xref: /linux/arch/x86/kernel/setup.c (revision 257ca10c7317d4a424e48bb95d14ca53a1f1dd6f)
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 #ifdef CONFIG_BLK_DEV_INITRD
230 
231 static u64 __init get_ramdisk_image(void)
232 {
233 	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
234 
235 	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
236 
237 	if (ramdisk_image == 0)
238 		ramdisk_image = phys_initrd_start;
239 
240 	return ramdisk_image;
241 }
242 static u64 __init get_ramdisk_size(void)
243 {
244 	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
245 
246 	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
247 
248 	if (ramdisk_size == 0)
249 		ramdisk_size = phys_initrd_size;
250 
251 	return ramdisk_size;
252 }
253 
254 static void __init relocate_initrd(void)
255 {
256 	/* Assume only end is not page aligned */
257 	u64 ramdisk_image = get_ramdisk_image();
258 	u64 ramdisk_size  = get_ramdisk_size();
259 	u64 area_size     = PAGE_ALIGN(ramdisk_size);
260 
261 	/* We need to move the initrd down into directly mapped mem */
262 	u64 relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
263 						      PFN_PHYS(max_pfn_mapped));
264 	if (!relocated_ramdisk)
265 		panic("Cannot find place for new RAMDISK of size %lld\n",
266 		      ramdisk_size);
267 
268 	initrd_start = relocated_ramdisk + PAGE_OFFSET;
269 	initrd_end   = initrd_start + ramdisk_size;
270 	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
271 	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
272 
273 	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
274 
275 	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
276 		" [mem %#010llx-%#010llx]\n",
277 		ramdisk_image, ramdisk_image + ramdisk_size - 1,
278 		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
279 }
280 
281 static void __init early_reserve_initrd(void)
282 {
283 	/* Assume only end is not page aligned */
284 	u64 ramdisk_image = get_ramdisk_image();
285 	u64 ramdisk_size  = get_ramdisk_size();
286 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
287 
288 	if (!boot_params.hdr.type_of_loader ||
289 	    !ramdisk_image || !ramdisk_size)
290 		return;		/* No initrd provided by bootloader */
291 
292 	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
293 }
294 
295 static void __init reserve_initrd(void)
296 {
297 	/* Assume only end is not page aligned */
298 	u64 ramdisk_image = get_ramdisk_image();
299 	u64 ramdisk_size  = get_ramdisk_size();
300 	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
301 
302 	if (!boot_params.hdr.type_of_loader ||
303 	    !ramdisk_image || !ramdisk_size)
304 		return;		/* No initrd provided by bootloader */
305 
306 	initrd_start = 0;
307 
308 	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
309 			ramdisk_end - 1);
310 
311 	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
312 				PFN_DOWN(ramdisk_end))) {
313 		/* All are mapped, easy case */
314 		initrd_start = ramdisk_image + PAGE_OFFSET;
315 		initrd_end = initrd_start + ramdisk_size;
316 		return;
317 	}
318 
319 	relocate_initrd();
320 
321 	memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image);
322 }
323 
324 #else
325 static void __init early_reserve_initrd(void)
326 {
327 }
328 static void __init reserve_initrd(void)
329 {
330 }
331 #endif /* CONFIG_BLK_DEV_INITRD */
332 
333 static void __init add_early_ima_buffer(u64 phys_addr)
334 {
335 #ifdef CONFIG_IMA
336 	struct ima_setup_data *data;
337 
338 	data = early_memremap(phys_addr + sizeof(struct setup_data), sizeof(*data));
339 	if (!data) {
340 		pr_warn("setup: failed to memremap ima_setup_data entry\n");
341 		return;
342 	}
343 
344 	if (data->size) {
345 		memblock_reserve(data->addr, data->size);
346 		ima_kexec_buffer_phys = data->addr;
347 		ima_kexec_buffer_size = data->size;
348 	}
349 
350 	early_memunmap(data, sizeof(*data));
351 #else
352 	pr_warn("Passed IMA kexec data, but CONFIG_IMA not set. Ignoring.\n");
353 #endif
354 }
355 
356 #if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE)
357 int __init ima_free_kexec_buffer(void)
358 {
359 	if (!ima_kexec_buffer_size)
360 		return -ENOENT;
361 
362 	memblock_free_late(ima_kexec_buffer_phys,
363 			   ima_kexec_buffer_size);
364 
365 	ima_kexec_buffer_phys = 0;
366 	ima_kexec_buffer_size = 0;
367 
368 	return 0;
369 }
370 
371 int __init ima_get_kexec_buffer(void **addr, size_t *size)
372 {
373 	if (!ima_kexec_buffer_size)
374 		return -ENOENT;
375 
376 	*addr = __va(ima_kexec_buffer_phys);
377 	*size = ima_kexec_buffer_size;
378 
379 	return 0;
380 }
381 #endif
382 
383 static void __init parse_setup_data(void)
384 {
385 	struct setup_data *data;
386 	u64 pa_data, pa_next;
387 
388 	pa_data = boot_params.hdr.setup_data;
389 	while (pa_data) {
390 		u32 data_len, data_type;
391 
392 		data = early_memremap(pa_data, sizeof(*data));
393 		data_len = data->len + sizeof(struct setup_data);
394 		data_type = data->type;
395 		pa_next = data->next;
396 		early_memunmap(data, sizeof(*data));
397 
398 		switch (data_type) {
399 		case SETUP_E820_EXT:
400 			e820__memory_setup_extended(pa_data, data_len);
401 			break;
402 		case SETUP_DTB:
403 			add_dtb(pa_data);
404 			break;
405 		case SETUP_EFI:
406 			parse_efi_setup(pa_data, data_len);
407 			break;
408 		case SETUP_IMA:
409 			add_early_ima_buffer(pa_data);
410 			break;
411 		case SETUP_RNG_SEED:
412 			data = early_memremap(pa_data, data_len);
413 			add_bootloader_randomness(data->data, data->len);
414 			/* Zero seed for forward secrecy. */
415 			memzero_explicit(data->data, data->len);
416 			/* Zero length in case we find ourselves back here by accident. */
417 			memzero_explicit(&data->len, sizeof(data->len));
418 			early_memunmap(data, data_len);
419 			break;
420 		default:
421 			break;
422 		}
423 		pa_data = pa_next;
424 	}
425 }
426 
427 static void __init memblock_x86_reserve_range_setup_data(void)
428 {
429 	struct setup_indirect *indirect;
430 	struct setup_data *data;
431 	u64 pa_data, pa_next;
432 	u32 len;
433 
434 	pa_data = boot_params.hdr.setup_data;
435 	while (pa_data) {
436 		data = early_memremap(pa_data, sizeof(*data));
437 		if (!data) {
438 			pr_warn("setup: failed to memremap setup_data entry\n");
439 			return;
440 		}
441 
442 		len = sizeof(*data);
443 		pa_next = data->next;
444 
445 		memblock_reserve(pa_data, sizeof(*data) + data->len);
446 
447 		if (data->type == SETUP_INDIRECT) {
448 			len += data->len;
449 			early_memunmap(data, sizeof(*data));
450 			data = early_memremap(pa_data, len);
451 			if (!data) {
452 				pr_warn("setup: failed to memremap indirect setup_data\n");
453 				return;
454 			}
455 
456 			indirect = (struct setup_indirect *)data->data;
457 
458 			if (indirect->type != SETUP_INDIRECT)
459 				memblock_reserve(indirect->addr, indirect->len);
460 		}
461 
462 		pa_data = pa_next;
463 		early_memunmap(data, len);
464 	}
465 }
466 
467 static void __init arch_reserve_crashkernel(void)
468 {
469 	unsigned long long crash_base, crash_size, low_size = 0;
470 	char *cmdline = boot_command_line;
471 	bool high = false;
472 	int ret;
473 
474 	if (!IS_ENABLED(CONFIG_KEXEC_CORE))
475 		return;
476 
477 	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
478 				&crash_size, &crash_base,
479 				&low_size, &high);
480 	if (ret)
481 		return;
482 
483 	if (xen_pv_domain()) {
484 		pr_info("Ignoring crashkernel for a Xen PV domain\n");
485 		return;
486 	}
487 
488 	reserve_crashkernel_generic(cmdline, crash_size, crash_base,
489 				    low_size, high);
490 }
491 
492 static struct resource standard_io_resources[] = {
493 	{ .name = "dma1", .start = 0x00, .end = 0x1f,
494 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
495 	{ .name = "pic1", .start = 0x20, .end = 0x21,
496 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
497 	{ .name = "timer0", .start = 0x40, .end = 0x43,
498 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
499 	{ .name = "timer1", .start = 0x50, .end = 0x53,
500 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
501 	{ .name = "keyboard", .start = 0x60, .end = 0x60,
502 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
503 	{ .name = "keyboard", .start = 0x64, .end = 0x64,
504 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
505 	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
506 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
507 	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
508 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
509 	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
510 		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
511 	{ .name = "fpu", .start = 0xf0, .end = 0xff,
512 		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
513 };
514 
515 void __init reserve_standard_io_resources(void)
516 {
517 	int i;
518 
519 	/* request I/O space for devices used on all i[345]86 PCs */
520 	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
521 		request_resource(&ioport_resource, &standard_io_resources[i]);
522 
523 }
524 
525 static bool __init snb_gfx_workaround_needed(void)
526 {
527 #ifdef CONFIG_PCI
528 	int i;
529 	u16 vendor, devid;
530 	static const __initconst u16 snb_ids[] = {
531 		0x0102,
532 		0x0112,
533 		0x0122,
534 		0x0106,
535 		0x0116,
536 		0x0126,
537 		0x010a,
538 	};
539 
540 	/* Assume no if something weird is going on with PCI */
541 	if (!early_pci_allowed())
542 		return false;
543 
544 	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
545 	if (vendor != 0x8086)
546 		return false;
547 
548 	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
549 	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
550 		if (devid == snb_ids[i])
551 			return true;
552 #endif
553 
554 	return false;
555 }
556 
557 /*
558  * Sandy Bridge graphics has trouble with certain ranges, exclude
559  * them from allocation.
560  */
561 static void __init trim_snb_memory(void)
562 {
563 	static const __initconst unsigned long bad_pages[] = {
564 		0x20050000,
565 		0x20110000,
566 		0x20130000,
567 		0x20138000,
568 		0x40004000,
569 	};
570 	int i;
571 
572 	if (!snb_gfx_workaround_needed())
573 		return;
574 
575 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
576 
577 	/*
578 	 * SandyBridge integrated graphics devices have a bug that prevents
579 	 * them from accessing certain memory ranges, namely anything below
580 	 * 1M and in the pages listed in bad_pages[] above.
581 	 *
582 	 * To avoid these pages being ever accessed by SNB gfx devices reserve
583 	 * bad_pages that have not already been reserved at boot time.
584 	 * All memory below the 1 MB mark is anyway reserved later during
585 	 * setup_arch(), so there is no need to reserve it here.
586 	 */
587 
588 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
589 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
590 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
591 			       bad_pages[i]);
592 	}
593 }
594 
595 static void __init trim_bios_range(void)
596 {
597 	/*
598 	 * A special case is the first 4Kb of memory;
599 	 * This is a BIOS owned area, not kernel ram, but generally
600 	 * not listed as such in the E820 table.
601 	 *
602 	 * This typically reserves additional memory (64KiB by default)
603 	 * since some BIOSes are known to corrupt low memory.  See the
604 	 * Kconfig help text for X86_RESERVE_LOW.
605 	 */
606 	e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
607 
608 	/*
609 	 * special case: Some BIOSes report the PC BIOS
610 	 * area (640Kb -> 1Mb) as RAM even though it is not.
611 	 * take them out.
612 	 */
613 	e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
614 
615 	e820__update_table(e820_table);
616 }
617 
618 /* called before trim_bios_range() to spare extra sanitize */
619 static void __init e820_add_kernel_range(void)
620 {
621 	u64 start = __pa_symbol(_text);
622 	u64 size = __pa_symbol(_end) - start;
623 
624 	/*
625 	 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
626 	 * attempt to fix it by adding the range. We may have a confused BIOS,
627 	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
628 	 * exclude kernel range. If we really are running on top non-RAM,
629 	 * we will crash later anyways.
630 	 */
631 	if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
632 		return;
633 
634 	pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
635 	e820__range_remove(start, size, E820_TYPE_RAM, 0);
636 	e820__range_add(start, size, E820_TYPE_RAM);
637 }
638 
639 static void __init early_reserve_memory(void)
640 {
641 	/*
642 	 * Reserve the memory occupied by the kernel between _text and
643 	 * __end_of_kernel_reserve symbols. Any kernel sections after the
644 	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
645 	 * separate memblock_reserve() or they will be discarded.
646 	 */
647 	memblock_reserve(__pa_symbol(_text),
648 			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
649 
650 	/*
651 	 * The first 4Kb of memory is a BIOS owned area, but generally it is
652 	 * not listed as such in the E820 table.
653 	 *
654 	 * Reserve the first 64K of memory since some BIOSes are known to
655 	 * corrupt low memory. After the real mode trampoline is allocated the
656 	 * rest of the memory below 640k is reserved.
657 	 *
658 	 * In addition, make sure page 0 is always reserved because on
659 	 * systems with L1TF its contents can be leaked to user processes.
660 	 */
661 	memblock_reserve(0, SZ_64K);
662 
663 	early_reserve_initrd();
664 
665 	memblock_x86_reserve_range_setup_data();
666 
667 	reserve_bios_regions();
668 	trim_snb_memory();
669 }
670 
671 /*
672  * Dump out kernel offset information on panic.
673  */
674 static int
675 dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
676 {
677 	if (kaslr_enabled()) {
678 		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
679 			 kaslr_offset(),
680 			 __START_KERNEL,
681 			 __START_KERNEL_map,
682 			 MODULES_VADDR-1);
683 	} else {
684 		pr_emerg("Kernel Offset: disabled\n");
685 	}
686 
687 	return 0;
688 }
689 
690 void x86_configure_nx(void)
691 {
692 	if (boot_cpu_has(X86_FEATURE_NX))
693 		__supported_pte_mask |= _PAGE_NX;
694 	else
695 		__supported_pte_mask &= ~_PAGE_NX;
696 }
697 
698 static void __init x86_report_nx(void)
699 {
700 	if (!boot_cpu_has(X86_FEATURE_NX)) {
701 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
702 		       "missing in CPU!\n");
703 	} else {
704 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
705 		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
706 #else
707 		/* 32bit non-PAE kernel, NX cannot be used */
708 		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
709 		       "cannot be enabled: non-PAE kernel!\n");
710 #endif
711 	}
712 }
713 
714 /*
715  * Determine if we were loaded by an EFI loader.  If so, then we have also been
716  * passed the efi memmap, systab, etc., so we should use these data structures
717  * for initialization.  Note, the efi init code path is determined by the
718  * global efi_enabled. This allows the same kernel image to be used on existing
719  * systems (with a traditional BIOS) as well as on EFI systems.
720  */
721 /*
722  * setup_arch - architecture-specific boot-time initializations
723  *
724  * Note: On x86_64, fixmaps are ready for use even before this is called.
725  */
726 
727 void __init setup_arch(char **cmdline_p)
728 {
729 #ifdef CONFIG_X86_32
730 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
731 
732 	/*
733 	 * copy kernel address range established so far and switch
734 	 * to the proper swapper page table
735 	 */
736 	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
737 			initial_page_table + KERNEL_PGD_BOUNDARY,
738 			KERNEL_PGD_PTRS);
739 
740 	load_cr3(swapper_pg_dir);
741 	/*
742 	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
743 	 * a cr3 based tlb flush, so the following __flush_tlb_all()
744 	 * will not flush anything because the CPU quirk which clears
745 	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
746 	 * load_cr3() above the TLB has been flushed already. The
747 	 * quirk is invoked before subsequent calls to __flush_tlb_all()
748 	 * so proper operation is guaranteed.
749 	 */
750 	__flush_tlb_all();
751 #else
752 	printk(KERN_INFO "Command line: %s\n", boot_command_line);
753 	boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
754 #endif
755 
756 	/*
757 	 * If we have OLPC OFW, we might end up relocating the fixmap due to
758 	 * reserve_top(), so do this before touching the ioremap area.
759 	 */
760 	olpc_ofw_detect();
761 
762 	idt_setup_early_traps();
763 	early_cpu_init();
764 	jump_label_init();
765 	static_call_init();
766 	early_ioremap_init();
767 
768 	setup_olpc_ofw_pgd();
769 
770 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
771 	screen_info = boot_params.screen_info;
772 	edid_info = boot_params.edid_info;
773 #ifdef CONFIG_X86_32
774 	apm_info.bios = boot_params.apm_bios_info;
775 	ist_info = boot_params.ist_info;
776 #endif
777 	saved_video_mode = boot_params.hdr.vid_mode;
778 	bootloader_type = boot_params.hdr.type_of_loader;
779 	if ((bootloader_type >> 4) == 0xe) {
780 		bootloader_type &= 0xf;
781 		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
782 	}
783 	bootloader_version  = bootloader_type & 0xf;
784 	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
785 
786 #ifdef CONFIG_BLK_DEV_RAM
787 	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
788 #endif
789 #ifdef CONFIG_EFI
790 	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
791 		     EFI32_LOADER_SIGNATURE, 4)) {
792 		set_bit(EFI_BOOT, &efi.flags);
793 	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
794 		     EFI64_LOADER_SIGNATURE, 4)) {
795 		set_bit(EFI_BOOT, &efi.flags);
796 		set_bit(EFI_64BIT, &efi.flags);
797 	}
798 #endif
799 
800 	x86_init.oem.arch_setup();
801 
802 	/*
803 	 * Do some memory reservations *before* memory is added to memblock, so
804 	 * memblock allocations won't overwrite it.
805 	 *
806 	 * After this point, everything still needed from the boot loader or
807 	 * firmware or kernel text should be early reserved or marked not RAM in
808 	 * e820. All other memory is free game.
809 	 *
810 	 * This call needs to happen before e820__memory_setup() which calls the
811 	 * xen_memory_setup() on Xen dom0 which relies on the fact that those
812 	 * early reservations have happened already.
813 	 */
814 	early_reserve_memory();
815 
816 	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
817 	e820__memory_setup();
818 	parse_setup_data();
819 
820 	copy_edd();
821 
822 	if (!boot_params.hdr.root_flags)
823 		root_mountflags &= ~MS_RDONLY;
824 	setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
825 
826 	code_resource.start = __pa_symbol(_text);
827 	code_resource.end = __pa_symbol(_etext)-1;
828 	rodata_resource.start = __pa_symbol(__start_rodata);
829 	rodata_resource.end = __pa_symbol(__end_rodata)-1;
830 	data_resource.start = __pa_symbol(_sdata);
831 	data_resource.end = __pa_symbol(_edata)-1;
832 	bss_resource.start = __pa_symbol(__bss_start);
833 	bss_resource.end = __pa_symbol(__bss_stop)-1;
834 
835 #ifdef CONFIG_CMDLINE_BOOL
836 #ifdef CONFIG_CMDLINE_OVERRIDE
837 	strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
838 #else
839 	if (builtin_cmdline[0]) {
840 		/* append boot loader cmdline to builtin */
841 		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
842 		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
843 		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
844 	}
845 #endif
846 #endif
847 
848 	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
849 	*cmdline_p = command_line;
850 
851 	/*
852 	 * x86_configure_nx() is called before parse_early_param() to detect
853 	 * whether hardware doesn't support NX (so that the early EHCI debug
854 	 * console setup can safely call set_fixmap()).
855 	 */
856 	x86_configure_nx();
857 
858 	parse_early_param();
859 
860 	if (efi_enabled(EFI_BOOT))
861 		efi_memblock_x86_reserve_range();
862 
863 #ifdef CONFIG_MEMORY_HOTPLUG
864 	/*
865 	 * Memory used by the kernel cannot be hot-removed because Linux
866 	 * cannot migrate the kernel pages. When memory hotplug is
867 	 * enabled, we should prevent memblock from allocating memory
868 	 * for the kernel.
869 	 *
870 	 * ACPI SRAT records all hotpluggable memory ranges. But before
871 	 * SRAT is parsed, we don't know about it.
872 	 *
873 	 * The kernel image is loaded into memory at very early time. We
874 	 * cannot prevent this anyway. So on NUMA system, we set any
875 	 * node the kernel resides in as un-hotpluggable.
876 	 *
877 	 * Since on modern servers, one node could have double-digit
878 	 * gigabytes memory, we can assume the memory around the kernel
879 	 * image is also un-hotpluggable. So before SRAT is parsed, just
880 	 * allocate memory near the kernel image to try the best to keep
881 	 * the kernel away from hotpluggable memory.
882 	 */
883 	if (movable_node_is_enabled())
884 		memblock_set_bottom_up(true);
885 #endif
886 
887 	x86_report_nx();
888 
889 	apic_setup_apic_calls();
890 
891 	if (acpi_mps_check()) {
892 #ifdef CONFIG_X86_LOCAL_APIC
893 		apic_is_disabled = true;
894 #endif
895 		setup_clear_cpu_cap(X86_FEATURE_APIC);
896 	}
897 
898 	e820__reserve_setup_data();
899 	e820__finish_early_params();
900 
901 	if (efi_enabled(EFI_BOOT))
902 		efi_init();
903 
904 	reserve_ibft_region();
905 	dmi_setup();
906 
907 	/*
908 	 * VMware detection requires dmi to be available, so this
909 	 * needs to be done after dmi_setup(), for the boot CPU.
910 	 * For some guest types (Xen PV, SEV-SNP, TDX) it is required to be
911 	 * called before cache_bp_init() for setting up MTRR state.
912 	 */
913 	init_hypervisor_platform();
914 
915 	tsc_early_init();
916 	x86_init.resources.probe_roms();
917 
918 	/* after parse_early_param, so could debug it */
919 	insert_resource(&iomem_resource, &code_resource);
920 	insert_resource(&iomem_resource, &rodata_resource);
921 	insert_resource(&iomem_resource, &data_resource);
922 	insert_resource(&iomem_resource, &bss_resource);
923 
924 	e820_add_kernel_range();
925 	trim_bios_range();
926 #ifdef CONFIG_X86_32
927 	if (ppro_with_ram_bug()) {
928 		e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
929 				  E820_TYPE_RESERVED);
930 		e820__update_table(e820_table);
931 		printk(KERN_INFO "fixed physical RAM map:\n");
932 		e820__print_table("bad_ppro");
933 	}
934 #else
935 	early_gart_iommu_check();
936 #endif
937 
938 	/*
939 	 * partially used pages are not usable - thus
940 	 * we are rounding upwards:
941 	 */
942 	max_pfn = e820__end_of_ram_pfn();
943 
944 	/* update e820 for memory not covered by WB MTRRs */
945 	cache_bp_init();
946 	if (mtrr_trim_uncached_memory(max_pfn))
947 		max_pfn = e820__end_of_ram_pfn();
948 
949 	max_possible_pfn = max_pfn;
950 
951 	/*
952 	 * Define random base addresses for memory sections after max_pfn is
953 	 * defined and before each memory section base is used.
954 	 */
955 	kernel_randomize_memory();
956 
957 #ifdef CONFIG_X86_32
958 	/* max_low_pfn get updated here */
959 	find_low_pfn_range();
960 #else
961 	check_x2apic();
962 
963 	/* How many end-of-memory variables you have, grandma! */
964 	/* need this before calling reserve_initrd */
965 	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
966 		max_low_pfn = e820__end_of_low_ram_pfn();
967 	else
968 		max_low_pfn = max_pfn;
969 
970 	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
971 #endif
972 
973 	/*
974 	 * Find and reserve possible boot-time SMP configuration:
975 	 */
976 	find_smp_config();
977 
978 	early_alloc_pgt_buf();
979 
980 	/*
981 	 * Need to conclude brk, before e820__memblock_setup()
982 	 * it could use memblock_find_in_range, could overlap with
983 	 * brk area.
984 	 */
985 	reserve_brk();
986 
987 	cleanup_highmap();
988 
989 	memblock_set_current_limit(ISA_END_ADDRESS);
990 	e820__memblock_setup();
991 
992 	/*
993 	 * Needs to run after memblock setup because it needs the physical
994 	 * memory size.
995 	 */
996 	mem_encrypt_setup_arch();
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 	early_acpi_boot_init();
1094 
1095 	x86_flattree_get_config();
1096 
1097 	initmem_init();
1098 	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1099 
1100 	if (boot_cpu_has(X86_FEATURE_GBPAGES))
1101 		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1102 
1103 	/*
1104 	 * Reserve memory for crash kernel after SRAT is parsed so that it
1105 	 * won't consume hotpluggable memory.
1106 	 */
1107 	arch_reserve_crashkernel();
1108 
1109 	memblock_find_dma_reserve();
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 	/*
1135 	 * Read APIC and some other early information from ACPI tables.
1136 	 */
1137 	acpi_boot_init();
1138 	x86_dtb_init();
1139 
1140 	/*
1141 	 * get boot-time SMP configuration:
1142 	 */
1143 	get_smp_config();
1144 
1145 	/*
1146 	 * Systems w/o ACPI and mptables might not have it mapped the local
1147 	 * APIC yet, but prefill_possible_map() might need to access it.
1148 	 */
1149 	init_apic_mappings();
1150 
1151 	prefill_possible_map();
1152 
1153 	init_cpu_to_node();
1154 	init_gi_nodes();
1155 
1156 	io_apic_init_mappings();
1157 
1158 	x86_init.hyper.guest_late_init();
1159 
1160 	e820__reserve_resources();
1161 	e820__register_nosave_regions(max_pfn);
1162 
1163 	x86_init.resources.reserve_resources();
1164 
1165 	e820__setup_pci_gap();
1166 
1167 #ifdef CONFIG_VT
1168 #if defined(CONFIG_VGA_CONSOLE)
1169 	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1170 		vgacon_register_screen(&screen_info);
1171 #endif
1172 #endif
1173 	x86_init.oem.banner();
1174 
1175 	x86_init.timers.wallclock_init();
1176 
1177 	/*
1178 	 * This needs to run before setup_local_APIC() which soft-disables the
1179 	 * local APIC temporarily and that masks the thermal LVT interrupt,
1180 	 * leading to softlockups on machines which have configured SMI
1181 	 * interrupt delivery.
1182 	 */
1183 	therm_lvt_init();
1184 
1185 	mcheck_init();
1186 
1187 	register_refined_jiffies(CLOCK_TICK_RATE);
1188 
1189 #ifdef CONFIG_EFI
1190 	if (efi_enabled(EFI_BOOT))
1191 		efi_apply_memmap_quirks();
1192 #endif
1193 
1194 	unwind_init();
1195 }
1196 
1197 #ifdef CONFIG_X86_32
1198 
1199 static struct resource video_ram_resource = {
1200 	.name	= "Video RAM area",
1201 	.start	= 0xa0000,
1202 	.end	= 0xbffff,
1203 	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1204 };
1205 
1206 void __init i386_reserve_resources(void)
1207 {
1208 	request_resource(&iomem_resource, &video_ram_resource);
1209 	reserve_standard_io_resources();
1210 }
1211 
1212 #endif /* CONFIG_X86_32 */
1213 
1214 static struct notifier_block kernel_offset_notifier = {
1215 	.notifier_call = dump_kernel_offset
1216 };
1217 
1218 static int __init register_kernel_offset_dumper(void)
1219 {
1220 	atomic_notifier_chain_register(&panic_notifier_list,
1221 					&kernel_offset_notifier);
1222 	return 0;
1223 }
1224 __initcall(register_kernel_offset_dumper);
1225