pr_warn("setup: failed to memremap indirect setup_data\n");
459 				return;
460 			}
461 
462 			indirect = (struct setup_indirect *)data->data;
463 
464 			if (indirect->type != SETUP_INDIRECT)
465 				memblock_reserve(indirect->addr, indirect->len);
466 		}
467 
468 		pa_data = pa_next;
469 		early_memunmap(data, len);
470 	}
471 }
472 
473 /*
474  * --------- Crashkernel reservation ------------------------------
475  */
476 
477 /* 16M alignment for crash kernel regions */
478 #define CRASH_ALIGN		SZ_16M
479 
480 /*
481  * Keep the crash kernel below this limit.
482  *
483  * Earlier 32-bits kernels would limit the kernel to the low 512 MB range
484  * due to mapping restrictions.
485  *
486  * 64-bit kdump kernels need to be restricted to be under 64 TB, which is
487  * the upper limit of system RAM in 4-level paging mode. Since the kdump
488  * jump could be from 5-level paging to 4-level paging, the jump will fail if
489  * the kernel is put above 64 TB, and during the 1st kernel bootup there's
490  * no good way to detect the paging mode of the target kernel which will be
491  * loaded for dumping.
492  */
493 #ifdef CONFIG_X86_32
494 # define CRASH_ADDR_LOW_MAX	SZ_512M
495 # define CRASH_ADDR_HIGH_MAX	SZ_512M
496 #else
497 # define CRASH_ADDR_LOW_MAX	SZ_4G
498 # define CRASH_ADDR_HIGH_MAX	SZ_64T
499 #endif
500 
501 static int __init reserve_crashkernel_low(void)
502 {
503 #ifdef CONFIG_X86_64
504 	unsigned long long base, low_base = 0, low_size = 0;
505 	unsigned long low_mem_limit;
506 	int ret;
507 
508 	low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
509 
510 	/* crashkernel=Y,low */
511 	ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base);
512 	if (ret) {
513 		/*
514 		 * two parts from kernel/dma/swiotlb.c:
515 		 * -swiotlb size: user-specified with swiotlb= or default.
516 		 *
517 		 * -swiotlb overflow buffer: now hardcoded to 32k. We round it
518 		 * to 8M for other buffers that may need to stay low too. Also
519 		 * make sure we allocate enough extra low memory so that we
520 		 * don't run out of DMA buffers for 32-bit devices.
521 		 */
522 		low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20);
523 	} else {
524 		/* passed with crashkernel=0,low ? */
525 		if (!low_size)
526 			return 0;
527 	}
528 
529 	low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
530 	if (!low_base) {
531 		pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
532 		       (unsigned long)(low_size >> 20));
533 		return -ENOMEM;
534 	}
535 
536 	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
537 		(unsigned long)(low_size >> 20),
538 		(unsigned long)(low_base >> 20),
539 		(unsigned long)(low_mem_limit >> 20));
540 
541 	crashk_low_res.start = low_base;
542 	crashk_low_res.end   = low_base + low_size - 1;
543 	insert_resource(&iomem_resource, &crashk_low_res);
544 #endif
545 	return 0;
546 }
547 
548 static void __init reserve_crashkernel(void)
549 {
550 	unsigned long long crash_size, crash_base, total_mem;
551 	bool high = false;
552 	int ret;
553 
554 	if (!IS_ENABLED(CONFIG_KEXEC_CORE))
555 		return;
556 
557 	total_mem = memblock_phys_mem_size();
558 
559 	/* crashkernel=XM */
560 	ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base);
561 	if (ret != 0 || crash_size <= 0) {
562 		/* crashkernel=X,high */
563 		ret = parse_crashkernel_high(boot_command_line, total_mem,
564 					     &crash_size, &crash_base);
565 		if (ret != 0 || crash_size <= 0)
566 			return;
567 		high = true;
568 	}
569 
570 	if (xen_pv_domain()) {
571 		pr_info("Ignoring crashkernel for a Xen PV domain\n");
572 		return;
573 	}
574 
575 	/* 0 means: find the address automatically */
576 	if (!crash_base) {
577 		/*
578 		 * Set CRASH_ADDR_LOW_MAX upper bound for crash memory,
579 		 * crashkernel=x,high reserves memory over 4G, also allocates
580 		 * 256M extra low memory for DMA buffers and swiotlb.
581 		 * But the extra memory is not required for all machines.
582 		 * So try low memory first and fall back to high memory
583 		 * unless "crashkernel=size[KMG],high" is specified.
584 		 */
585 		if (!high)
586 			crash_base = memblock_phys_alloc_range(crash_size,
587 						CRASH_ALIGN, CRASH_ALIGN,
588 						CRASH_ADDR_LOW_MAX);
589 		if (!crash_base)
590 			crash_base = memblock_phys_alloc_range(crash_size,
591 						CRASH_ALIGN, CRASH_ALIGN,
592 						CRASH_ADDR_HIGH_MAX);
593 		if (!crash_base) {
594 			pr_info("crashkernel reservation failed - No suitable area found.\n");
595 			return;
596 		}
597 	} else {
598 		unsigned long long start;
599 
600 		start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
601 						  crash_base + crash_size);
602 		if (start != crash_base) {
603 			pr_info("crashkernel reservation failed - memory is in use.\n");
604 			return;
605 		}
606 	}
607 
608 	if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
609 		memblock_phys_free(crash_base, crash_size);
610 		return;
611 	}
612 
613 	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
614 		(unsigned long)(crash_size >> 20),
615 		(unsigned long)(crash_base >> 20),
616 		(unsigned long)(total_mem >> 20));
617 
618 	crashk_res.start = crash_base;
619 	crashk_res.end   = crash_base + crash_size - 1;
620 	insert_resource(&iomem_resource, &crashk_res);
621 }
622 
623 static struct resource standard_io_resources[] = {
624 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
625 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
626 	{ .name = "pic1", .start = 0x20, .end = 0x21,
627 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
628 	{ .name = "timer0", .start = 0x40, .end = 0x43,
629 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
630 	{ .name = "timer1", .start = 0x50, .end = 0x53,
631 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
632 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
633 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
634 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
635 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
636 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
637 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
638 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
639 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
640 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
641 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
642 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
643 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
644 };
645 
646 void __init reserve_standard_io_resources(void)
647 {
648 	int i;
649 
650 	/* request I/O space for devices used on all i[345]86 PCs */
651 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
652 		request_resource(&ioport_resource, &standard_io_resources[i]);
653 
654 }
655 
656 static bool __init snb_gfx_workaround_needed(void)
657 {
658 #ifdef CONFIG_PCI
659 	int i;
660 	u16 vendor, devid;
661 	static const __initconst u16 snb_ids[] = {
662 		0x0102,
663 		0x0112,
664 		0x0122,
665 		0x0106,
666 		0x0116,
667 		0x0126,
668 		0x010a,
669 	};
670 
671 	/* Assume no if something weird is going on with PCI */
672 	if (!early_pci_allowed())
673 		return false;
674 
675 	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
676 	if (vendor != 0x8086)
677 		return false;
678 
679 	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
680 	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
681 		if (devid == snb_ids[i])
682 			return true;
683 #endif
684 
685 	return false;
686 }
687 
688 /*
689  * Sandy Bridge graphics has trouble with certain ranges, exclude
690  * them from allocation.
691  */
692 static void __init trim_snb_memory(void)
693 {
694 	static const __initconst unsigned long bad_pages[] = {
695 		0x20050000,
696 		0x20110000,
697 		0x20130000,
698 		0x20138000,
699 		0x40004000,
700 	};
701 	int i;
702 
703 	if (!snb_gfx_workaround_needed())
704 		return;
705 
706 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
707 
708 	/*
709 	 * SandyBridge integrated graphics devices have a bug that prevents
710 	 * them from accessing certain memory ranges, namely anything below
711 	 * 1M and in the pages listed in bad_pages[] above.
712 	 *
713 	 * To avoid these pages being ever accessed by SNB gfx devices reserve
714 	 * bad_pages that have not already been reserved at boot time.
715 	 * All memory below the 1 MB mark is anyway reserved later during
716 	 * setup_arch(), so there is no need to reserve it here.
717 	 */
718 
719 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
720 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
721 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
722 			       bad_pages[i]);
723 	}
724 }
725 
726 static void __init trim_bios_range(void)
727 {
728 	/*
729 	 * A special case is the first 4Kb of memory;
730 	 * This is a BIOS owned area, not kernel ram, but generally
731 	 * not listed as such in the E820 table.
732 	 *
733 	 * This typically reserves additional memory (64KiB by default)
734 	 * since some BIOSes are known to corrupt low memory.  See the
735 	 * Kconfig help text for X86_RESERVE_LOW.
736 	 */
737 	e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
738 
739 	/*
740 	 * special case: Some BIOSes report the PC BIOS
741 	 * area (640Kb -> 1Mb) as RAM even though it is not.
742 	 * take them out.
743 	 */
744 	e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
745 
746 	e820__update_table(e820_table);
747 }
748 
749 /* called before trim_bios_range() to spare extra sanitize */
750 static void __init e820_add_kernel_range(void)
751 {
752 	u64 start = __pa_symbol(_text);
753 	u64 size = __pa_symbol(_end) - start;
754 
755 	/*
756 	 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
757 	 * attempt to fix it by adding the range. We may have a confused BIOS,
758 	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
759 	 * exclude kernel range. If we really are running on top non-RAM,
760 	 * we will crash later anyways.
761 	 */
762 	if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
763 		return;
764 
765 	pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
766 	e820__range_remove(start, size, E820_TYPE_RAM, 0);
767 	e820__range_add(start, size, E820_TYPE_RAM);
768 }
769 
770 static void __init early_reserve_memory(void)
771 {
772 	/*
773 	 * Reserve the memory occupied by the kernel between _text and
774 	 * __end_of_kernel_reserve symbols. Any kernel sections after the
775 	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
776 	 * separate memblock_reserve() or they will be discarded.
777 	 */
778 	memblock_reserve(__pa_symbol(_text),
779 			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
780 
781 	/*
782 	 * The first 4Kb of memory is a BIOS owned area, but generally it is
783 	 * not listed as such in the E820 table.
784 	 *
785 	 * Reserve the first 64K of memory since some BIOSes are known to
786 	 * corrupt low memory. After the real mode trampoline is allocated the
787 	 * rest of the memory below 640k is reserved.
788 	 *
789 	 * In addition, make sure page 0 is always reserved because on
790 	 * systems with L1TF its contents can be leaked to user processes.
791 	 */
792 	memblock_reserve(0, SZ_64K);
793 
794 	early_reserve_initrd();
795 
796 	memblock_x86_reserve_range_setup_data();
797 
798 	reserve_bios_regions();
799 	trim_snb_memory();
800 }
801 
802 /*
803  * Dump out kernel offset information on panic.
804  */
805 static int
806 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
807 {
808 	if (kaslr_enabled()) {
809 		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
810 			 kaslr_offset(),
811 			 __START_KERNEL,
812 			 __START_KERNEL_map,
813 			 MODULES_VADDR-1);
814 	} else {
815 		pr_emerg("Kernel Offset: disabled\n");
816 	}
817 
818 	return 0;
819 }
820 
821 void x86_configure_nx(void)
822 {
823 	if (boot_cpu_has(X86_FEATURE_NX))
824 		__supported_pte_mask |= _PAGE_NX;
825 	else
826 		__supported_pte_mask &= ~_PAGE_NX;
827 }
828 
829 static void __init x86_report_nx(void)
830 {
831 	if (!boot_cpu_has(X86_FEATURE_NX)) {
832 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
833 		       "missing in CPU!\n");
834 	} else {
835 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
836 		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
837 #else
838 		/* 32bit non-PAE kernel, NX cannot be used */
839 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
840 		       "cannot be enabled: non-PAE kernel!\n");
841 #endif
842 	}
843 }
844 
845 /*
846  * Determine if we were loaded by an EFI loader.  If so, then we have also been
847  * passed the efi memmap, systab, etc., so we should use these data structures
848  * for initialization.  Note, the efi init code path is determined by the
849  * global efi_enabled. This allows the same kernel image to be used on existing
850  * systems (with a traditional BIOS) as well as on EFI systems.
851  */
852 /*
853  * setup_arch - architecture-specific boot-time initializations
854  *
855  * Note: On x86_64, fixmaps are ready for use even before this is called.
856  */
857 
858 void __init setup_arch(char **cmdline_p)
859 {
860 #ifdef CONFIG_X86_32
861 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
862 
863 	/*
864 	 * copy kernel address range established so far and switch
865 	 * to the proper swapper page table
866 	 */
867 	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
868 			initial_page_table + KERNEL_PGD_BOUNDARY,
869 			KERNEL_PGD_PTRS);
870 
871 	load_cr3(swapper_pg_dir);
872 	/*
873 	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
874 	 * a cr3 based tlb flush, so the following __flush_tlb_all()
875 	 * will not flush anything because the CPU quirk which clears
876 	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
877 	 * load_cr3() above the TLB has been flushed already. The
878 	 * quirk is invoked before subsequent calls to __flush_tlb_all()
879 	 * so proper operation is guaranteed.
880 	 */
881 	__flush_tlb_all();
882 #else
883 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
884 	boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
885 #endif
886 
887 	/*
888 	 * If we have OLPC OFW, we might end up relocating the fixmap due to
889 	 * reserve_top(), so do this before touching the ioremap area.
890 	 */
891 	olpc_ofw_detect();
892 
893 	idt_setup_early_traps();
894 	early_cpu_init();
895 	jump_label_init();
896 	static_call_init();
897 	early_ioremap_init();
898 
899 	setup_olpc_ofw_pgd();
900 
901 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
902 	screen_info = boot_params.screen_info;
903 	edid_info = boot_params.edid_info;
904 #ifdef CONFIG_X86_32
905 	apm_info.bios = boot_params.apm_bios_info;
906 	ist_info = boot_params.ist_info;
907 #endif
908 	saved_video_mode = boot_params.hdr.vid_mode;
909 	bootloader_type = boot_params.hdr.type_of_loader;
910 	if ((bootloader_type >> 4) == 0xe) {
911 		bootloader_type &= 0xf;
912 		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
913 	}
914 	bootloader_version  = bootloader_type & 0xf;
915 	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
916 
917 #ifdef CONFIG_BLK_DEV_RAM
918 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
919 #endif
920 #ifdef CONFIG_EFI
921 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
922 		     EFI32_LOADER_SIGNATURE, 4)) {
923 		set_bit(EFI_BOOT, &efi.flags);
924 	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
925 		     EFI64_LOADER_SIGNATURE, 4)) {
926 		set_bit(EFI_BOOT, &efi.flags);
927 		set_bit(EFI_64BIT, &efi.flags);
928 	}
929 #endif
930 
931 	x86_init.oem.arch_setup();
932 
933 	/*
934 	 * Do some memory reservations *before* memory is added to memblock, so
935 	 * memblock allocations won't overwrite it.
936 	 *
937 	 * After this point, everything still needed from the boot loader or
938 	 * firmware or kernel text should be early reserved or marked not RAM in
939 	 * e820. All other memory is free game.
940 	 *
941 	 * This call needs to happen before e820__memory_setup() which calls the
942 	 * xen_memory_setup() on Xen dom0 which relies on the fact that those
943 	 * early reservations have happened already.
944 	 */
945 	early_reserve_memory();
946 
947 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
948 	e820__memory_setup();
949 	parse_setup_data();
950 
951 	copy_edd();
952 
953 	if (!boot_params.hdr.root_flags)
954 		root_mountflags &= ~MS_RDONLY;
955 	setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
956 
957 	code_resource.start = __pa_symbol(_text);
958 	code_resource.end = __pa_symbol(_etext)-1;
959 	rodata_resource.start = __pa_symbol(__start_rodata);
960 	rodata_resource.end = __pa_symbol(__end_rodata)-1;
961 	data_resource.start = __pa_symbol(_sdata);
962 	data_resource.end = __pa_symbol(_edata)-1;
963 	bss_resource.start = __pa_symbol(__bss_start);
964 	bss_resource.end = __pa_symbol(__bss_stop)-1;
965 
966 #ifdef CONFIG_CMDLINE_BOOL
967 #ifdef CONFIG_CMDLINE_OVERRIDE
968 	strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
969 #else
970 	if (builtin_cmdline[0]) {
971 		/* append boot loader cmdline to builtin */
972 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
973 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
974 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
975 	}
976 #endif
977 #endif
978 
979 	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
980 	*cmdline_p = command_line;
981 
982 	/*
983 	 * x86_configure_nx() is called before parse_early_param() to detect
984 	 * whether hardware doesn't support NX (so that the early EHCI debug
985 	 * console setup can safely call set_fixmap()).
986 	 */
987 	x86_configure_nx();
988 
989 	parse_early_param();
990 
991 	if (efi_enabled(EFI_BOOT))
992 		efi_memblock_x86_reserve_range();
993 
994 #ifdef CONFIG_MEMORY_HOTPLUG
995 	/*
996 	 * Memory used by the kernel cannot be hot-removed because Linux
997 	 * cannot migrate the kernel pages. When memory hotplug is
998 	 * enabled, we should prevent memblock from allocating memory
999 	 * for the kernel.
1000 	 *
1001 	 * ACPI SRAT records all hotpluggable memory ranges. But before
1002 	 * SRAT is parsed, we don't know about it.
1003 	 *
1004 	 * The kernel image is loaded into memory at very early time. We
1005 	 * cannot prevent this anyway. So on NUMA system, we set any
1006 	 * node the kernel resides in as un-hotpluggable.
1007 	 *
1008 	 * Since on modern servers, one node could have double-digit
1009 	 * gigabytes memory, we can assume the memory around the kernel
1010 	 * image is also un-hotpluggable. So before SRAT is parsed, just
1011 	 * allocate memory near the kernel image to try the best to keep
1012 	 * the kernel away from hotpluggable memory.
1013 	 */
1014 	if (movable_node_is_enabled())
1015 		memblock_set_bottom_up(true);
1016 #endif
1017 
1018 	x86_report_nx();
1019 
1020 	apic_setup_apic_calls();
1021 
1022 	if (acpi_mps_check()) {
1023 #ifdef CONFIG_X86_LOCAL_APIC
1024 		apic_is_disabled = true;
1025 #endif
1026 		setup_clear_cpu_cap(X86_FEATURE_APIC);
1027 	}
1028 
1029 	e820__reserve_setup_data();
1030 	e820__finish_early_params();
1031 
1032 	if (efi_enabled(EFI_BOOT))
1033 		efi_init();
1034 
1035 	reserve_ibft_region();
1036 	dmi_setup();
1037 
1038 	/*
1039 	 * VMware detection requires dmi to be available, so this
1040 	 * needs to be done after dmi_setup(), for the boot CPU.
1041 	 * For some guest types (Xen PV, SEV-SNP, TDX) it is required to be
1042 	 * called before cache_bp_init() for setting up MTRR state.
1043 	 */
1044 	init_hypervisor_platform();
1045 
1046 	tsc_early_init();
1047 	x86_init.resources.probe_roms();
1048 
1049 	/* after parse_early_param, so could debug it */
1050 	insert_resource(&iomem_resource, &code_resource);
1051 	insert_resource(&iomem_resource, &rodata_resource);
1052 	insert_resource(&iomem_resource, &data_resource);
1053 	insert_resource(&iomem_resource, &bss_resource);
1054 
1055 	e820_add_kernel_range();
1056 	trim_bios_range();
1057 #ifdef CONFIG_X86_32
1058 	if (ppro_with_ram_bug()) {
1059 		e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
1060 				  E820_TYPE_RESERVED);
1061 		e820__update_table(e820_table);
1062 		printk(KERN_INFO "fixed physical RAM map:\n");
1063 		e820__print_table("bad_ppro");
1064 	}
1065 #else
1066 	early_gart_iommu_check();
1067 #endif
1068 
1069 	/*
1070 	 * partially used pages are not usable - thus
1071 	 * we are rounding upwards:
1072 	 */
1073 	max_pfn = e820__end_of_ram_pfn();
1074 
1075 	/* update e820 for memory not covered by WB MTRRs */
1076 	cache_bp_init();
1077 	if (mtrr_trim_uncached_memory(max_pfn))
1078 		max_pfn = e820__end_of_ram_pfn();
1079 
1080 	max_possible_pfn = max_pfn;
1081 
1082 	/*
1083 	 * Define random base addresses for memory sections after max_pfn is
1084 	 * defined and before each memory section base is used.
1085 	 */
1086 	kernel_randomize_memory();
1087 
1088 #ifdef CONFIG_X86_32
1089 	/* max_low_pfn get updated here */
1090 	find_low_pfn_range();
1091 #else
1092 	check_x2apic();
1093 
1094 	/* How many end-of-memory variables you have, grandma! */
1095 	/* need this before calling reserve_initrd */
1096 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
1097 		max_low_pfn = e820__end_of_low_ram_pfn();
1098 	else
1099 		max_low_pfn = max_pfn;
1100 
1101 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1102 #endif
1103 
1104 	/*
1105 	 * Find and reserve possible boot-time SMP configuration:
1106 	 */
1107 	find_smp_config();
1108 
1109 	early_alloc_pgt_buf();
1110 
1111 	/*
1112 	 * Need to conclude brk, before e820__memblock_setup()
1113 	 * it could use memblock_find_in_range, could overlap with
1114 	 * brk area.
1115 	 */
1116 	reserve_brk();
1117 
1118 	cleanup_highmap();
1119 
1120 	memblock_set_current_limit(ISA_END_ADDRESS);
1121 	e820__memblock_setup();
1122 
1123 	/*
1124 	 * Needs to run after memblock setup because it needs the physical
1125 	 * memory size.
1126 	 */
1127 	sev_setup_arch();
1128 
1129 	efi_fake_memmap();
1130 	efi_find_mirror();
1131 	efi_esrt_init();
1132 	efi_mokvar_table_init();
1133 
1134 	/*
1135 	 * The EFI specification says that boot service code won't be
1136 	 * called after ExitBootServices(). This is, in fact, a lie.
1137 	 */
1138 	efi_reserve_boot_services();
1139 
1140 	/* preallocate 4k for mptable mpc */
1141 	e820__memblock_alloc_reserved_mpc_new();
1142 
1143 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1144 	setup_bios_corruption_check();
1145 #endif
1146 
1147 #ifdef CONFIG_X86_32
1148 	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1149 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1150 #endif
1151 
1152 	/*
1153 	 * Find free memory for the real mode trampoline and place it there. If
1154 	 * there is not enough free memory under 1M, on EFI-enabled systems
1155 	 * there will be additional attempt to reclaim the memory for the real
1156 	 * mode trampoline at efi_free_boot_services().
1157 	 *
1158 	 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1159 	 * are known to corrupt low memory and several hundred kilobytes are not
1160 	 * worth complex detection what memory gets clobbered. Windows does the
1161 	 * same thing for very similar reasons.
1162 	 *
1163 	 * Moreover, on machines with SandyBridge graphics or in setups that use
1164 	 * crashkernel the entire 1M is reserved anyway.
1165 	 */
1166 	x86_platform.realmode_reserve();
1167 
1168 	init_mem_mapping();
1169 
1170 	idt_setup_early_pf();
1171 
1172 	/*
1173 	 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1174 	 * with the current CR4 value.  This may not be necessary, but
1175 	 * auditing all the early-boot CR4 manipulation would be needed to
1176 	 * rule it out.
1177 	 *
1178 	 * Mask off features that don't work outside long mode (just
1179 	 * PCIDE for now).
1180 	 */
1181 	mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1182 
1183 	memblock_set_current_limit(get_max_mapped());
1184 
1185 	/*
1186 	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1187 	 */
1188 
1189 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1190 	if (init_ohci1394_dma_early)
1191 		init_ohci1394_dma_on_all_controllers();
1192 #endif
1193 	/* Allocate bigger log buffer */
1194 	setup_log_buf(1);
1195 
1196 	if (efi_enabled(EFI_BOOT)) {
1197 		switch (boot_params.secure_boot) {
1198 		case efi_secureboot_mode_disabled:
1199 			pr_info("Secure boot disabled\n");
1200 			break;
1201 		case efi_secureboot_mode_enabled:
1202 			pr_info("Secure boot enabled\n");
1203 			break;
1204 		default:
1205 			pr_info("Secure boot could not be determined\n");
1206 			break;
1207 		}
1208 	}
1209 
1210 	reserve_initrd();
1211 
1212 	acpi_table_upgrade();
1213 	/* Look for ACPI tables and reserve memory occupied by them. */
1214 	acpi_boot_table_init();
1215 
1216 	vsmp_init();
1217 
1218 	io_delay_init();
1219 
1220 	early_platform_quirks();
1221 
1222 	early_acpi_boot_init();
1223 
1224 	initmem_init();
1225 	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1226 
1227 	if (boot_cpu_has(X86_FEATURE_GBPAGES))
1228 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1229 
1230 	/*
1231 	 * Reserve memory for crash kernel after SRAT is parsed so that it
1232 	 * won't consume hotpluggable memory.
1233 	 */
1234 	reserve_crashkernel();
1235 
1236 	memblock_find_dma_reserve();
1237 
1238 	if (!early_xdbc_setup_hardware())
1239 		early_xdbc_register_console();
1240 
1241 	x86_init.paging.pagetable_init();
1242 
1243 	kasan_init();
1244 
1245 	/*
1246 	 * Sync back kernel address range.
1247 	 *
1248 	 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1249 	 * this call?
1250 	 */
1251 	sync_initial_page_table();
1252 
1253 	tboot_probe();
1254 
1255 	map_vsyscall();
1256 
1257 	x86_32_probe_apic();
1258 
1259 	early_quirks();
1260 
1261 	/*
1262 	 * Read APIC and some other early information from ACPI tables.
1263 	 */
1264 	acpi_boot_init();
1265 	x86_dtb_init();
1266 
1267 	/*
1268 	 * get boot-time SMP configuration:
1269 	 */
1270 	get_smp_config();
1271 
1272 	/*
1273 	 * Systems w/o ACPI and mptables might not have it mapped the local
1274 	 * APIC yet, but prefill_possible_map() might need to access it.
1275 	 */
1276 	init_apic_mappings();
1277 
1278 	prefill_possible_map();
1279 
1280 	init_cpu_to_node();
1281 	init_gi_nodes();
1282 
1283 	io_apic_init_mappings();
1284 
1285 	x86_init.hyper.guest_late_init();
1286 
1287 	e820__reserve_resources();
1288 	e820__register_nosave_regions(max_pfn);
1289 
1290 	x86_init.resources.reserve_resources();
1291 
1292 	e820__setup_pci_gap();
1293 
1294 #ifdef CONFIG_VT
1295 #if defined(CONFIG_VGA_CONSOLE)
1296 	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1297 		conswitchp = &vga_con;
1298 #endif
1299 #endif
1300 	x86_init.oem.banner();
1301 
1302 	x86_init.timers.wallclock_init();
1303 
1304 	/*
1305 	 * This needs to run before setup_local_APIC() which soft-disables the
1306 	 * local APIC temporarily and that masks the thermal LVT interrupt,
1307 	 * leading to softlockups on machines which have configured SMI
1308 	 * interrupt delivery.
1309 	 */
1310 	therm_lvt_init();
1311 
1312 	mcheck_init();
1313 
1314 	register_refined_jiffies(CLOCK_TICK_RATE);
1315 
1316 #ifdef CONFIG_EFI
1317 	if (efi_enabled(EFI_BOOT))
1318 		efi_apply_memmap_quirks();
1319 #endif
1320 
1321 	unwind_init();
1322 }
1323 
1324 #ifdef CONFIG_X86_32
1325 
1326 static struct resource video_ram_resource = {
1327 	.name	= "Video RAM area",
1328 	.start	= 0xa0000,
1329 	.end	= 0xbffff,
1330 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1331 };
1332 
1333 void __init i386_reserve_resources(void)
1334 {
1335 	request_resource(&iomem_resource, &video_ram_resource);
1336 	reserve_standard_io_resources();
1337 }
1338 
1339 #endif /* CONFIG_X86_32 */
1340 
1341 static struct notifier_block kernel_offset_notifier = {
1342 	.notifier_call = dump_kernel_offset
1343 };
1344 
1345 static int __init register_kernel_offset_dumper(void)
1346 {
1347 	atomic_notifier_chain_register(&panic_notifier_list,
1348 					&kernel_offset_notifier);
1349 	return 0;
1350 }
1351 __initcall(register_kernel_offset_dumper);
1352