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 */
  66unsigned long max_low_pfn_mapped;
  67unsigned long max_pfn_mapped;
  68
  69#ifdef CONFIG_DMI
  70RESERVE_BRK(dmi_alloc, 65536);
  71#endif
  72
  73
  74unsigned long _brk_start = (unsigned long)__brk_base;
  75unsigned long _brk_end   = (unsigned long)__brk_base;
  76
  77struct 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
  85static struct resource rodata_resource = {
  86	.name	= "Kernel rodata",
  87	.start	= 0,
  88	.end	= 0,
  89	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
  90};
  91
  92static struct resource data_resource = {
  93	.name	= "Kernel data",
  94	.start	= 0,
  95	.end	= 0,
  96	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
  97};
  98
  99static struct resource code_resource = {
 100	.name	= "Kernel code",
 101	.start	= 0,
 102	.end	= 0,
 103	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
 104};
 105
 106static 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 */
 116struct cpuinfo_x86 new_cpu_data;
 117
 118struct apm_info apm_info;
 119EXPORT_SYMBOL(apm_info);
 120
 121#if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
 122	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
 123struct ist_info ist_info;
 124EXPORT_SYMBOL(ist_info);
 125#else
 126struct ist_info ist_info;
 127#endif
 128
 129#endif
 130
 131struct cpuinfo_x86 boot_cpu_data __read_mostly;
 132EXPORT_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
 141static phys_addr_t ima_kexec_buffer_phys;
 142static size_t ima_kexec_buffer_size;
 143#endif
 144
 145/* Boot loader ID and version as integers, for the benefit of proc_dointvec */
 146int bootloader_type, bootloader_version;
 147
 148/*
 149 * Setup options
 150 */
 151struct screen_info screen_info;
 152EXPORT_SYMBOL(screen_info);
 153struct edid_info edid_info;
 154EXPORT_SYMBOL_GPL(edid_info);
 155
 156extern int root_mountflags;
 157
 158unsigned 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
 164static char __initdata command_line[COMMAND_LINE_SIZE];
 165#ifdef CONFIG_CMDLINE_BOOL
 166static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
 167#endif
 168
 169#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 170struct edd edd;
 171#ifdef CONFIG_EDD_MODULE
 172EXPORT_SYMBOL(edd);
 173#endif
 174/**
 175 * copy_edd() - Copy the BIOS EDD information
 176 *              from boot_params into a safe place.
 177 *
 178 */
 179static 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
 188static inline void __init copy_edd(void)
 189{
 190}
 191#endif
 192
 193void * __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
 213static void __init cleanup_highmap(void)
 214{
 215}
 216#endif
 217
 218static 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
 231static 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}
 242static 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
 254static 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
 281static 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
 295static 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
 325static void __init early_reserve_initrd(void)
 326{
 327}
 328static void __init reserve_initrd(void)
 329{
 330}
 331#endif /* CONFIG_BLK_DEV_INITRD */
 332
 333static 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)
 357int __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
 371int __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
 383static 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
 427static 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
 467static 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
 492static 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
 515void __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
 525static 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 */
 561static 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
 595static 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 */
 619static 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
 639static 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 */
 674static int
 675dump_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
 690void 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
 698static 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
 727void __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
1199static struct resource video_ram_resource = {
1200	.name	= "Video RAM area",
1201	.start	= 0xa0000,
1202	.end	= 0xbffff,
1203	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1204};
1205
1206void __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
1214static struct notifier_block kernel_offset_notifier = {
1215	.notifier_call = dump_kernel_offset
1216};
1217
1218static 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);