xref: /linux/arch/x86/kernel/setup.c (revision 722ecdbce68a87de2d9296f91308f44ea900a039)
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/init_ohci1394_dma.h>
15 #include <linux/initrd.h>
16 #include <linux/iscsi_ibft.h>
17 #include <linux/memblock.h>
18 #include <linux/panic_notifier.h>
19 #include <linux/pci.h>
20 #include <linux/root_dev.h>
21 #include <linux/hugetlb.h>
22 #include <linux/tboot.h>
23 #include <linux/usb/xhci-dbgp.h>
24 #include <linux/static_call.h>
25 #include <linux/swiotlb.h>
26 
27 #include <uapi/linux/mount.h>
28 
29 #include <xen/xen.h>
30 
31 #include <asm/apic.h>
32 #include <asm/numa.h>
33 #include <asm/bios_ebda.h>
34 #include <asm/bugs.h>
35 #include <asm/cpu.h>
36 #include <asm/efi.h>
37 #include <asm/gart.h>
38 #include <asm/hypervisor.h>
39 #include <asm/io_apic.h>
40 #include <asm/kasan.h>
41 #include <asm/kaslr.h>
42 #include <asm/mce.h>
43 #include <asm/memtype.h>
44 #include <asm/mtrr.h>
45 #include <asm/realmode.h>
46 #include <asm/olpc_ofw.h>
47 #include <asm/pci-direct.h>
48 #include <asm/prom.h>
49 #include <asm/proto.h>
50 #include <asm/thermal.h>
51 #include <asm/unwind.h>
52 #include <asm/vsyscall.h>
53 #include <linux/vmalloc.h>
54 
55 /*
56  * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
57  * max_pfn_mapped:     highest directly mapped pfn > 4 GB
58  *
59  * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
60  * represented by pfn_mapped[].
61  */
62 unsigned long max_low_pfn_mapped;
63 unsigned long max_pfn_mapped;
64 
65 #ifdef CONFIG_DMI
66 RESERVE_BRK(dmi_alloc, 65536);
67 #endif
68 
69 
70 /*
71  * Range of the BSS area. The size of the BSS area is determined
72  * at link time, with RESERVE_BRK() facility reserving additional
73  * chunks.
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 /* Common CPU data for all CPUs */
120 struct cpuinfo_x86 boot_cpu_data __read_mostly;
121 EXPORT_SYMBOL(boot_cpu_data);
122 
123 unsigned int def_to_bigsmp;
124 
125 struct apm_info apm_info;
126 EXPORT_SYMBOL(apm_info);
127 
128 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
129 	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
130 struct ist_info ist_info;
131 EXPORT_SYMBOL(ist_info);
132 #else
133 struct ist_info ist_info;
134 #endif
135 
136 #else
137 struct cpuinfo_x86 boot_cpu_data __read_mostly;
138 EXPORT_SYMBOL(boot_cpu_data);
139 #endif
140 
141 
142 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
143 __visible unsigned long mmu_cr4_features __ro_after_init;
144 #else
145 __visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
146 #endif
147 
148 /* Boot loader ID and version as integers, for the benefit of proc_dointvec */
149 int bootloader_type, bootloader_version;
150 
151 /*
152  * Setup options
153  */
154 struct screen_info screen_info;
155 EXPORT_SYMBOL(screen_info);
156 struct edid_info edid_info;
157 EXPORT_SYMBOL_GPL(edid_info);
158 
159 extern int root_mountflags;
160 
161 unsigned long saved_video_mode;
162 
163 #define RAMDISK_IMAGE_START_MASK	0x07FF
164 #define RAMDISK_PROMPT_FLAG		0x8000
165 #define RAMDISK_LOAD_FLAG		0x4000
166 
167 static char __initdata command_line[COMMAND_LINE_SIZE];
168 #ifdef CONFIG_CMDLINE_BOOL
169 static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
170 #endif
171 
172 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
173 struct edd edd;
174 #ifdef CONFIG_EDD_MODULE
175 EXPORT_SYMBOL(edd);
176 #endif
177 /**
178  * copy_edd() - Copy the BIOS EDD information
179  *              from boot_params into a safe place.
180  *
181  */
182 static inline void __init copy_edd(void)
183 {
184      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
185 	    sizeof(edd.mbr_signature));
186      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
187      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
188      edd.edd_info_nr = boot_params.eddbuf_entries;
189 }
190 #else
191 static inline void __init copy_edd(void)
192 {
193 }
194 #endif
195 
196 void * __init extend_brk(size_t size, size_t align)
197 {
198 	size_t mask = align - 1;
199 	void *ret;
200 
201 	BUG_ON(_brk_start == 0);
202 	BUG_ON(align & mask);
203 
204 	_brk_end = (_brk_end + mask) & ~mask;
205 	BUG_ON((char *)(_brk_end + size) > __brk_limit);
206 
207 	ret = (void *)_brk_end;
208 	_brk_end += size;
209 
210 	memset(ret, 0, size);
211 
212 	return ret;
213 }
214 
215 #ifdef CONFIG_X86_32
216 static void __init cleanup_highmap(void)
217 {
218 }
219 #endif
220 
221 static void __init reserve_brk(void)
222 {
223 	if (_brk_end > _brk_start)
224 		memblock_reserve(__pa_symbol(_brk_start),
225 				 _brk_end - _brk_start);
226 
227 	/* Mark brk area as locked down and no longer taking any
228 	   new allocations */
229 	_brk_start = 0;
230 }
231 
232 u64 relocated_ramdisk;
233 
234 #ifdef CONFIG_BLK_DEV_INITRD
235 
236 static u64 __init get_ramdisk_image(void)
237 {
238 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
239 
240 	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
241 
242 	if (ramdisk_image == 0)
243 		ramdisk_image = phys_initrd_start;
244 
245 	return ramdisk_image;
246 }
247 static u64 __init get_ramdisk_size(void)
248 {
249 	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
250 
251 	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
252 
253 	if (ramdisk_size == 0)
254 		ramdisk_size = phys_initrd_size;
255 
256 	return ramdisk_size;
257 }
258 
259 static void __init relocate_initrd(void)
260 {
261 	/* Assume only end is not page aligned */
262 	u64 ramdisk_image = get_ramdisk_image();
263 	u64 ramdisk_size  = get_ramdisk_size();
264 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
265 
266 	/* We need to move the initrd down into directly mapped mem */
267 	relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
268 						      PFN_PHYS(max_pfn_mapped));
269 	if (!relocated_ramdisk)
270 		panic("Cannot find place for new RAMDISK of size %lld\n",
271 		      ramdisk_size);
272 
273 	initrd_start = relocated_ramdisk + PAGE_OFFSET;
274 	initrd_end   = initrd_start + ramdisk_size;
275 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
276 	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
277 
278 	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
279 
280 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
281 		" [mem %#010llx-%#010llx]\n",
282 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
283 		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
284 }
285 
286 static void __init early_reserve_initrd(void)
287 {
288 	/* Assume only end is not page aligned */
289 	u64 ramdisk_image = get_ramdisk_image();
290 	u64 ramdisk_size  = get_ramdisk_size();
291 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
292 
293 	if (!boot_params.hdr.type_of_loader ||
294 	    !ramdisk_image || !ramdisk_size)
295 		return;		/* No initrd provided by bootloader */
296 
297 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
298 }
299 
300 static void __init reserve_initrd(void)
301 {
302 	/* Assume only end is not page aligned */
303 	u64 ramdisk_image = get_ramdisk_image();
304 	u64 ramdisk_size  = get_ramdisk_size();
305 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
306 
307 	if (!boot_params.hdr.type_of_loader ||
308 	    !ramdisk_image || !ramdisk_size)
309 		return;		/* No initrd provided by bootloader */
310 
311 	initrd_start = 0;
312 
313 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
314 			ramdisk_end - 1);
315 
316 	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
317 				PFN_DOWN(ramdisk_end))) {
318 		/* All are mapped, easy case */
319 		initrd_start = ramdisk_image + PAGE_OFFSET;
320 		initrd_end = initrd_start + ramdisk_size;
321 		return;
322 	}
323 
324 	relocate_initrd();
325 
326 	memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image);
327 }
328 
329 #else
330 static void __init early_reserve_initrd(void)
331 {
332 }
333 static void __init reserve_initrd(void)
334 {
335 }
336 #endif /* CONFIG_BLK_DEV_INITRD */
337 
338 static void __init parse_setup_data(void)
339 {
340 	struct setup_data *data;
341 	u64 pa_data, pa_next;
342 
343 	pa_data = boot_params.hdr.setup_data;
344 	while (pa_data) {
345 		u32 data_len, data_type;
346 
347 		data = early_memremap(pa_data, sizeof(*data));
348 		data_len = data->len + sizeof(struct setup_data);
349 		data_type = data->type;
350 		pa_next = data->next;
351 		early_memunmap(data, sizeof(*data));
352 
353 		switch (data_type) {
354 		case SETUP_E820_EXT:
355 			e820__memory_setup_extended(pa_data, data_len);
356 			break;
357 		case SETUP_DTB:
358 			add_dtb(pa_data);
359 			break;
360 		case SETUP_EFI:
361 			parse_efi_setup(pa_data, data_len);
362 			break;
363 		default:
364 			break;
365 		}
366 		pa_data = pa_next;
367 	}
368 }
369 
370 static void __init memblock_x86_reserve_range_setup_data(void)
371 {
372 	struct setup_indirect *indirect;
373 	struct setup_data *data;
374 	u64 pa_data, pa_next;
375 	u32 len;
376 
377 	pa_data = boot_params.hdr.setup_data;
378 	while (pa_data) {
379 		data = early_memremap(pa_data, sizeof(*data));
380 		if (!data) {
381 			pr_warn("setup: failed to memremap setup_data entry\n");
382 			return;
383 		}
384 
385 		len = sizeof(*data);
386 		pa_next = data->next;
387 
388 		memblock_reserve(pa_data, sizeof(*data) + data->len);
389 
390 		if (data->type == SETUP_INDIRECT) {
391 			len += data->len;
392 			early_memunmap(data, sizeof(*data));
393 			data = early_memremap(pa_data, len);
394 			if (!data) {
395 				pr_warn("setup: failed to memremap indirect setup_data\n");
396 				return;
397 			}
398 
399 			indirect = (struct setup_indirect *)data->data;
400 
401 			if (indirect->type != SETUP_INDIRECT)
402 				memblock_reserve(indirect->addr, indirect->len);
403 		}
404 
405 		pa_data = pa_next;
406 		early_memunmap(data, len);
407 	}
408 }
409 
410 /*
411  * --------- Crashkernel reservation ------------------------------
412  */
413 
414 /* 16M alignment for crash kernel regions */
415 #define CRASH_ALIGN		SZ_16M
416 
417 /*
418  * Keep the crash kernel below this limit.
419  *
420  * Earlier 32-bits kernels would limit the kernel to the low 512 MB range
421  * due to mapping restrictions.
422  *
423  * 64-bit kdump kernels need to be restricted to be under 64 TB, which is
424  * the upper limit of system RAM in 4-level paging mode. Since the kdump
425  * jump could be from 5-level paging to 4-level paging, the jump will fail if
426  * the kernel is put above 64 TB, and during the 1st kernel bootup there's
427  * no good way to detect the paging mode of the target kernel which will be
428  * loaded for dumping.
429  */
430 #ifdef CONFIG_X86_32
431 # define CRASH_ADDR_LOW_MAX	SZ_512M
432 # define CRASH_ADDR_HIGH_MAX	SZ_512M
433 #else
434 # define CRASH_ADDR_LOW_MAX	SZ_4G
435 # define CRASH_ADDR_HIGH_MAX	SZ_64T
436 #endif
437 
438 static int __init reserve_crashkernel_low(void)
439 {
440 #ifdef CONFIG_X86_64
441 	unsigned long long base, low_base = 0, low_size = 0;
442 	unsigned long low_mem_limit;
443 	int ret;
444 
445 	low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
446 
447 	/* crashkernel=Y,low */
448 	ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base);
449 	if (ret) {
450 		/*
451 		 * two parts from kernel/dma/swiotlb.c:
452 		 * -swiotlb size: user-specified with swiotlb= or default.
453 		 *
454 		 * -swiotlb overflow buffer: now hardcoded to 32k. We round it
455 		 * to 8M for other buffers that may need to stay low too. Also
456 		 * make sure we allocate enough extra low memory so that we
457 		 * don't run out of DMA buffers for 32-bit devices.
458 		 */
459 		low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20);
460 	} else {
461 		/* passed with crashkernel=0,low ? */
462 		if (!low_size)
463 			return 0;
464 	}
465 
466 	low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
467 	if (!low_base) {
468 		pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
469 		       (unsigned long)(low_size >> 20));
470 		return -ENOMEM;
471 	}
472 
473 	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
474 		(unsigned long)(low_size >> 20),
475 		(unsigned long)(low_base >> 20),
476 		(unsigned long)(low_mem_limit >> 20));
477 
478 	crashk_low_res.start = low_base;
479 	crashk_low_res.end   = low_base + low_size - 1;
480 	insert_resource(&iomem_resource, &crashk_low_res);
481 #endif
482 	return 0;
483 }
484 
485 static void __init reserve_crashkernel(void)
486 {
487 	unsigned long long crash_size, crash_base, total_mem;
488 	bool high = false;
489 	int ret;
490 
491 	if (!IS_ENABLED(CONFIG_KEXEC_CORE))
492 		return;
493 
494 	total_mem = memblock_phys_mem_size();
495 
496 	/* crashkernel=XM */
497 	ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base);
498 	if (ret != 0 || crash_size <= 0) {
499 		/* crashkernel=X,high */
500 		ret = parse_crashkernel_high(boot_command_line, total_mem,
501 					     &crash_size, &crash_base);
502 		if (ret != 0 || crash_size <= 0)
503 			return;
504 		high = true;
505 	}
506 
507 	if (xen_pv_domain()) {
508 		pr_info("Ignoring crashkernel for a Xen PV domain\n");
509 		return;
510 	}
511 
512 	/* 0 means: find the address automatically */
513 	if (!crash_base) {
514 		/*
515 		 * Set CRASH_ADDR_LOW_MAX upper bound for crash memory,
516 		 * crashkernel=x,high reserves memory over 4G, also allocates
517 		 * 256M extra low memory for DMA buffers and swiotlb.
518 		 * But the extra memory is not required for all machines.
519 		 * So try low memory first and fall back to high memory
520 		 * unless "crashkernel=size[KMG],high" is specified.
521 		 */
522 		if (!high)
523 			crash_base = memblock_phys_alloc_range(crash_size,
524 						CRASH_ALIGN, CRASH_ALIGN,
525 						CRASH_ADDR_LOW_MAX);
526 		if (!crash_base)
527 			crash_base = memblock_phys_alloc_range(crash_size,
528 						CRASH_ALIGN, CRASH_ALIGN,
529 						CRASH_ADDR_HIGH_MAX);
530 		if (!crash_base) {
531 			pr_info("crashkernel reservation failed - No suitable area found.\n");
532 			return;
533 		}
534 	} else {
535 		unsigned long long start;
536 
537 		start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
538 						  crash_base + crash_size);
539 		if (start != crash_base) {
540 			pr_info("crashkernel reservation failed - memory is in use.\n");
541 			return;
542 		}
543 	}
544 
545 	if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
546 		memblock_phys_free(crash_base, crash_size);
547 		return;
548 	}
549 
550 	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
551 		(unsigned long)(crash_size >> 20),
552 		(unsigned long)(crash_base >> 20),
553 		(unsigned long)(total_mem >> 20));
554 
555 	crashk_res.start = crash_base;
556 	crashk_res.end   = crash_base + crash_size - 1;
557 	insert_resource(&iomem_resource, &crashk_res);
558 }
559 
560 static struct resource standard_io_resources[] = {
561 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
562 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
563 	{ .name = "pic1", .start = 0x20, .end = 0x21,
564 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
565 	{ .name = "timer0", .start = 0x40, .end = 0x43,
566 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
567 	{ .name = "timer1", .start = 0x50, .end = 0x53,
568 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
569 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
570 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
571 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
572 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
573 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
574 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
575 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
576 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
577 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
578 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
579 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
580 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
581 };
582 
583 void __init reserve_standard_io_resources(void)
584 {
585 	int i;
586 
587 	/* request I/O space for devices used on all i[345]86 PCs */
588 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
589 		request_resource(&ioport_resource, &standard_io_resources[i]);
590 
591 }
592 
593 static bool __init snb_gfx_workaround_needed(void)
594 {
595 #ifdef CONFIG_PCI
596 	int i;
597 	u16 vendor, devid;
598 	static const __initconst u16 snb_ids[] = {
599 		0x0102,
600 		0x0112,
601 		0x0122,
602 		0x0106,
603 		0x0116,
604 		0x0126,
605 		0x010a,
606 	};
607 
608 	/* Assume no if something weird is going on with PCI */
609 	if (!early_pci_allowed())
610 		return false;
611 
612 	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
613 	if (vendor != 0x8086)
614 		return false;
615 
616 	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
617 	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
618 		if (devid == snb_ids[i])
619 			return true;
620 #endif
621 
622 	return false;
623 }
624 
625 /*
626  * Sandy Bridge graphics has trouble with certain ranges, exclude
627  * them from allocation.
628  */
629 static void __init trim_snb_memory(void)
630 {
631 	static const __initconst unsigned long bad_pages[] = {
632 		0x20050000,
633 		0x20110000,
634 		0x20130000,
635 		0x20138000,
636 		0x40004000,
637 	};
638 	int i;
639 
640 	if (!snb_gfx_workaround_needed())
641 		return;
642 
643 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
644 
645 	/*
646 	 * SandyBridge integrated graphics devices have a bug that prevents
647 	 * them from accessing certain memory ranges, namely anything below
648 	 * 1M and in the pages listed in bad_pages[] above.
649 	 *
650 	 * To avoid these pages being ever accessed by SNB gfx devices reserve
651 	 * bad_pages that have not already been reserved at boot time.
652 	 * All memory below the 1 MB mark is anyway reserved later during
653 	 * setup_arch(), so there is no need to reserve it here.
654 	 */
655 
656 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
657 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
658 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
659 			       bad_pages[i]);
660 	}
661 }
662 
663 static void __init trim_bios_range(void)
664 {
665 	/*
666 	 * A special case is the first 4Kb of memory;
667 	 * This is a BIOS owned area, not kernel ram, but generally
668 	 * not listed as such in the E820 table.
669 	 *
670 	 * This typically reserves additional memory (64KiB by default)
671 	 * since some BIOSes are known to corrupt low memory.  See the
672 	 * Kconfig help text for X86_RESERVE_LOW.
673 	 */
674 	e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
675 
676 	/*
677 	 * special case: Some BIOSes report the PC BIOS
678 	 * area (640Kb -> 1Mb) as RAM even though it is not.
679 	 * take them out.
680 	 */
681 	e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
682 
683 	e820__update_table(e820_table);
684 }
685 
686 /* called before trim_bios_range() to spare extra sanitize */
687 static void __init e820_add_kernel_range(void)
688 {
689 	u64 start = __pa_symbol(_text);
690 	u64 size = __pa_symbol(_end) - start;
691 
692 	/*
693 	 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
694 	 * attempt to fix it by adding the range. We may have a confused BIOS,
695 	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
696 	 * exclude kernel range. If we really are running on top non-RAM,
697 	 * we will crash later anyways.
698 	 */
699 	if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
700 		return;
701 
702 	pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
703 	e820__range_remove(start, size, E820_TYPE_RAM, 0);
704 	e820__range_add(start, size, E820_TYPE_RAM);
705 }
706 
707 static void __init early_reserve_memory(void)
708 {
709 	/*
710 	 * Reserve the memory occupied by the kernel between _text and
711 	 * __end_of_kernel_reserve symbols. Any kernel sections after the
712 	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
713 	 * separate memblock_reserve() or they will be discarded.
714 	 */
715 	memblock_reserve(__pa_symbol(_text),
716 			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
717 
718 	/*
719 	 * The first 4Kb of memory is a BIOS owned area, but generally it is
720 	 * not listed as such in the E820 table.
721 	 *
722 	 * Reserve the first 64K of memory since some BIOSes are known to
723 	 * corrupt low memory. After the real mode trampoline is allocated the
724 	 * rest of the memory below 640k is reserved.
725 	 *
726 	 * In addition, make sure page 0 is always reserved because on
727 	 * systems with L1TF its contents can be leaked to user processes.
728 	 */
729 	memblock_reserve(0, SZ_64K);
730 
731 	early_reserve_initrd();
732 
733 	memblock_x86_reserve_range_setup_data();
734 
735 	reserve_ibft_region();
736 	reserve_bios_regions();
737 	trim_snb_memory();
738 }
739 
740 /*
741  * Dump out kernel offset information on panic.
742  */
743 static int
744 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
745 {
746 	if (kaslr_enabled()) {
747 		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
748 			 kaslr_offset(),
749 			 __START_KERNEL,
750 			 __START_KERNEL_map,
751 			 MODULES_VADDR-1);
752 	} else {
753 		pr_emerg("Kernel Offset: disabled\n");
754 	}
755 
756 	return 0;
757 }
758 
759 void x86_configure_nx(void)
760 {
761 	if (boot_cpu_has(X86_FEATURE_NX))
762 		__supported_pte_mask |= _PAGE_NX;
763 	else
764 		__supported_pte_mask &= ~_PAGE_NX;
765 }
766 
767 static void __init x86_report_nx(void)
768 {
769 	if (!boot_cpu_has(X86_FEATURE_NX)) {
770 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
771 		       "missing in CPU!\n");
772 	} else {
773 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
774 		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
775 #else
776 		/* 32bit non-PAE kernel, NX cannot be used */
777 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
778 		       "cannot be enabled: non-PAE kernel!\n");
779 #endif
780 	}
781 }
782 
783 /*
784  * Determine if we were loaded by an EFI loader.  If so, then we have also been
785  * passed the efi memmap, systab, etc., so we should use these data structures
786  * for initialization.  Note, the efi init code path is determined by the
787  * global efi_enabled. This allows the same kernel image to be used on existing
788  * systems (with a traditional BIOS) as well as on EFI systems.
789  */
790 /*
791  * setup_arch - architecture-specific boot-time initializations
792  *
793  * Note: On x86_64, fixmaps are ready for use even before this is called.
794  */
795 
796 void __init setup_arch(char **cmdline_p)
797 {
798 #ifdef CONFIG_X86_32
799 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
800 
801 	/*
802 	 * copy kernel address range established so far and switch
803 	 * to the proper swapper page table
804 	 */
805 	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
806 			initial_page_table + KERNEL_PGD_BOUNDARY,
807 			KERNEL_PGD_PTRS);
808 
809 	load_cr3(swapper_pg_dir);
810 	/*
811 	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
812 	 * a cr3 based tlb flush, so the following __flush_tlb_all()
813 	 * will not flush anything because the CPU quirk which clears
814 	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
815 	 * load_cr3() above the TLB has been flushed already. The
816 	 * quirk is invoked before subsequent calls to __flush_tlb_all()
817 	 * so proper operation is guaranteed.
818 	 */
819 	__flush_tlb_all();
820 #else
821 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
822 	boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
823 #endif
824 
825 	/*
826 	 * If we have OLPC OFW, we might end up relocating the fixmap due to
827 	 * reserve_top(), so do this before touching the ioremap area.
828 	 */
829 	olpc_ofw_detect();
830 
831 	idt_setup_early_traps();
832 	early_cpu_init();
833 	jump_label_init();
834 	static_call_init();
835 	early_ioremap_init();
836 
837 	setup_olpc_ofw_pgd();
838 
839 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
840 	screen_info = boot_params.screen_info;
841 	edid_info = boot_params.edid_info;
842 #ifdef CONFIG_X86_32
843 	apm_info.bios = boot_params.apm_bios_info;
844 	ist_info = boot_params.ist_info;
845 #endif
846 	saved_video_mode = boot_params.hdr.vid_mode;
847 	bootloader_type = boot_params.hdr.type_of_loader;
848 	if ((bootloader_type >> 4) == 0xe) {
849 		bootloader_type &= 0xf;
850 		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
851 	}
852 	bootloader_version  = bootloader_type & 0xf;
853 	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
854 
855 #ifdef CONFIG_BLK_DEV_RAM
856 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
857 #endif
858 #ifdef CONFIG_EFI
859 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
860 		     EFI32_LOADER_SIGNATURE, 4)) {
861 		set_bit(EFI_BOOT, &efi.flags);
862 	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
863 		     EFI64_LOADER_SIGNATURE, 4)) {
864 		set_bit(EFI_BOOT, &efi.flags);
865 		set_bit(EFI_64BIT, &efi.flags);
866 	}
867 #endif
868 
869 	x86_init.oem.arch_setup();
870 
871 	/*
872 	 * Do some memory reservations *before* memory is added to memblock, so
873 	 * memblock allocations won't overwrite it.
874 	 *
875 	 * After this point, everything still needed from the boot loader or
876 	 * firmware or kernel text should be early reserved or marked not RAM in
877 	 * e820. All other memory is free game.
878 	 *
879 	 * This call needs to happen before e820__memory_setup() which calls the
880 	 * xen_memory_setup() on Xen dom0 which relies on the fact that those
881 	 * early reservations have happened already.
882 	 */
883 	early_reserve_memory();
884 
885 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
886 	e820__memory_setup();
887 	parse_setup_data();
888 
889 	copy_edd();
890 
891 	if (!boot_params.hdr.root_flags)
892 		root_mountflags &= ~MS_RDONLY;
893 	setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
894 
895 	code_resource.start = __pa_symbol(_text);
896 	code_resource.end = __pa_symbol(_etext)-1;
897 	rodata_resource.start = __pa_symbol(__start_rodata);
898 	rodata_resource.end = __pa_symbol(__end_rodata)-1;
899 	data_resource.start = __pa_symbol(_sdata);
900 	data_resource.end = __pa_symbol(_edata)-1;
901 	bss_resource.start = __pa_symbol(__bss_start);
902 	bss_resource.end = __pa_symbol(__bss_stop)-1;
903 
904 #ifdef CONFIG_CMDLINE_BOOL
905 #ifdef CONFIG_CMDLINE_OVERRIDE
906 	strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
907 #else
908 	if (builtin_cmdline[0]) {
909 		/* append boot loader cmdline to builtin */
910 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
911 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
912 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
913 	}
914 #endif
915 #endif
916 
917 	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
918 	*cmdline_p = command_line;
919 
920 	/*
921 	 * x86_configure_nx() is called before parse_early_param() to detect
922 	 * whether hardware doesn't support NX (so that the early EHCI debug
923 	 * console setup can safely call set_fixmap()).
924 	 */
925 	x86_configure_nx();
926 
927 	parse_early_param();
928 
929 	if (efi_enabled(EFI_BOOT))
930 		efi_memblock_x86_reserve_range();
931 
932 #ifdef CONFIG_MEMORY_HOTPLUG
933 	/*
934 	 * Memory used by the kernel cannot be hot-removed because Linux
935 	 * cannot migrate the kernel pages. When memory hotplug is
936 	 * enabled, we should prevent memblock from allocating memory
937 	 * for the kernel.
938 	 *
939 	 * ACPI SRAT records all hotpluggable memory ranges. But before
940 	 * SRAT is parsed, we don't know about it.
941 	 *
942 	 * The kernel image is loaded into memory at very early time. We
943 	 * cannot prevent this anyway. So on NUMA system, we set any
944 	 * node the kernel resides in as un-hotpluggable.
945 	 *
946 	 * Since on modern servers, one node could have double-digit
947 	 * gigabytes memory, we can assume the memory around the kernel
948 	 * image is also un-hotpluggable. So before SRAT is parsed, just
949 	 * allocate memory near the kernel image to try the best to keep
950 	 * the kernel away from hotpluggable memory.
951 	 */
952 	if (movable_node_is_enabled())
953 		memblock_set_bottom_up(true);
954 #endif
955 
956 	x86_report_nx();
957 
958 	if (acpi_mps_check()) {
959 #ifdef CONFIG_X86_LOCAL_APIC
960 		disable_apic = 1;
961 #endif
962 		setup_clear_cpu_cap(X86_FEATURE_APIC);
963 	}
964 
965 	e820__reserve_setup_data();
966 	e820__finish_early_params();
967 
968 	if (efi_enabled(EFI_BOOT))
969 		efi_init();
970 
971 	dmi_setup();
972 
973 	/*
974 	 * VMware detection requires dmi to be available, so this
975 	 * needs to be done after dmi_setup(), for the boot CPU.
976 	 */
977 	init_hypervisor_platform();
978 
979 	tsc_early_init();
980 	x86_init.resources.probe_roms();
981 
982 	/* after parse_early_param, so could debug it */
983 	insert_resource(&iomem_resource, &code_resource);
984 	insert_resource(&iomem_resource, &rodata_resource);
985 	insert_resource(&iomem_resource, &data_resource);
986 	insert_resource(&iomem_resource, &bss_resource);
987 
988 	e820_add_kernel_range();
989 	trim_bios_range();
990 #ifdef CONFIG_X86_32
991 	if (ppro_with_ram_bug()) {
992 		e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
993 				  E820_TYPE_RESERVED);
994 		e820__update_table(e820_table);
995 		printk(KERN_INFO "fixed physical RAM map:\n");
996 		e820__print_table("bad_ppro");
997 	}
998 #else
999 	early_gart_iommu_check();
1000 #endif
1001 
1002 	/*
1003 	 * partially used pages are not usable - thus
1004 	 * we are rounding upwards:
1005 	 */
1006 	max_pfn = e820__end_of_ram_pfn();
1007 
1008 	/* update e820 for memory not covered by WB MTRRs */
1009 	if (IS_ENABLED(CONFIG_MTRR))
1010 		mtrr_bp_init();
1011 	else
1012 		pat_disable("PAT support disabled because CONFIG_MTRR is disabled in the kernel.");
1013 
1014 	if (mtrr_trim_uncached_memory(max_pfn))
1015 		max_pfn = e820__end_of_ram_pfn();
1016 
1017 	max_possible_pfn = max_pfn;
1018 
1019 	/*
1020 	 * This call is required when the CPU does not support PAT. If
1021 	 * mtrr_bp_init() invoked it already via pat_init() the call has no
1022 	 * effect.
1023 	 */
1024 	init_cache_modes();
1025 
1026 	/*
1027 	 * Define random base addresses for memory sections after max_pfn is
1028 	 * defined and before each memory section base is used.
1029 	 */
1030 	kernel_randomize_memory();
1031 
1032 #ifdef CONFIG_X86_32
1033 	/* max_low_pfn get updated here */
1034 	find_low_pfn_range();
1035 #else
1036 	check_x2apic();
1037 
1038 	/* How many end-of-memory variables you have, grandma! */
1039 	/* need this before calling reserve_initrd */
1040 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
1041 		max_low_pfn = e820__end_of_low_ram_pfn();
1042 	else
1043 		max_low_pfn = max_pfn;
1044 
1045 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1046 #endif
1047 
1048 	/*
1049 	 * Find and reserve possible boot-time SMP configuration:
1050 	 */
1051 	find_smp_config();
1052 
1053 	early_alloc_pgt_buf();
1054 
1055 	/*
1056 	 * Need to conclude brk, before e820__memblock_setup()
1057 	 * it could use memblock_find_in_range, could overlap with
1058 	 * brk area.
1059 	 */
1060 	reserve_brk();
1061 
1062 	cleanup_highmap();
1063 
1064 	memblock_set_current_limit(ISA_END_ADDRESS);
1065 	e820__memblock_setup();
1066 
1067 	/*
1068 	 * Needs to run after memblock setup because it needs the physical
1069 	 * memory size.
1070 	 */
1071 	sev_setup_arch();
1072 
1073 	efi_fake_memmap();
1074 	efi_find_mirror();
1075 	efi_esrt_init();
1076 	efi_mokvar_table_init();
1077 
1078 	/*
1079 	 * The EFI specification says that boot service code won't be
1080 	 * called after ExitBootServices(). This is, in fact, a lie.
1081 	 */
1082 	efi_reserve_boot_services();
1083 
1084 	/* preallocate 4k for mptable mpc */
1085 	e820__memblock_alloc_reserved_mpc_new();
1086 
1087 #ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1088 	setup_bios_corruption_check();
1089 #endif
1090 
1091 #ifdef CONFIG_X86_32
1092 	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1093 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1094 #endif
1095 
1096 	/*
1097 	 * Find free memory for the real mode trampoline and place it there. If
1098 	 * there is not enough free memory under 1M, on EFI-enabled systems
1099 	 * there will be additional attempt to reclaim the memory for the real
1100 	 * mode trampoline at efi_free_boot_services().
1101 	 *
1102 	 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1103 	 * are known to corrupt low memory and several hundred kilobytes are not
1104 	 * worth complex detection what memory gets clobbered. Windows does the
1105 	 * same thing for very similar reasons.
1106 	 *
1107 	 * Moreover, on machines with SandyBridge graphics or in setups that use
1108 	 * crashkernel the entire 1M is reserved anyway.
1109 	 */
1110 	reserve_real_mode();
1111 
1112 	init_mem_mapping();
1113 
1114 	idt_setup_early_pf();
1115 
1116 	/*
1117 	 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1118 	 * with the current CR4 value.  This may not be necessary, but
1119 	 * auditing all the early-boot CR4 manipulation would be needed to
1120 	 * rule it out.
1121 	 *
1122 	 * Mask off features that don't work outside long mode (just
1123 	 * PCIDE for now).
1124 	 */
1125 	mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1126 
1127 	memblock_set_current_limit(get_max_mapped());
1128 
1129 	/*
1130 	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1131 	 */
1132 
1133 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1134 	if (init_ohci1394_dma_early)
1135 		init_ohci1394_dma_on_all_controllers();
1136 #endif
1137 	/* Allocate bigger log buffer */
1138 	setup_log_buf(1);
1139 
1140 	if (efi_enabled(EFI_BOOT)) {
1141 		switch (boot_params.secure_boot) {
1142 		case efi_secureboot_mode_disabled:
1143 			pr_info("Secure boot disabled\n");
1144 			break;
1145 		case efi_secureboot_mode_enabled:
1146 			pr_info("Secure boot enabled\n");
1147 			break;
1148 		default:
1149 			pr_info("Secure boot could not be determined\n");
1150 			break;
1151 		}
1152 	}
1153 
1154 	reserve_initrd();
1155 
1156 	acpi_table_upgrade();
1157 	/* Look for ACPI tables and reserve memory occupied by them. */
1158 	acpi_boot_table_init();
1159 
1160 	vsmp_init();
1161 
1162 	io_delay_init();
1163 
1164 	early_platform_quirks();
1165 
1166 	early_acpi_boot_init();
1167 
1168 	initmem_init();
1169 	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1170 
1171 	if (boot_cpu_has(X86_FEATURE_GBPAGES))
1172 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1173 
1174 	/*
1175 	 * Reserve memory for crash kernel after SRAT is parsed so that it
1176 	 * won't consume hotpluggable memory.
1177 	 */
1178 	reserve_crashkernel();
1179 
1180 	memblock_find_dma_reserve();
1181 
1182 	if (!early_xdbc_setup_hardware())
1183 		early_xdbc_register_console();
1184 
1185 	x86_init.paging.pagetable_init();
1186 
1187 	kasan_init();
1188 
1189 	/*
1190 	 * Sync back kernel address range.
1191 	 *
1192 	 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1193 	 * this call?
1194 	 */
1195 	sync_initial_page_table();
1196 
1197 	tboot_probe();
1198 
1199 	map_vsyscall();
1200 
1201 	generic_apic_probe();
1202 
1203 	early_quirks();
1204 
1205 	/*
1206 	 * Read APIC and some other early information from ACPI tables.
1207 	 */
1208 	acpi_boot_init();
1209 	x86_dtb_init();
1210 
1211 	/*
1212 	 * get boot-time SMP configuration:
1213 	 */
1214 	get_smp_config();
1215 
1216 	/*
1217 	 * Systems w/o ACPI and mptables might not have it mapped the local
1218 	 * APIC yet, but prefill_possible_map() might need to access it.
1219 	 */
1220 	init_apic_mappings();
1221 
1222 	prefill_possible_map();
1223 
1224 	init_cpu_to_node();
1225 	init_gi_nodes();
1226 
1227 	io_apic_init_mappings();
1228 
1229 	x86_init.hyper.guest_late_init();
1230 
1231 	e820__reserve_resources();
1232 	e820__register_nosave_regions(max_pfn);
1233 
1234 	x86_init.resources.reserve_resources();
1235 
1236 	e820__setup_pci_gap();
1237 
1238 #ifdef CONFIG_VT
1239 #if defined(CONFIG_VGA_CONSOLE)
1240 	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1241 		conswitchp = &vga_con;
1242 #endif
1243 #endif
1244 	x86_init.oem.banner();
1245 
1246 	x86_init.timers.wallclock_init();
1247 
1248 	/*
1249 	 * This needs to run before setup_local_APIC() which soft-disables the
1250 	 * local APIC temporarily and that masks the thermal LVT interrupt,
1251 	 * leading to softlockups on machines which have configured SMI
1252 	 * interrupt delivery.
1253 	 */
1254 	therm_lvt_init();
1255 
1256 	mcheck_init();
1257 
1258 	register_refined_jiffies(CLOCK_TICK_RATE);
1259 
1260 #ifdef CONFIG_EFI
1261 	if (efi_enabled(EFI_BOOT))
1262 		efi_apply_memmap_quirks();
1263 #endif
1264 
1265 	unwind_init();
1266 }
1267 
1268 #ifdef CONFIG_X86_32
1269 
1270 static struct resource video_ram_resource = {
1271 	.name	= "Video RAM area",
1272 	.start	= 0xa0000,
1273 	.end	= 0xbffff,
1274 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1275 };
1276 
1277 void __init i386_reserve_resources(void)
1278 {
1279 	request_resource(&iomem_resource, &video_ram_resource);
1280 	reserve_standard_io_resources();
1281 }
1282 
1283 #endif /* CONFIG_X86_32 */
1284 
1285 static struct notifier_block kernel_offset_notifier = {
1286 	.notifier_call = dump_kernel_offset
1287 };
1288 
1289 static int __init register_kernel_offset_dumper(void)
1290 {
1291 	atomic_notifier_chain_register(&panic_notifier_list,
1292 					&kernel_offset_notifier);
1293 	return 0;
1294 }
1295 __initcall(register_kernel_offset_dumper);
1296