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v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  Copyright (C) 1995  Linus Torvalds
   4 *
   5 * This file contains the setup_arch() code, which handles the architecture-dependent
   6 * parts of early kernel initialization.
   7 */
   8#include <linux/acpi.h>
   9#include <linux/console.h>
  10#include <linux/cpu.h>
  11#include <linux/crash_dump.h>
  12#include <linux/dma-map-ops.h>
 
  13#include <linux/efi.h>
  14#include <linux/ima.h>
  15#include <linux/init_ohci1394_dma.h>
  16#include <linux/initrd.h>
  17#include <linux/iscsi_ibft.h>
  18#include <linux/memblock.h>
  19#include <linux/panic_notifier.h>
  20#include <linux/pci.h>
  21#include <linux/root_dev.h>
  22#include <linux/hugetlb.h>
  23#include <linux/tboot.h>
  24#include <linux/usb/xhci-dbgp.h>
  25#include <linux/static_call.h>
  26#include <linux/swiotlb.h>
  27#include <linux/random.h>
  28
  29#include <uapi/linux/mount.h>
  30
  31#include <xen/xen.h>
  32
  33#include <asm/apic.h>
  34#include <asm/efi.h>
  35#include <asm/numa.h>
  36#include <asm/bios_ebda.h>
  37#include <asm/bugs.h>
  38#include <asm/cacheinfo.h>
  39#include <asm/coco.h>
  40#include <asm/cpu.h>
  41#include <asm/efi.h>
  42#include <asm/gart.h>
  43#include <asm/hypervisor.h>
  44#include <asm/io_apic.h>
  45#include <asm/kasan.h>
  46#include <asm/kaslr.h>
  47#include <asm/mce.h>
  48#include <asm/memtype.h>
  49#include <asm/mtrr.h>
  50#include <asm/realmode.h>
  51#include <asm/olpc_ofw.h>
  52#include <asm/pci-direct.h>
  53#include <asm/prom.h>
  54#include <asm/proto.h>
  55#include <asm/thermal.h>
  56#include <asm/unwind.h>
  57#include <asm/vsyscall.h>
  58#include <linux/vmalloc.h>
  59
  60/*
  61 * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
  62 * max_pfn_mapped:     highest directly mapped pfn > 4 GB
  63 *
  64 * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
  65 * represented by pfn_mapped[].
  66 */
  67unsigned long max_low_pfn_mapped;
  68unsigned long max_pfn_mapped;
  69
  70#ifdef CONFIG_DMI
  71RESERVE_BRK(dmi_alloc, 65536);
  72#endif
  73
  74
 
 
 
 
 
  75unsigned long _brk_start = (unsigned long)__brk_base;
  76unsigned long _brk_end   = (unsigned long)__brk_base;
  77
  78struct 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
  86static struct resource rodata_resource = {
  87	.name	= "Kernel rodata",
  88	.start	= 0,
  89	.end	= 0,
  90	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
  91};
  92
  93static struct resource data_resource = {
  94	.name	= "Kernel data",
  95	.start	= 0,
  96	.end	= 0,
  97	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
  98};
  99
 100static struct resource code_resource = {
 101	.name	= "Kernel code",
 102	.start	= 0,
 103	.end	= 0,
 104	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
 105};
 106
 107static 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 */
 117struct cpuinfo_x86 new_cpu_data;
 118
 
 
 
 
 
 
 119struct apm_info apm_info;
 120EXPORT_SYMBOL(apm_info);
 121
 122#if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
 123	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
 124struct ist_info ist_info;
 125EXPORT_SYMBOL(ist_info);
 126#else
 127struct ist_info ist_info;
 128#endif
 129
 130#endif
 131
 132struct cpuinfo_x86 boot_cpu_data __read_mostly;
 133EXPORT_SYMBOL(boot_cpu_data);
 
 
 134
 135#if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
 136__visible unsigned long mmu_cr4_features __ro_after_init;
 137#else
 138__visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
 139#endif
 140
 141#ifdef CONFIG_IMA
 142static phys_addr_t ima_kexec_buffer_phys;
 143static size_t ima_kexec_buffer_size;
 144#endif
 145
 146/* Boot loader ID and version as integers, for the benefit of proc_dointvec */
 147int bootloader_type, bootloader_version;
 148
 149/*
 150 * Setup options
 151 */
 152struct screen_info screen_info;
 153EXPORT_SYMBOL(screen_info);
 154struct edid_info edid_info;
 155EXPORT_SYMBOL_GPL(edid_info);
 156
 157extern int root_mountflags;
 158
 159unsigned long saved_video_mode;
 160
 161#define RAMDISK_IMAGE_START_MASK	0x07FF
 162#define RAMDISK_PROMPT_FLAG		0x8000
 163#define RAMDISK_LOAD_FLAG		0x4000
 164
 165static char __initdata command_line[COMMAND_LINE_SIZE];
 166#ifdef CONFIG_CMDLINE_BOOL
 167char builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
 168bool builtin_cmdline_added __ro_after_init;
 169#endif
 170
 171#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 172struct edd edd;
 173#ifdef CONFIG_EDD_MODULE
 174EXPORT_SYMBOL(edd);
 175#endif
 176/**
 177 * copy_edd() - Copy the BIOS EDD information
 178 *              from boot_params into a safe place.
 179 *
 180 */
 181static inline void __init copy_edd(void)
 182{
 183     memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
 184	    sizeof(edd.mbr_signature));
 185     memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
 186     edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
 187     edd.edd_info_nr = boot_params.eddbuf_entries;
 188}
 189#else
 190static inline void __init copy_edd(void)
 191{
 192}
 193#endif
 194
 195void * __init extend_brk(size_t size, size_t align)
 196{
 197	size_t mask = align - 1;
 198	void *ret;
 199
 200	BUG_ON(_brk_start == 0);
 201	BUG_ON(align & mask);
 202
 203	_brk_end = (_brk_end + mask) & ~mask;
 204	BUG_ON((char *)(_brk_end + size) > __brk_limit);
 205
 206	ret = (void *)_brk_end;
 207	_brk_end += size;
 208
 209	memset(ret, 0, size);
 210
 211	return ret;
 212}
 213
 214#ifdef CONFIG_X86_32
 215static void __init cleanup_highmap(void)
 216{
 217}
 218#endif
 219
 220static void __init reserve_brk(void)
 221{
 222	if (_brk_end > _brk_start)
 223		memblock_reserve(__pa_symbol(_brk_start),
 224				 _brk_end - _brk_start);
 225
 226	/* Mark brk area as locked down and no longer taking any
 227	   new allocations */
 228	_brk_start = 0;
 229}
 230
 
 
 231#ifdef CONFIG_BLK_DEV_INITRD
 232
 233static u64 __init get_ramdisk_image(void)
 234{
 235	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 236
 237	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
 238
 239	if (ramdisk_image == 0)
 240		ramdisk_image = phys_initrd_start;
 241
 242	return ramdisk_image;
 243}
 244static u64 __init get_ramdisk_size(void)
 245{
 246	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
 247
 248	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
 249
 250	if (ramdisk_size == 0)
 251		ramdisk_size = phys_initrd_size;
 252
 253	return ramdisk_size;
 254}
 255
 256static void __init relocate_initrd(void)
 257{
 258	/* Assume only end is not page aligned */
 259	u64 ramdisk_image = get_ramdisk_image();
 260	u64 ramdisk_size  = get_ramdisk_size();
 261	u64 area_size     = PAGE_ALIGN(ramdisk_size);
 262
 263	/* We need to move the initrd down into directly mapped mem */
 264	u64 relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
 265						      PFN_PHYS(max_pfn_mapped));
 266	if (!relocated_ramdisk)
 267		panic("Cannot find place for new RAMDISK of size %lld\n",
 268		      ramdisk_size);
 269
 270	initrd_start = relocated_ramdisk + PAGE_OFFSET;
 271	initrd_end   = initrd_start + ramdisk_size;
 272	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
 273	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
 274
 275	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
 276
 277	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
 278		" [mem %#010llx-%#010llx]\n",
 279		ramdisk_image, ramdisk_image + ramdisk_size - 1,
 280		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
 281}
 282
 283static void __init early_reserve_initrd(void)
 284{
 285	/* Assume only end is not page aligned */
 286	u64 ramdisk_image = get_ramdisk_image();
 287	u64 ramdisk_size  = get_ramdisk_size();
 288	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
 289
 290	if (!boot_params.hdr.type_of_loader ||
 291	    !ramdisk_image || !ramdisk_size)
 292		return;		/* No initrd provided by bootloader */
 293
 294	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
 295}
 296
 297static void __init reserve_initrd(void)
 298{
 299	/* Assume only end is not page aligned */
 300	u64 ramdisk_image = get_ramdisk_image();
 301	u64 ramdisk_size  = get_ramdisk_size();
 302	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
 303
 304	if (!boot_params.hdr.type_of_loader ||
 305	    !ramdisk_image || !ramdisk_size)
 306		return;		/* No initrd provided by bootloader */
 307
 308	initrd_start = 0;
 309
 310	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
 311			ramdisk_end - 1);
 312
 313	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
 314				PFN_DOWN(ramdisk_end))) {
 315		/* All are mapped, easy case */
 316		initrd_start = ramdisk_image + PAGE_OFFSET;
 317		initrd_end = initrd_start + ramdisk_size;
 318		return;
 319	}
 320
 321	relocate_initrd();
 322
 323	memblock_phys_free(ramdisk_image, ramdisk_end - ramdisk_image);
 324}
 325
 326#else
 327static void __init early_reserve_initrd(void)
 328{
 329}
 330static void __init reserve_initrd(void)
 331{
 332}
 333#endif /* CONFIG_BLK_DEV_INITRD */
 334
 335static void __init add_early_ima_buffer(u64 phys_addr)
 336{
 337#ifdef CONFIG_IMA
 338	struct ima_setup_data *data;
 339
 340	data = early_memremap(phys_addr + sizeof(struct setup_data), sizeof(*data));
 341	if (!data) {
 342		pr_warn("setup: failed to memremap ima_setup_data entry\n");
 343		return;
 344	}
 345
 346	if (data->size) {
 347		memblock_reserve(data->addr, data->size);
 348		ima_kexec_buffer_phys = data->addr;
 349		ima_kexec_buffer_size = data->size;
 350	}
 351
 352	early_memunmap(data, sizeof(*data));
 353#else
 354	pr_warn("Passed IMA kexec data, but CONFIG_IMA not set. Ignoring.\n");
 355#endif
 356}
 357
 358#if defined(CONFIG_HAVE_IMA_KEXEC) && !defined(CONFIG_OF_FLATTREE)
 359int __init ima_free_kexec_buffer(void)
 360{
 361	if (!ima_kexec_buffer_size)
 362		return -ENOENT;
 363
 364	memblock_free_late(ima_kexec_buffer_phys,
 365			   ima_kexec_buffer_size);
 366
 367	ima_kexec_buffer_phys = 0;
 368	ima_kexec_buffer_size = 0;
 369
 370	return 0;
 371}
 372
 373int __init ima_get_kexec_buffer(void **addr, size_t *size)
 374{
 375	if (!ima_kexec_buffer_size)
 376		return -ENOENT;
 377
 378	*addr = __va(ima_kexec_buffer_phys);
 379	*size = ima_kexec_buffer_size;
 380
 381	return 0;
 382}
 383#endif
 384
 385static void __init parse_setup_data(void)
 386{
 387	struct setup_data *data;
 388	u64 pa_data, pa_next;
 389
 390	pa_data = boot_params.hdr.setup_data;
 391	while (pa_data) {
 392		u32 data_len, data_type;
 393
 394		data = early_memremap(pa_data, sizeof(*data));
 395		data_len = data->len + sizeof(struct setup_data);
 396		data_type = data->type;
 397		pa_next = data->next;
 398		early_memunmap(data, sizeof(*data));
 399
 400		switch (data_type) {
 401		case SETUP_E820_EXT:
 402			e820__memory_setup_extended(pa_data, data_len);
 403			break;
 404		case SETUP_DTB:
 405			add_dtb(pa_data);
 406			break;
 407		case SETUP_EFI:
 408			parse_efi_setup(pa_data, data_len);
 409			break;
 410		case SETUP_IMA:
 411			add_early_ima_buffer(pa_data);
 412			break;
 413		case SETUP_RNG_SEED:
 414			data = early_memremap(pa_data, data_len);
 415			add_bootloader_randomness(data->data, data->len);
 416			/* Zero seed for forward secrecy. */
 417			memzero_explicit(data->data, data->len);
 418			/* Zero length in case we find ourselves back here by accident. */
 419			memzero_explicit(&data->len, sizeof(data->len));
 420			early_memunmap(data, data_len);
 421			break;
 422		default:
 423			break;
 424		}
 425		pa_data = pa_next;
 426	}
 427}
 428
 429static void __init memblock_x86_reserve_range_setup_data(void)
 430{
 431	struct setup_indirect *indirect;
 432	struct setup_data *data;
 433	u64 pa_data, pa_next;
 434	u32 len;
 435
 436	pa_data = boot_params.hdr.setup_data;
 437	while (pa_data) {
 438		data = early_memremap(pa_data, sizeof(*data));
 439		if (!data) {
 440			pr_warn("setup: failed to memremap setup_data entry\n");
 441			return;
 442		}
 443
 444		len = sizeof(*data);
 445		pa_next = data->next;
 
 
 446
 447		memblock_reserve(pa_data, sizeof(*data) + data->len);
 
 
 
 448
 449		if (data->type == SETUP_INDIRECT) {
 450			len += data->len;
 451			early_memunmap(data, sizeof(*data));
 452			data = early_memremap(pa_data, len);
 453			if (!data) {
 454				pr_warn("setup: failed to memremap indirect setup_data\n");
 455				return;
 456			}
 457
 458			indirect = (struct setup_indirect *)data->data;
 459
 460			if (indirect->type != SETUP_INDIRECT)
 461				memblock_reserve(indirect->addr, indirect->len);
 462		}
 463
 464		pa_data = pa_next;
 465		early_memunmap(data, len);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 466	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 467}
 468
 469static void __init arch_reserve_crashkernel(void)
 470{
 471	unsigned long long crash_base, crash_size, low_size = 0;
 472	char *cmdline = boot_command_line;
 473	bool high = false;
 474	int ret;
 475
 476	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
 477		return;
 478
 479	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
 480				&crash_size, &crash_base,
 481				&low_size, &high);
 482	if (ret)
 483		return;
 
 
 
 
 
 484
 485	if (xen_pv_domain()) {
 486		pr_info("Ignoring crashkernel for a Xen PV domain\n");
 487		return;
 488	}
 489
 490	reserve_crashkernel_generic(cmdline, crash_size, crash_base,
 491				    low_size, high);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 492}
 
 
 
 
 
 493
 494static struct resource standard_io_resources[] = {
 495	{ .name = "dma1", .start = 0x00, .end = 0x1f,
 496		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 497	{ .name = "pic1", .start = 0x20, .end = 0x21,
 498		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 499	{ .name = "timer0", .start = 0x40, .end = 0x43,
 500		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 501	{ .name = "timer1", .start = 0x50, .end = 0x53,
 502		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 503	{ .name = "keyboard", .start = 0x60, .end = 0x60,
 504		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 505	{ .name = "keyboard", .start = 0x64, .end = 0x64,
 506		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 507	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
 508		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 509	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
 510		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 511	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
 512		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 513	{ .name = "fpu", .start = 0xf0, .end = 0xff,
 514		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
 515};
 516
 517void __init reserve_standard_io_resources(void)
 518{
 519	int i;
 520
 521	/* request I/O space for devices used on all i[345]86 PCs */
 522	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
 523		request_resource(&ioport_resource, &standard_io_resources[i]);
 524
 525}
 526
 
 
 
 
 
 
 
 
 
 
 527static bool __init snb_gfx_workaround_needed(void)
 528{
 529#ifdef CONFIG_PCI
 530	int i;
 531	u16 vendor, devid;
 532	static const __initconst u16 snb_ids[] = {
 533		0x0102,
 534		0x0112,
 535		0x0122,
 536		0x0106,
 537		0x0116,
 538		0x0126,
 539		0x010a,
 540	};
 541
 542	/* Assume no if something weird is going on with PCI */
 543	if (!early_pci_allowed())
 544		return false;
 545
 546	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
 547	if (vendor != 0x8086)
 548		return false;
 549
 550	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
 551	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
 552		if (devid == snb_ids[i])
 553			return true;
 554#endif
 555
 556	return false;
 557}
 558
 559/*
 560 * Sandy Bridge graphics has trouble with certain ranges, exclude
 561 * them from allocation.
 562 */
 563static void __init trim_snb_memory(void)
 564{
 565	static const __initconst unsigned long bad_pages[] = {
 566		0x20050000,
 567		0x20110000,
 568		0x20130000,
 569		0x20138000,
 570		0x40004000,
 571	};
 572	int i;
 573
 574	if (!snb_gfx_workaround_needed())
 575		return;
 576
 577	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
 578
 579	/*
 580	 * SandyBridge integrated graphics devices have a bug that prevents
 581	 * them from accessing certain memory ranges, namely anything below
 582	 * 1M and in the pages listed in bad_pages[] above.
 583	 *
 584	 * To avoid these pages being ever accessed by SNB gfx devices reserve
 585	 * bad_pages that have not already been reserved at boot time.
 586	 * All memory below the 1 MB mark is anyway reserved later during
 587	 * setup_arch(), so there is no need to reserve it here.
 588	 */
 589
 590	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
 591		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
 592			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
 593			       bad_pages[i]);
 594	}
 595}
 596
 597static void __init trim_bios_range(void)
 598{
 599	/*
 600	 * A special case is the first 4Kb of memory;
 601	 * This is a BIOS owned area, not kernel ram, but generally
 602	 * not listed as such in the E820 table.
 603	 *
 604	 * This typically reserves additional memory (64KiB by default)
 605	 * since some BIOSes are known to corrupt low memory.  See the
 606	 * Kconfig help text for X86_RESERVE_LOW.
 607	 */
 608	e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
 609
 610	/*
 611	 * special case: Some BIOSes report the PC BIOS
 612	 * area (640Kb -> 1Mb) as RAM even though it is not.
 613	 * take them out.
 614	 */
 615	e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
 616
 617	e820__update_table(e820_table);
 618}
 619
 620/* called before trim_bios_range() to spare extra sanitize */
 621static void __init e820_add_kernel_range(void)
 622{
 623	u64 start = __pa_symbol(_text);
 624	u64 size = __pa_symbol(_end) - start;
 625
 626	/*
 627	 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
 628	 * attempt to fix it by adding the range. We may have a confused BIOS,
 629	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
 630	 * exclude kernel range. If we really are running on top non-RAM,
 631	 * we will crash later anyways.
 632	 */
 633	if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
 634		return;
 635
 636	pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
 637	e820__range_remove(start, size, E820_TYPE_RAM, 0);
 638	e820__range_add(start, size, E820_TYPE_RAM);
 639}
 640
 641static void __init early_reserve_memory(void)
 642{
 643	/*
 644	 * Reserve the memory occupied by the kernel between _text and
 645	 * __end_of_kernel_reserve symbols. Any kernel sections after the
 646	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
 647	 * separate memblock_reserve() or they will be discarded.
 648	 */
 649	memblock_reserve(__pa_symbol(_text),
 650			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
 651
 652	/*
 653	 * The first 4Kb of memory is a BIOS owned area, but generally it is
 654	 * not listed as such in the E820 table.
 655	 *
 656	 * Reserve the first 64K of memory since some BIOSes are known to
 657	 * corrupt low memory. After the real mode trampoline is allocated the
 658	 * rest of the memory below 640k is reserved.
 659	 *
 660	 * In addition, make sure page 0 is always reserved because on
 661	 * systems with L1TF its contents can be leaked to user processes.
 662	 */
 663	memblock_reserve(0, SZ_64K);
 664
 665	early_reserve_initrd();
 666
 
 
 
 667	memblock_x86_reserve_range_setup_data();
 668
 
 669	reserve_bios_regions();
 670	trim_snb_memory();
 671}
 672
 673/*
 674 * Dump out kernel offset information on panic.
 675 */
 676static int
 677dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
 678{
 679	if (kaslr_enabled()) {
 680		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
 681			 kaslr_offset(),
 682			 __START_KERNEL,
 683			 __START_KERNEL_map,
 684			 MODULES_VADDR-1);
 685	} else {
 686		pr_emerg("Kernel Offset: disabled\n");
 687	}
 688
 689	return 0;
 690}
 691
 692void x86_configure_nx(void)
 693{
 694	if (boot_cpu_has(X86_FEATURE_NX))
 695		__supported_pte_mask |= _PAGE_NX;
 696	else
 697		__supported_pte_mask &= ~_PAGE_NX;
 698}
 699
 700static void __init x86_report_nx(void)
 701{
 702	if (!boot_cpu_has(X86_FEATURE_NX)) {
 703		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
 704		       "missing in CPU!\n");
 705	} else {
 706#if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
 707		printk(KERN_INFO "NX (Execute Disable) protection: active\n");
 708#else
 709		/* 32bit non-PAE kernel, NX cannot be used */
 710		printk(KERN_NOTICE "Notice: NX (Execute Disable) protection "
 711		       "cannot be enabled: non-PAE kernel!\n");
 712#endif
 713	}
 714}
 715
 716/*
 717 * Determine if we were loaded by an EFI loader.  If so, then we have also been
 718 * passed the efi memmap, systab, etc., so we should use these data structures
 719 * for initialization.  Note, the efi init code path is determined by the
 720 * global efi_enabled. This allows the same kernel image to be used on existing
 721 * systems (with a traditional BIOS) as well as on EFI systems.
 722 */
 723/*
 724 * setup_arch - architecture-specific boot-time initializations
 725 *
 726 * Note: On x86_64, fixmaps are ready for use even before this is called.
 727 */
 728
 729void __init setup_arch(char **cmdline_p)
 730{
 731#ifdef CONFIG_X86_32
 732	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
 733
 734	/*
 735	 * copy kernel address range established so far and switch
 736	 * to the proper swapper page table
 737	 */
 738	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
 739			initial_page_table + KERNEL_PGD_BOUNDARY,
 740			KERNEL_PGD_PTRS);
 741
 742	load_cr3(swapper_pg_dir);
 743	/*
 744	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
 745	 * a cr3 based tlb flush, so the following __flush_tlb_all()
 746	 * will not flush anything because the CPU quirk which clears
 747	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
 748	 * load_cr3() above the TLB has been flushed already. The
 749	 * quirk is invoked before subsequent calls to __flush_tlb_all()
 750	 * so proper operation is guaranteed.
 751	 */
 752	__flush_tlb_all();
 753#else
 754	printk(KERN_INFO "Command line: %s\n", boot_command_line);
 755	boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
 756#endif
 757
 758#ifdef CONFIG_CMDLINE_BOOL
 759#ifdef CONFIG_CMDLINE_OVERRIDE
 760	strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
 761#else
 762	if (builtin_cmdline[0]) {
 763		/* append boot loader cmdline to builtin */
 764		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
 765		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
 766		strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
 767	}
 768#endif
 769	builtin_cmdline_added = true;
 770#endif
 771
 772	strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
 773	*cmdline_p = command_line;
 774
 775	/*
 776	 * If we have OLPC OFW, we might end up relocating the fixmap due to
 777	 * reserve_top(), so do this before touching the ioremap area.
 778	 */
 779	olpc_ofw_detect();
 780
 781	idt_setup_early_traps();
 782	early_cpu_init();
 783	jump_label_init();
 784	static_call_init();
 785	early_ioremap_init();
 786
 787	setup_olpc_ofw_pgd();
 788
 789	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
 790	screen_info = boot_params.screen_info;
 791	edid_info = boot_params.edid_info;
 792#ifdef CONFIG_X86_32
 793	apm_info.bios = boot_params.apm_bios_info;
 794	ist_info = boot_params.ist_info;
 795#endif
 796	saved_video_mode = boot_params.hdr.vid_mode;
 797	bootloader_type = boot_params.hdr.type_of_loader;
 798	if ((bootloader_type >> 4) == 0xe) {
 799		bootloader_type &= 0xf;
 800		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
 801	}
 802	bootloader_version  = bootloader_type & 0xf;
 803	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
 804
 805#ifdef CONFIG_BLK_DEV_RAM
 806	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
 807#endif
 808#ifdef CONFIG_EFI
 809	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
 810		     EFI32_LOADER_SIGNATURE, 4)) {
 811		set_bit(EFI_BOOT, &efi.flags);
 812	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
 813		     EFI64_LOADER_SIGNATURE, 4)) {
 814		set_bit(EFI_BOOT, &efi.flags);
 815		set_bit(EFI_64BIT, &efi.flags);
 816	}
 817#endif
 818
 819	x86_init.oem.arch_setup();
 820
 821	/*
 822	 * Do some memory reservations *before* memory is added to memblock, so
 823	 * memblock allocations won't overwrite it.
 824	 *
 825	 * After this point, everything still needed from the boot loader or
 826	 * firmware or kernel text should be early reserved or marked not RAM in
 827	 * e820. All other memory is free game.
 828	 *
 829	 * This call needs to happen before e820__memory_setup() which calls the
 830	 * xen_memory_setup() on Xen dom0 which relies on the fact that those
 831	 * early reservations have happened already.
 832	 */
 833	early_reserve_memory();
 834
 835	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
 836	e820__memory_setup();
 837	parse_setup_data();
 838
 839	copy_edd();
 840
 841	if (!boot_params.hdr.root_flags)
 842		root_mountflags &= ~MS_RDONLY;
 843	setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
 844
 845	code_resource.start = __pa_symbol(_text);
 846	code_resource.end = __pa_symbol(_etext)-1;
 847	rodata_resource.start = __pa_symbol(__start_rodata);
 848	rodata_resource.end = __pa_symbol(__end_rodata)-1;
 849	data_resource.start = __pa_symbol(_sdata);
 850	data_resource.end = __pa_symbol(_edata)-1;
 851	bss_resource.start = __pa_symbol(__bss_start);
 852	bss_resource.end = __pa_symbol(__bss_stop)-1;
 853
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 854	/*
 855	 * x86_configure_nx() is called before parse_early_param() to detect
 856	 * whether hardware doesn't support NX (so that the early EHCI debug
 857	 * console setup can safely call set_fixmap()).
 
 
 858	 */
 859	x86_configure_nx();
 860
 861	parse_early_param();
 862
 863	if (efi_enabled(EFI_BOOT))
 864		efi_memblock_x86_reserve_range();
 865
 866#ifdef CONFIG_MEMORY_HOTPLUG
 867	/*
 868	 * Memory used by the kernel cannot be hot-removed because Linux
 869	 * cannot migrate the kernel pages. When memory hotplug is
 870	 * enabled, we should prevent memblock from allocating memory
 871	 * for the kernel.
 872	 *
 873	 * ACPI SRAT records all hotpluggable memory ranges. But before
 874	 * SRAT is parsed, we don't know about it.
 875	 *
 876	 * The kernel image is loaded into memory at very early time. We
 877	 * cannot prevent this anyway. So on NUMA system, we set any
 878	 * node the kernel resides in as un-hotpluggable.
 879	 *
 880	 * Since on modern servers, one node could have double-digit
 881	 * gigabytes memory, we can assume the memory around the kernel
 882	 * image is also un-hotpluggable. So before SRAT is parsed, just
 883	 * allocate memory near the kernel image to try the best to keep
 884	 * the kernel away from hotpluggable memory.
 885	 */
 886	if (movable_node_is_enabled())
 887		memblock_set_bottom_up(true);
 888#endif
 889
 890	x86_report_nx();
 891
 892	apic_setup_apic_calls();
 893
 894	if (acpi_mps_check()) {
 895#ifdef CONFIG_X86_LOCAL_APIC
 896		apic_is_disabled = true;
 897#endif
 898		setup_clear_cpu_cap(X86_FEATURE_APIC);
 899	}
 900
 901	e820__reserve_setup_data();
 902	e820__finish_early_params();
 903
 904	if (efi_enabled(EFI_BOOT))
 905		efi_init();
 906
 907	reserve_ibft_region();
 908	x86_init.resources.dmi_setup();
 909
 910	/*
 911	 * VMware detection requires dmi to be available, so this
 912	 * needs to be done after dmi_setup(), for the boot CPU.
 913	 * For some guest types (Xen PV, SEV-SNP, TDX) it is required to be
 914	 * called before cache_bp_init() for setting up MTRR state.
 915	 */
 916	init_hypervisor_platform();
 917
 918	tsc_early_init();
 919	x86_init.resources.probe_roms();
 920
 921	/* after parse_early_param, so could debug it */
 922	insert_resource(&iomem_resource, &code_resource);
 923	insert_resource(&iomem_resource, &rodata_resource);
 924	insert_resource(&iomem_resource, &data_resource);
 925	insert_resource(&iomem_resource, &bss_resource);
 926
 927	e820_add_kernel_range();
 928	trim_bios_range();
 929#ifdef CONFIG_X86_32
 930	if (ppro_with_ram_bug()) {
 931		e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
 932				  E820_TYPE_RESERVED);
 933		e820__update_table(e820_table);
 934		printk(KERN_INFO "fixed physical RAM map:\n");
 935		e820__print_table("bad_ppro");
 936	}
 937#else
 938	early_gart_iommu_check();
 939#endif
 940
 941	/*
 942	 * partially used pages are not usable - thus
 943	 * we are rounding upwards:
 944	 */
 945	max_pfn = e820__end_of_ram_pfn();
 946
 947	/* update e820 for memory not covered by WB MTRRs */
 948	cache_bp_init();
 949	if (mtrr_trim_uncached_memory(max_pfn))
 950		max_pfn = e820__end_of_ram_pfn();
 951
 952	max_possible_pfn = max_pfn;
 953
 954	/*
 
 
 
 
 
 
 
 955	 * Define random base addresses for memory sections after max_pfn is
 956	 * defined and before each memory section base is used.
 957	 */
 958	kernel_randomize_memory();
 959
 960#ifdef CONFIG_X86_32
 961	/* max_low_pfn get updated here */
 962	find_low_pfn_range();
 963#else
 964	check_x2apic();
 965
 966	/* How many end-of-memory variables you have, grandma! */
 967	/* need this before calling reserve_initrd */
 968	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
 969		max_low_pfn = e820__end_of_low_ram_pfn();
 970	else
 971		max_low_pfn = max_pfn;
 972
 973	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 974#endif
 975
 976	/* Find and reserve MPTABLE area */
 977	x86_init.mpparse.find_mptable();
 
 
 978
 979	early_alloc_pgt_buf();
 980
 981	/*
 982	 * Need to conclude brk, before e820__memblock_setup()
 983	 * it could use memblock_find_in_range, could overlap with
 984	 * brk area.
 985	 */
 986	reserve_brk();
 987
 988	cleanup_highmap();
 989
 990	memblock_set_current_limit(ISA_END_ADDRESS);
 991	e820__memblock_setup();
 992
 993	/*
 994	 * Needs to run after memblock setup because it needs the physical
 995	 * memory size.
 996	 */
 997	mem_encrypt_setup_arch();
 998	cc_random_init();
 999
 
1000	efi_find_mirror();
1001	efi_esrt_init();
1002	efi_mokvar_table_init();
1003
1004	/*
1005	 * The EFI specification says that boot service code won't be
1006	 * called after ExitBootServices(). This is, in fact, a lie.
1007	 */
1008	efi_reserve_boot_services();
1009
1010	/* preallocate 4k for mptable mpc */
1011	e820__memblock_alloc_reserved_mpc_new();
1012
1013#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1014	setup_bios_corruption_check();
1015#endif
1016
1017#ifdef CONFIG_X86_32
1018	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1019			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1020#endif
1021
1022	/*
1023	 * Find free memory for the real mode trampoline and place it there. If
1024	 * there is not enough free memory under 1M, on EFI-enabled systems
1025	 * there will be additional attempt to reclaim the memory for the real
1026	 * mode trampoline at efi_free_boot_services().
1027	 *
1028	 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1029	 * are known to corrupt low memory and several hundred kilobytes are not
1030	 * worth complex detection what memory gets clobbered. Windows does the
1031	 * same thing for very similar reasons.
1032	 *
1033	 * Moreover, on machines with SandyBridge graphics or in setups that use
1034	 * crashkernel the entire 1M is reserved anyway.
1035	 *
1036	 * Note the host kernel TDX also requires the first 1MB being reserved.
1037	 */
1038	x86_platform.realmode_reserve();
1039
1040	init_mem_mapping();
1041
1042	/*
1043	 * init_mem_mapping() relies on the early IDT page fault handling.
1044	 * Now either enable FRED or install the real page fault handler
1045	 * for 64-bit in the IDT.
1046	 */
1047	cpu_init_replace_early_idt();
1048
1049	/*
1050	 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1051	 * with the current CR4 value.  This may not be necessary, but
1052	 * auditing all the early-boot CR4 manipulation would be needed to
1053	 * rule it out.
1054	 *
1055	 * Mask off features that don't work outside long mode (just
1056	 * PCIDE for now).
1057	 */
1058	mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1059
1060	memblock_set_current_limit(get_max_mapped());
1061
1062	/*
1063	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1064	 */
1065
1066#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1067	if (init_ohci1394_dma_early)
1068		init_ohci1394_dma_on_all_controllers();
1069#endif
1070	/* Allocate bigger log buffer */
1071	setup_log_buf(1);
1072
1073	if (efi_enabled(EFI_BOOT)) {
1074		switch (boot_params.secure_boot) {
1075		case efi_secureboot_mode_disabled:
1076			pr_info("Secure boot disabled\n");
1077			break;
1078		case efi_secureboot_mode_enabled:
1079			pr_info("Secure boot enabled\n");
1080			break;
1081		default:
1082			pr_info("Secure boot could not be determined\n");
1083			break;
1084		}
1085	}
1086
1087	reserve_initrd();
1088
1089	acpi_table_upgrade();
1090	/* Look for ACPI tables and reserve memory occupied by them. */
1091	acpi_boot_table_init();
1092
1093	vsmp_init();
1094
1095	io_delay_init();
1096
1097	early_platform_quirks();
1098
1099	/* Some platforms need the APIC registered for NUMA configuration */
1100	early_acpi_boot_init();
1101	x86_init.mpparse.early_parse_smp_cfg();
1102
1103	x86_flattree_get_config();
1104
1105	initmem_init();
1106	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1107
1108	if (boot_cpu_has(X86_FEATURE_GBPAGES))
1109		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1110
1111	/*
1112	 * Reserve memory for crash kernel after SRAT is parsed so that it
1113	 * won't consume hotpluggable memory.
1114	 */
1115	arch_reserve_crashkernel();
 
 
1116
1117	if (!early_xdbc_setup_hardware())
1118		early_xdbc_register_console();
1119
1120	x86_init.paging.pagetable_init();
1121
1122	kasan_init();
1123
1124	/*
1125	 * Sync back kernel address range.
1126	 *
1127	 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1128	 * this call?
1129	 */
1130	sync_initial_page_table();
1131
1132	tboot_probe();
1133
1134	map_vsyscall();
1135
1136	x86_32_probe_apic();
1137
1138	early_quirks();
1139
1140	topology_apply_cmdline_limits_early();
1141
1142	/*
1143	 * Parse SMP configuration. Try ACPI first and then the platform
1144	 * specific parser.
1145	 */
1146	acpi_boot_init();
1147	x86_init.mpparse.parse_smp_cfg();
 
 
 
 
 
1148
1149	/* Last opportunity to detect and map the local APIC */
 
 
 
1150	init_apic_mappings();
1151
1152	topology_init_possible_cpus();
1153
1154	init_cpu_to_node();
1155	init_gi_nodes();
1156
1157	io_apic_init_mappings();
1158
1159	x86_init.hyper.guest_late_init();
1160
1161	e820__reserve_resources();
1162	e820__register_nosave_regions(max_pfn);
1163
1164	x86_init.resources.reserve_resources();
1165
1166	e820__setup_pci_gap();
1167
1168#ifdef CONFIG_VT
1169#if defined(CONFIG_VGA_CONSOLE)
1170	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1171		vgacon_register_screen(&screen_info);
1172#endif
1173#endif
1174	x86_init.oem.banner();
1175
1176	x86_init.timers.wallclock_init();
1177
1178	/*
1179	 * This needs to run before setup_local_APIC() which soft-disables the
1180	 * local APIC temporarily and that masks the thermal LVT interrupt,
1181	 * leading to softlockups on machines which have configured SMI
1182	 * interrupt delivery.
1183	 */
1184	therm_lvt_init();
1185
1186	mcheck_init();
1187
1188	register_refined_jiffies(CLOCK_TICK_RATE);
1189
1190#ifdef CONFIG_EFI
1191	if (efi_enabled(EFI_BOOT))
1192		efi_apply_memmap_quirks();
1193#endif
1194
1195	unwind_init();
1196}
1197
1198#ifdef CONFIG_X86_32
1199
1200static struct resource video_ram_resource = {
1201	.name	= "Video RAM area",
1202	.start	= 0xa0000,
1203	.end	= 0xbffff,
1204	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1205};
1206
1207void __init i386_reserve_resources(void)
1208{
1209	request_resource(&iomem_resource, &video_ram_resource);
1210	reserve_standard_io_resources();
1211}
1212
1213#endif /* CONFIG_X86_32 */
1214
1215static struct notifier_block kernel_offset_notifier = {
1216	.notifier_call = dump_kernel_offset
1217};
1218
1219static int __init register_kernel_offset_dumper(void)
1220{
1221	atomic_notifier_chain_register(&panic_notifier_list,
1222					&kernel_offset_notifier);
1223	return 0;
1224}
1225__initcall(register_kernel_offset_dumper);
1226
1227#ifdef CONFIG_HOTPLUG_CPU
1228bool arch_cpu_is_hotpluggable(int cpu)
1229{
1230	return cpu > 0;
1231}
1232#endif /* CONFIG_HOTPLUG_CPU */
v5.14.15
   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/console.h>
 
   9#include <linux/crash_dump.h>
  10#include <linux/dma-map-ops.h>
  11#include <linux/dmi.h>
  12#include <linux/efi.h>
 
  13#include <linux/init_ohci1394_dma.h>
  14#include <linux/initrd.h>
  15#include <linux/iscsi_ibft.h>
  16#include <linux/memblock.h>
  17#include <linux/panic_notifier.h>
  18#include <linux/pci.h>
  19#include <linux/root_dev.h>
  20#include <linux/hugetlb.h>
  21#include <linux/tboot.h>
  22#include <linux/usb/xhci-dbgp.h>
  23#include <linux/static_call.h>
  24#include <linux/swiotlb.h>
 
  25
  26#include <uapi/linux/mount.h>
  27
  28#include <xen/xen.h>
  29
  30#include <asm/apic.h>
 
  31#include <asm/numa.h>
  32#include <asm/bios_ebda.h>
  33#include <asm/bugs.h>
 
 
  34#include <asm/cpu.h>
  35#include <asm/efi.h>
  36#include <asm/gart.h>
  37#include <asm/hypervisor.h>
  38#include <asm/io_apic.h>
  39#include <asm/kasan.h>
  40#include <asm/kaslr.h>
  41#include <asm/mce.h>
 
  42#include <asm/mtrr.h>
  43#include <asm/realmode.h>
  44#include <asm/olpc_ofw.h>
  45#include <asm/pci-direct.h>
  46#include <asm/prom.h>
  47#include <asm/proto.h>
  48#include <asm/thermal.h>
  49#include <asm/unwind.h>
  50#include <asm/vsyscall.h>
  51#include <linux/vmalloc.h>
  52
  53/*
  54 * max_low_pfn_mapped: highest directly mapped pfn < 4 GB
  55 * max_pfn_mapped:     highest directly mapped pfn > 4 GB
  56 *
  57 * The direct mapping only covers E820_TYPE_RAM regions, so the ranges and gaps are
  58 * represented by pfn_mapped[].
  59 */
  60unsigned long max_low_pfn_mapped;
  61unsigned long max_pfn_mapped;
  62
  63#ifdef CONFIG_DMI
  64RESERVE_BRK(dmi_alloc, 65536);
  65#endif
  66
  67
  68/*
  69 * Range of the BSS area. The size of the BSS area is determined
  70 * at link time, with RESERVE_BRK() facility reserving additional
  71 * chunks.
  72 */
  73unsigned long _brk_start = (unsigned long)__brk_base;
  74unsigned long _brk_end   = (unsigned long)__brk_base;
  75
  76struct boot_params boot_params;
  77
  78/*
  79 * These are the four main kernel memory regions, we put them into
  80 * the resource tree so that kdump tools and other debugging tools
  81 * recover it:
  82 */
  83
  84static struct resource rodata_resource = {
  85	.name	= "Kernel rodata",
  86	.start	= 0,
  87	.end	= 0,
  88	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
  89};
  90
  91static struct resource data_resource = {
  92	.name	= "Kernel data",
  93	.start	= 0,
  94	.end	= 0,
  95	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
  96};
  97
  98static struct resource code_resource = {
  99	.name	= "Kernel code",
 100	.start	= 0,
 101	.end	= 0,
 102	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
 103};
 104
 105static struct resource bss_resource = {
 106	.name	= "Kernel bss",
 107	.start	= 0,
 108	.end	= 0,
 109	.flags	= IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM
 110};
 111
 112
 113#ifdef CONFIG_X86_32
 114/* CPU data as detected by the assembly code in head_32.S */
 115struct cpuinfo_x86 new_cpu_data;
 116
 117/* Common CPU data for all CPUs */
 118struct cpuinfo_x86 boot_cpu_data __read_mostly;
 119EXPORT_SYMBOL(boot_cpu_data);
 120
 121unsigned int def_to_bigsmp;
 122
 123struct apm_info apm_info;
 124EXPORT_SYMBOL(apm_info);
 125
 126#if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
 127	defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
 128struct ist_info ist_info;
 129EXPORT_SYMBOL(ist_info);
 130#else
 131struct ist_info ist_info;
 132#endif
 133
 134#else
 
 135struct cpuinfo_x86 boot_cpu_data __read_mostly;
 136EXPORT_SYMBOL(boot_cpu_data);
 137#endif
 138
 139
 140#if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
 141__visible unsigned long mmu_cr4_features __ro_after_init;
 142#else
 143__visible unsigned long mmu_cr4_features __ro_after_init = X86_CR4_PAE;
 144#endif
 145
 
 
 
 
 
 146/* Boot loader ID and version as integers, for the benefit of proc_dointvec */
 147int bootloader_type, bootloader_version;
 148
 149/*
 150 * Setup options
 151 */
 152struct screen_info screen_info;
 153EXPORT_SYMBOL(screen_info);
 154struct edid_info edid_info;
 155EXPORT_SYMBOL_GPL(edid_info);
 156
 157extern int root_mountflags;
 158
 159unsigned long saved_video_mode;
 160
 161#define RAMDISK_IMAGE_START_MASK	0x07FF
 162#define RAMDISK_PROMPT_FLAG		0x8000
 163#define RAMDISK_LOAD_FLAG		0x4000
 164
 165static char __initdata command_line[COMMAND_LINE_SIZE];
 166#ifdef CONFIG_CMDLINE_BOOL
 167static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE;
 
 168#endif
 169
 170#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 171struct edd edd;
 172#ifdef CONFIG_EDD_MODULE
 173EXPORT_SYMBOL(edd);
 174#endif
 175/**
 176 * copy_edd() - Copy the BIOS EDD information
 177 *              from boot_params into a safe place.
 178 *
 179 */
 180static inline void __init copy_edd(void)
 181{
 182     memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
 183	    sizeof(edd.mbr_signature));
 184     memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
 185     edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
 186     edd.edd_info_nr = boot_params.eddbuf_entries;
 187}
 188#else
 189static inline void __init copy_edd(void)
 190{
 191}
 192#endif
 193
 194void * __init extend_brk(size_t size, size_t align)
 195{
 196	size_t mask = align - 1;
 197	void *ret;
 198
 199	BUG_ON(_brk_start == 0);
 200	BUG_ON(align & mask);
 201
 202	_brk_end = (_brk_end + mask) & ~mask;
 203	BUG_ON((char *)(_brk_end + size) > __brk_limit);
 204
 205	ret = (void *)_brk_end;
 206	_brk_end += size;
 207
 208	memset(ret, 0, size);
 209
 210	return ret;
 211}
 212
 213#ifdef CONFIG_X86_32
 214static void __init cleanup_highmap(void)
 215{
 216}
 217#endif
 218
 219static void __init reserve_brk(void)
 220{
 221	if (_brk_end > _brk_start)
 222		memblock_reserve(__pa_symbol(_brk_start),
 223				 _brk_end - _brk_start);
 224
 225	/* Mark brk area as locked down and no longer taking any
 226	   new allocations */
 227	_brk_start = 0;
 228}
 229
 230u64 relocated_ramdisk;
 231
 232#ifdef CONFIG_BLK_DEV_INITRD
 233
 234static u64 __init get_ramdisk_image(void)
 235{
 236	u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 237
 238	ramdisk_image |= (u64)boot_params.ext_ramdisk_image << 32;
 239
 240	if (ramdisk_image == 0)
 241		ramdisk_image = phys_initrd_start;
 242
 243	return ramdisk_image;
 244}
 245static u64 __init get_ramdisk_size(void)
 246{
 247	u64 ramdisk_size = boot_params.hdr.ramdisk_size;
 248
 249	ramdisk_size |= (u64)boot_params.ext_ramdisk_size << 32;
 250
 251	if (ramdisk_size == 0)
 252		ramdisk_size = phys_initrd_size;
 253
 254	return ramdisk_size;
 255}
 256
 257static void __init relocate_initrd(void)
 258{
 259	/* Assume only end is not page aligned */
 260	u64 ramdisk_image = get_ramdisk_image();
 261	u64 ramdisk_size  = get_ramdisk_size();
 262	u64 area_size     = PAGE_ALIGN(ramdisk_size);
 263
 264	/* We need to move the initrd down into directly mapped mem */
 265	relocated_ramdisk = memblock_phys_alloc_range(area_size, PAGE_SIZE, 0,
 266						      PFN_PHYS(max_pfn_mapped));
 267	if (!relocated_ramdisk)
 268		panic("Cannot find place for new RAMDISK of size %lld\n",
 269		      ramdisk_size);
 270
 271	initrd_start = relocated_ramdisk + PAGE_OFFSET;
 272	initrd_end   = initrd_start + ramdisk_size;
 273	printk(KERN_INFO "Allocated new RAMDISK: [mem %#010llx-%#010llx]\n",
 274	       relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
 275
 276	copy_from_early_mem((void *)initrd_start, ramdisk_image, ramdisk_size);
 277
 278	printk(KERN_INFO "Move RAMDISK from [mem %#010llx-%#010llx] to"
 279		" [mem %#010llx-%#010llx]\n",
 280		ramdisk_image, ramdisk_image + ramdisk_size - 1,
 281		relocated_ramdisk, relocated_ramdisk + ramdisk_size - 1);
 282}
 283
 284static void __init early_reserve_initrd(void)
 285{
 286	/* Assume only end is not page aligned */
 287	u64 ramdisk_image = get_ramdisk_image();
 288	u64 ramdisk_size  = get_ramdisk_size();
 289	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
 290
 291	if (!boot_params.hdr.type_of_loader ||
 292	    !ramdisk_image || !ramdisk_size)
 293		return;		/* No initrd provided by bootloader */
 294
 295	memblock_reserve(ramdisk_image, ramdisk_end - ramdisk_image);
 296}
 297
 298static void __init reserve_initrd(void)
 299{
 300	/* Assume only end is not page aligned */
 301	u64 ramdisk_image = get_ramdisk_image();
 302	u64 ramdisk_size  = get_ramdisk_size();
 303	u64 ramdisk_end   = PAGE_ALIGN(ramdisk_image + ramdisk_size);
 304
 305	if (!boot_params.hdr.type_of_loader ||
 306	    !ramdisk_image || !ramdisk_size)
 307		return;		/* No initrd provided by bootloader */
 308
 309	initrd_start = 0;
 310
 311	printk(KERN_INFO "RAMDISK: [mem %#010llx-%#010llx]\n", ramdisk_image,
 312			ramdisk_end - 1);
 313
 314	if (pfn_range_is_mapped(PFN_DOWN(ramdisk_image),
 315				PFN_DOWN(ramdisk_end))) {
 316		/* All are mapped, easy case */
 317		initrd_start = ramdisk_image + PAGE_OFFSET;
 318		initrd_end = initrd_start + ramdisk_size;
 319		return;
 320	}
 321
 322	relocate_initrd();
 323
 324	memblock_free(ramdisk_image, ramdisk_end - ramdisk_image);
 325}
 326
 327#else
 328static void __init early_reserve_initrd(void)
 329{
 330}
 331static void __init reserve_initrd(void)
 332{
 333}
 334#endif /* CONFIG_BLK_DEV_INITRD */
 335
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 336static void __init parse_setup_data(void)
 337{
 338	struct setup_data *data;
 339	u64 pa_data, pa_next;
 340
 341	pa_data = boot_params.hdr.setup_data;
 342	while (pa_data) {
 343		u32 data_len, data_type;
 344
 345		data = early_memremap(pa_data, sizeof(*data));
 346		data_len = data->len + sizeof(struct setup_data);
 347		data_type = data->type;
 348		pa_next = data->next;
 349		early_memunmap(data, sizeof(*data));
 350
 351		switch (data_type) {
 352		case SETUP_E820_EXT:
 353			e820__memory_setup_extended(pa_data, data_len);
 354			break;
 355		case SETUP_DTB:
 356			add_dtb(pa_data);
 357			break;
 358		case SETUP_EFI:
 359			parse_efi_setup(pa_data, data_len);
 360			break;
 
 
 
 
 
 
 
 
 
 
 
 
 361		default:
 362			break;
 363		}
 364		pa_data = pa_next;
 365	}
 366}
 367
 368static void __init memblock_x86_reserve_range_setup_data(void)
 369{
 
 370	struct setup_data *data;
 371	u64 pa_data;
 
 372
 373	pa_data = boot_params.hdr.setup_data;
 374	while (pa_data) {
 375		data = early_memremap(pa_data, sizeof(*data));
 376		memblock_reserve(pa_data, sizeof(*data) + data->len);
 
 
 
 377
 378		if (data->type == SETUP_INDIRECT &&
 379		    ((struct setup_indirect *)data->data)->type != SETUP_INDIRECT)
 380			memblock_reserve(((struct setup_indirect *)data->data)->addr,
 381					 ((struct setup_indirect *)data->data)->len);
 382
 383		pa_data = data->next;
 384		early_memunmap(data, sizeof(*data));
 385	}
 386}
 387
 388/*
 389 * --------- Crashkernel reservation ------------------------------
 390 */
 
 
 
 
 
 391
 392#ifdef CONFIG_KEXEC_CORE
 393
 394/* 16M alignment for crash kernel regions */
 395#define CRASH_ALIGN		SZ_16M
 
 396
 397/*
 398 * Keep the crash kernel below this limit.
 399 *
 400 * Earlier 32-bits kernels would limit the kernel to the low 512 MB range
 401 * due to mapping restrictions.
 402 *
 403 * 64-bit kdump kernels need to be restricted to be under 64 TB, which is
 404 * the upper limit of system RAM in 4-level paging mode. Since the kdump
 405 * jump could be from 5-level paging to 4-level paging, the jump will fail if
 406 * the kernel is put above 64 TB, and during the 1st kernel bootup there's
 407 * no good way to detect the paging mode of the target kernel which will be
 408 * loaded for dumping.
 409 */
 410#ifdef CONFIG_X86_32
 411# define CRASH_ADDR_LOW_MAX	SZ_512M
 412# define CRASH_ADDR_HIGH_MAX	SZ_512M
 413#else
 414# define CRASH_ADDR_LOW_MAX	SZ_4G
 415# define CRASH_ADDR_HIGH_MAX	SZ_64T
 416#endif
 417
 418static int __init reserve_crashkernel_low(void)
 419{
 420#ifdef CONFIG_X86_64
 421	unsigned long long base, low_base = 0, low_size = 0;
 422	unsigned long low_mem_limit;
 423	int ret;
 424
 425	low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
 426
 427	/* crashkernel=Y,low */
 428	ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base);
 429	if (ret) {
 430		/*
 431		 * two parts from kernel/dma/swiotlb.c:
 432		 * -swiotlb size: user-specified with swiotlb= or default.
 433		 *
 434		 * -swiotlb overflow buffer: now hardcoded to 32k. We round it
 435		 * to 8M for other buffers that may need to stay low too. Also
 436		 * make sure we allocate enough extra low memory so that we
 437		 * don't run out of DMA buffers for 32-bit devices.
 438		 */
 439		low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20);
 440	} else {
 441		/* passed with crashkernel=0,low ? */
 442		if (!low_size)
 443			return 0;
 444	}
 445
 446	low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
 447	if (!low_base) {
 448		pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
 449		       (unsigned long)(low_size >> 20));
 450		return -ENOMEM;
 451	}
 452
 453	pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
 454		(unsigned long)(low_size >> 20),
 455		(unsigned long)(low_base >> 20),
 456		(unsigned long)(low_mem_limit >> 20));
 457
 458	crashk_low_res.start = low_base;
 459	crashk_low_res.end   = low_base + low_size - 1;
 460	insert_resource(&iomem_resource, &crashk_low_res);
 461#endif
 462	return 0;
 463}
 464
 465static void __init reserve_crashkernel(void)
 466{
 467	unsigned long long crash_size, crash_base, total_mem;
 
 468	bool high = false;
 469	int ret;
 470
 471	total_mem = memblock_phys_mem_size();
 
 472
 473	/* crashkernel=XM */
 474	ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base);
 475	if (ret != 0 || crash_size <= 0) {
 476		/* crashkernel=X,high */
 477		ret = parse_crashkernel_high(boot_command_line, total_mem,
 478					     &crash_size, &crash_base);
 479		if (ret != 0 || crash_size <= 0)
 480			return;
 481		high = true;
 482	}
 483
 484	if (xen_pv_domain()) {
 485		pr_info("Ignoring crashkernel for a Xen PV domain\n");
 486		return;
 487	}
 488
 489	/* 0 means: find the address automatically */
 490	if (!crash_base) {
 491		/*
 492		 * Set CRASH_ADDR_LOW_MAX upper bound for crash memory,
 493		 * crashkernel=x,high reserves memory over 4G, also allocates
 494		 * 256M extra low memory for DMA buffers and swiotlb.
 495		 * But the extra memory is not required for all machines.
 496		 * So try low memory first and fall back to high memory
 497		 * unless "crashkernel=size[KMG],high" is specified.
 498		 */
 499		if (!high)
 500			crash_base = memblock_phys_alloc_range(crash_size,
 501						CRASH_ALIGN, CRASH_ALIGN,
 502						CRASH_ADDR_LOW_MAX);
 503		if (!crash_base)
 504			crash_base = memblock_phys_alloc_range(crash_size,
 505						CRASH_ALIGN, CRASH_ALIGN,
 506						CRASH_ADDR_HIGH_MAX);
 507		if (!crash_base) {
 508			pr_info("crashkernel reservation failed - No suitable area found.\n");
 509			return;
 510		}
 511	} else {
 512		unsigned long long start;
 513
 514		start = memblock_phys_alloc_range(crash_size, SZ_1M, crash_base,
 515						  crash_base + crash_size);
 516		if (start != crash_base) {
 517			pr_info("crashkernel reservation failed - memory is in use.\n");
 518			return;
 519		}
 520	}
 521
 522	if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) {
 523		memblock_free(crash_base, crash_size);
 524		return;
 525	}
 526
 527	pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
 528		(unsigned long)(crash_size >> 20),
 529		(unsigned long)(crash_base >> 20),
 530		(unsigned long)(total_mem >> 20));
 531
 532	crashk_res.start = crash_base;
 533	crashk_res.end   = crash_base + crash_size - 1;
 534	insert_resource(&iomem_resource, &crashk_res);
 535}
 536#else
 537static void __init reserve_crashkernel(void)
 538{
 539}
 540#endif
 541
 542static struct resource standard_io_resources[] = {
 543	{ .name = "dma1", .start = 0x00, .end = 0x1f,
 544		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 545	{ .name = "pic1", .start = 0x20, .end = 0x21,
 546		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 547	{ .name = "timer0", .start = 0x40, .end = 0x43,
 548		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 549	{ .name = "timer1", .start = 0x50, .end = 0x53,
 550		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 551	{ .name = "keyboard", .start = 0x60, .end = 0x60,
 552		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 553	{ .name = "keyboard", .start = 0x64, .end = 0x64,
 554		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 555	{ .name = "dma page reg", .start = 0x80, .end = 0x8f,
 556		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 557	{ .name = "pic2", .start = 0xa0, .end = 0xa1,
 558		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 559	{ .name = "dma2", .start = 0xc0, .end = 0xdf,
 560		.flags = IORESOURCE_BUSY | IORESOURCE_IO },
 561	{ .name = "fpu", .start = 0xf0, .end = 0xff,
 562		.flags = IORESOURCE_BUSY | IORESOURCE_IO }
 563};
 564
 565void __init reserve_standard_io_resources(void)
 566{
 567	int i;
 568
 569	/* request I/O space for devices used on all i[345]86 PCs */
 570	for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
 571		request_resource(&ioport_resource, &standard_io_resources[i]);
 572
 573}
 574
 575static __init void reserve_ibft_region(void)
 576{
 577	unsigned long addr, size = 0;
 578
 579	addr = find_ibft_region(&size);
 580
 581	if (size)
 582		memblock_reserve(addr, size);
 583}
 584
 585static bool __init snb_gfx_workaround_needed(void)
 586{
 587#ifdef CONFIG_PCI
 588	int i;
 589	u16 vendor, devid;
 590	static const __initconst u16 snb_ids[] = {
 591		0x0102,
 592		0x0112,
 593		0x0122,
 594		0x0106,
 595		0x0116,
 596		0x0126,
 597		0x010a,
 598	};
 599
 600	/* Assume no if something weird is going on with PCI */
 601	if (!early_pci_allowed())
 602		return false;
 603
 604	vendor = read_pci_config_16(0, 2, 0, PCI_VENDOR_ID);
 605	if (vendor != 0x8086)
 606		return false;
 607
 608	devid = read_pci_config_16(0, 2, 0, PCI_DEVICE_ID);
 609	for (i = 0; i < ARRAY_SIZE(snb_ids); i++)
 610		if (devid == snb_ids[i])
 611			return true;
 612#endif
 613
 614	return false;
 615}
 616
 617/*
 618 * Sandy Bridge graphics has trouble with certain ranges, exclude
 619 * them from allocation.
 620 */
 621static void __init trim_snb_memory(void)
 622{
 623	static const __initconst unsigned long bad_pages[] = {
 624		0x20050000,
 625		0x20110000,
 626		0x20130000,
 627		0x20138000,
 628		0x40004000,
 629	};
 630	int i;
 631
 632	if (!snb_gfx_workaround_needed())
 633		return;
 634
 635	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
 636
 637	/*
 638	 * SandyBridge integrated graphics devices have a bug that prevents
 639	 * them from accessing certain memory ranges, namely anything below
 640	 * 1M and in the pages listed in bad_pages[] above.
 641	 *
 642	 * To avoid these pages being ever accessed by SNB gfx devices reserve
 643	 * bad_pages that have not already been reserved at boot time.
 644	 * All memory below the 1 MB mark is anyway reserved later during
 645	 * setup_arch(), so there is no need to reserve it here.
 646	 */
 647
 648	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
 649		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
 650			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
 651			       bad_pages[i]);
 652	}
 653}
 654
 655static void __init trim_bios_range(void)
 656{
 657	/*
 658	 * A special case is the first 4Kb of memory;
 659	 * This is a BIOS owned area, not kernel ram, but generally
 660	 * not listed as such in the E820 table.
 661	 *
 662	 * This typically reserves additional memory (64KiB by default)
 663	 * since some BIOSes are known to corrupt low memory.  See the
 664	 * Kconfig help text for X86_RESERVE_LOW.
 665	 */
 666	e820__range_update(0, PAGE_SIZE, E820_TYPE_RAM, E820_TYPE_RESERVED);
 667
 668	/*
 669	 * special case: Some BIOSes report the PC BIOS
 670	 * area (640Kb -> 1Mb) as RAM even though it is not.
 671	 * take them out.
 672	 */
 673	e820__range_remove(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_TYPE_RAM, 1);
 674
 675	e820__update_table(e820_table);
 676}
 677
 678/* called before trim_bios_range() to spare extra sanitize */
 679static void __init e820_add_kernel_range(void)
 680{
 681	u64 start = __pa_symbol(_text);
 682	u64 size = __pa_symbol(_end) - start;
 683
 684	/*
 685	 * Complain if .text .data and .bss are not marked as E820_TYPE_RAM and
 686	 * attempt to fix it by adding the range. We may have a confused BIOS,
 687	 * or the user may have used memmap=exactmap or memmap=xxM$yyM to
 688	 * exclude kernel range. If we really are running on top non-RAM,
 689	 * we will crash later anyways.
 690	 */
 691	if (e820__mapped_all(start, start + size, E820_TYPE_RAM))
 692		return;
 693
 694	pr_warn(".text .data .bss are not marked as E820_TYPE_RAM!\n");
 695	e820__range_remove(start, size, E820_TYPE_RAM, 0);
 696	e820__range_add(start, size, E820_TYPE_RAM);
 697}
 698
 699static void __init early_reserve_memory(void)
 700{
 701	/*
 702	 * Reserve the memory occupied by the kernel between _text and
 703	 * __end_of_kernel_reserve symbols. Any kernel sections after the
 704	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
 705	 * separate memblock_reserve() or they will be discarded.
 706	 */
 707	memblock_reserve(__pa_symbol(_text),
 708			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
 709
 710	/*
 711	 * The first 4Kb of memory is a BIOS owned area, but generally it is
 712	 * not listed as such in the E820 table.
 713	 *
 714	 * Reserve the first 64K of memory since some BIOSes are known to
 715	 * corrupt low memory. After the real mode trampoline is allocated the
 716	 * rest of the memory below 640k is reserved.
 717	 *
 718	 * In addition, make sure page 0 is always reserved because on
 719	 * systems with L1TF its contents can be leaked to user processes.
 720	 */
 721	memblock_reserve(0, SZ_64K);
 722
 723	early_reserve_initrd();
 724
 725	if (efi_enabled(EFI_BOOT))
 726		efi_memblock_x86_reserve_range();
 727
 728	memblock_x86_reserve_range_setup_data();
 729
 730	reserve_ibft_region();
 731	reserve_bios_regions();
 732	trim_snb_memory();
 733}
 734
 735/*
 736 * Dump out kernel offset information on panic.
 737 */
 738static int
 739dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
 740{
 741	if (kaslr_enabled()) {
 742		pr_emerg("Kernel Offset: 0x%lx from 0x%lx (relocation range: 0x%lx-0x%lx)\n",
 743			 kaslr_offset(),
 744			 __START_KERNEL,
 745			 __START_KERNEL_map,
 746			 MODULES_VADDR-1);
 747	} else {
 748		pr_emerg("Kernel Offset: disabled\n");
 749	}
 750
 751	return 0;
 752}
 753
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 754/*
 755 * Determine if we were loaded by an EFI loader.  If so, then we have also been
 756 * passed the efi memmap, systab, etc., so we should use these data structures
 757 * for initialization.  Note, the efi init code path is determined by the
 758 * global efi_enabled. This allows the same kernel image to be used on existing
 759 * systems (with a traditional BIOS) as well as on EFI systems.
 760 */
 761/*
 762 * setup_arch - architecture-specific boot-time initializations
 763 *
 764 * Note: On x86_64, fixmaps are ready for use even before this is called.
 765 */
 766
 767void __init setup_arch(char **cmdline_p)
 768{
 769#ifdef CONFIG_X86_32
 770	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
 771
 772	/*
 773	 * copy kernel address range established so far and switch
 774	 * to the proper swapper page table
 775	 */
 776	clone_pgd_range(swapper_pg_dir     + KERNEL_PGD_BOUNDARY,
 777			initial_page_table + KERNEL_PGD_BOUNDARY,
 778			KERNEL_PGD_PTRS);
 779
 780	load_cr3(swapper_pg_dir);
 781	/*
 782	 * Note: Quark X1000 CPUs advertise PGE incorrectly and require
 783	 * a cr3 based tlb flush, so the following __flush_tlb_all()
 784	 * will not flush anything because the CPU quirk which clears
 785	 * X86_FEATURE_PGE has not been invoked yet. Though due to the
 786	 * load_cr3() above the TLB has been flushed already. The
 787	 * quirk is invoked before subsequent calls to __flush_tlb_all()
 788	 * so proper operation is guaranteed.
 789	 */
 790	__flush_tlb_all();
 791#else
 792	printk(KERN_INFO "Command line: %s\n", boot_command_line);
 793	boot_cpu_data.x86_phys_bits = MAX_PHYSMEM_BITS;
 794#endif
 795
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 796	/*
 797	 * If we have OLPC OFW, we might end up relocating the fixmap due to
 798	 * reserve_top(), so do this before touching the ioremap area.
 799	 */
 800	olpc_ofw_detect();
 801
 802	idt_setup_early_traps();
 803	early_cpu_init();
 804	jump_label_init();
 805	static_call_init();
 806	early_ioremap_init();
 807
 808	setup_olpc_ofw_pgd();
 809
 810	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
 811	screen_info = boot_params.screen_info;
 812	edid_info = boot_params.edid_info;
 813#ifdef CONFIG_X86_32
 814	apm_info.bios = boot_params.apm_bios_info;
 815	ist_info = boot_params.ist_info;
 816#endif
 817	saved_video_mode = boot_params.hdr.vid_mode;
 818	bootloader_type = boot_params.hdr.type_of_loader;
 819	if ((bootloader_type >> 4) == 0xe) {
 820		bootloader_type &= 0xf;
 821		bootloader_type |= (boot_params.hdr.ext_loader_type+0x10) << 4;
 822	}
 823	bootloader_version  = bootloader_type & 0xf;
 824	bootloader_version |= boot_params.hdr.ext_loader_ver << 4;
 825
 826#ifdef CONFIG_BLK_DEV_RAM
 827	rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
 828#endif
 829#ifdef CONFIG_EFI
 830	if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
 831		     EFI32_LOADER_SIGNATURE, 4)) {
 832		set_bit(EFI_BOOT, &efi.flags);
 833	} else if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
 834		     EFI64_LOADER_SIGNATURE, 4)) {
 835		set_bit(EFI_BOOT, &efi.flags);
 836		set_bit(EFI_64BIT, &efi.flags);
 837	}
 838#endif
 839
 840	x86_init.oem.arch_setup();
 841
 842	/*
 843	 * Do some memory reservations *before* memory is added to memblock, so
 844	 * memblock allocations won't overwrite it.
 845	 *
 846	 * After this point, everything still needed from the boot loader or
 847	 * firmware or kernel text should be early reserved or marked not RAM in
 848	 * e820. All other memory is free game.
 849	 *
 850	 * This call needs to happen before e820__memory_setup() which calls the
 851	 * xen_memory_setup() on Xen dom0 which relies on the fact that those
 852	 * early reservations have happened already.
 853	 */
 854	early_reserve_memory();
 855
 856	iomem_resource.end = (1ULL << boot_cpu_data.x86_phys_bits) - 1;
 857	e820__memory_setup();
 858	parse_setup_data();
 859
 860	copy_edd();
 861
 862	if (!boot_params.hdr.root_flags)
 863		root_mountflags &= ~MS_RDONLY;
 864	setup_initial_init_mm(_text, _etext, _edata, (void *)_brk_end);
 865
 866	code_resource.start = __pa_symbol(_text);
 867	code_resource.end = __pa_symbol(_etext)-1;
 868	rodata_resource.start = __pa_symbol(__start_rodata);
 869	rodata_resource.end = __pa_symbol(__end_rodata)-1;
 870	data_resource.start = __pa_symbol(_sdata);
 871	data_resource.end = __pa_symbol(_edata)-1;
 872	bss_resource.start = __pa_symbol(__bss_start);
 873	bss_resource.end = __pa_symbol(__bss_stop)-1;
 874
 875#ifdef CONFIG_CMDLINE_BOOL
 876#ifdef CONFIG_CMDLINE_OVERRIDE
 877	strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
 878#else
 879	if (builtin_cmdline[0]) {
 880		/* append boot loader cmdline to builtin */
 881		strlcat(builtin_cmdline, " ", COMMAND_LINE_SIZE);
 882		strlcat(builtin_cmdline, boot_command_line, COMMAND_LINE_SIZE);
 883		strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
 884	}
 885#endif
 886#endif
 887
 888	strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
 889	*cmdline_p = command_line;
 890
 891	/*
 892	 * x86_configure_nx() is called before parse_early_param() to detect
 893	 * whether hardware doesn't support NX (so that the early EHCI debug
 894	 * console setup can safely call set_fixmap()). It may then be called
 895	 * again from within noexec_setup() during parsing early parameters
 896	 * to honor the respective command line option.
 897	 */
 898	x86_configure_nx();
 899
 900	parse_early_param();
 901
 
 
 
 902#ifdef CONFIG_MEMORY_HOTPLUG
 903	/*
 904	 * Memory used by the kernel cannot be hot-removed because Linux
 905	 * cannot migrate the kernel pages. When memory hotplug is
 906	 * enabled, we should prevent memblock from allocating memory
 907	 * for the kernel.
 908	 *
 909	 * ACPI SRAT records all hotpluggable memory ranges. But before
 910	 * SRAT is parsed, we don't know about it.
 911	 *
 912	 * The kernel image is loaded into memory at very early time. We
 913	 * cannot prevent this anyway. So on NUMA system, we set any
 914	 * node the kernel resides in as un-hotpluggable.
 915	 *
 916	 * Since on modern servers, one node could have double-digit
 917	 * gigabytes memory, we can assume the memory around the kernel
 918	 * image is also un-hotpluggable. So before SRAT is parsed, just
 919	 * allocate memory near the kernel image to try the best to keep
 920	 * the kernel away from hotpluggable memory.
 921	 */
 922	if (movable_node_is_enabled())
 923		memblock_set_bottom_up(true);
 924#endif
 925
 926	x86_report_nx();
 927
 
 
 928	if (acpi_mps_check()) {
 929#ifdef CONFIG_X86_LOCAL_APIC
 930		disable_apic = 1;
 931#endif
 932		setup_clear_cpu_cap(X86_FEATURE_APIC);
 933	}
 934
 935	e820__reserve_setup_data();
 936	e820__finish_early_params();
 937
 938	if (efi_enabled(EFI_BOOT))
 939		efi_init();
 940
 941	dmi_setup();
 
 942
 943	/*
 944	 * VMware detection requires dmi to be available, so this
 945	 * needs to be done after dmi_setup(), for the boot CPU.
 
 
 946	 */
 947	init_hypervisor_platform();
 948
 949	tsc_early_init();
 950	x86_init.resources.probe_roms();
 951
 952	/* after parse_early_param, so could debug it */
 953	insert_resource(&iomem_resource, &code_resource);
 954	insert_resource(&iomem_resource, &rodata_resource);
 955	insert_resource(&iomem_resource, &data_resource);
 956	insert_resource(&iomem_resource, &bss_resource);
 957
 958	e820_add_kernel_range();
 959	trim_bios_range();
 960#ifdef CONFIG_X86_32
 961	if (ppro_with_ram_bug()) {
 962		e820__range_update(0x70000000ULL, 0x40000ULL, E820_TYPE_RAM,
 963				  E820_TYPE_RESERVED);
 964		e820__update_table(e820_table);
 965		printk(KERN_INFO "fixed physical RAM map:\n");
 966		e820__print_table("bad_ppro");
 967	}
 968#else
 969	early_gart_iommu_check();
 970#endif
 971
 972	/*
 973	 * partially used pages are not usable - thus
 974	 * we are rounding upwards:
 975	 */
 976	max_pfn = e820__end_of_ram_pfn();
 977
 978	/* update e820 for memory not covered by WB MTRRs */
 979	mtrr_bp_init();
 980	if (mtrr_trim_uncached_memory(max_pfn))
 981		max_pfn = e820__end_of_ram_pfn();
 982
 983	max_possible_pfn = max_pfn;
 984
 985	/*
 986	 * This call is required when the CPU does not support PAT. If
 987	 * mtrr_bp_init() invoked it already via pat_init() the call has no
 988	 * effect.
 989	 */
 990	init_cache_modes();
 991
 992	/*
 993	 * Define random base addresses for memory sections after max_pfn is
 994	 * defined and before each memory section base is used.
 995	 */
 996	kernel_randomize_memory();
 997
 998#ifdef CONFIG_X86_32
 999	/* max_low_pfn get updated here */
1000	find_low_pfn_range();
1001#else
1002	check_x2apic();
1003
1004	/* How many end-of-memory variables you have, grandma! */
1005	/* need this before calling reserve_initrd */
1006	if (max_pfn > (1UL<<(32 - PAGE_SHIFT)))
1007		max_low_pfn = e820__end_of_low_ram_pfn();
1008	else
1009		max_low_pfn = max_pfn;
1010
1011	high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
1012#endif
1013
1014	/*
1015	 * Find and reserve possible boot-time SMP configuration:
1016	 */
1017	find_smp_config();
1018
1019	early_alloc_pgt_buf();
1020
1021	/*
1022	 * Need to conclude brk, before e820__memblock_setup()
1023	 * it could use memblock_find_in_range, could overlap with
1024	 * brk area.
1025	 */
1026	reserve_brk();
1027
1028	cleanup_highmap();
1029
1030	memblock_set_current_limit(ISA_END_ADDRESS);
1031	e820__memblock_setup();
1032
1033	/*
1034	 * Needs to run after memblock setup because it needs the physical
1035	 * memory size.
1036	 */
1037	sev_setup_arch();
 
1038
1039	efi_fake_memmap();
1040	efi_find_mirror();
1041	efi_esrt_init();
1042	efi_mokvar_table_init();
1043
1044	/*
1045	 * The EFI specification says that boot service code won't be
1046	 * called after ExitBootServices(). This is, in fact, a lie.
1047	 */
1048	efi_reserve_boot_services();
1049
1050	/* preallocate 4k for mptable mpc */
1051	e820__memblock_alloc_reserved_mpc_new();
1052
1053#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
1054	setup_bios_corruption_check();
1055#endif
1056
1057#ifdef CONFIG_X86_32
1058	printk(KERN_DEBUG "initial memory mapped: [mem 0x00000000-%#010lx]\n",
1059			(max_pfn_mapped<<PAGE_SHIFT) - 1);
1060#endif
1061
1062	/*
1063	 * Find free memory for the real mode trampoline and place it there. If
1064	 * there is not enough free memory under 1M, on EFI-enabled systems
1065	 * there will be additional attempt to reclaim the memory for the real
1066	 * mode trampoline at efi_free_boot_services().
1067	 *
1068	 * Unconditionally reserve the entire first 1M of RAM because BIOSes
1069	 * are known to corrupt low memory and several hundred kilobytes are not
1070	 * worth complex detection what memory gets clobbered. Windows does the
1071	 * same thing for very similar reasons.
1072	 *
1073	 * Moreover, on machines with SandyBridge graphics or in setups that use
1074	 * crashkernel the entire 1M is reserved anyway.
 
 
1075	 */
1076	reserve_real_mode();
1077
1078	init_mem_mapping();
1079
1080	idt_setup_early_pf();
 
 
 
 
 
1081
1082	/*
1083	 * Update mmu_cr4_features (and, indirectly, trampoline_cr4_features)
1084	 * with the current CR4 value.  This may not be necessary, but
1085	 * auditing all the early-boot CR4 manipulation would be needed to
1086	 * rule it out.
1087	 *
1088	 * Mask off features that don't work outside long mode (just
1089	 * PCIDE for now).
1090	 */
1091	mmu_cr4_features = __read_cr4() & ~X86_CR4_PCIDE;
1092
1093	memblock_set_current_limit(get_max_mapped());
1094
1095	/*
1096	 * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
1097	 */
1098
1099#ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
1100	if (init_ohci1394_dma_early)
1101		init_ohci1394_dma_on_all_controllers();
1102#endif
1103	/* Allocate bigger log buffer */
1104	setup_log_buf(1);
1105
1106	if (efi_enabled(EFI_BOOT)) {
1107		switch (boot_params.secure_boot) {
1108		case efi_secureboot_mode_disabled:
1109			pr_info("Secure boot disabled\n");
1110			break;
1111		case efi_secureboot_mode_enabled:
1112			pr_info("Secure boot enabled\n");
1113			break;
1114		default:
1115			pr_info("Secure boot could not be determined\n");
1116			break;
1117		}
1118	}
1119
1120	reserve_initrd();
1121
1122	acpi_table_upgrade();
1123	/* Look for ACPI tables and reserve memory occupied by them. */
1124	acpi_boot_table_init();
1125
1126	vsmp_init();
1127
1128	io_delay_init();
1129
1130	early_platform_quirks();
1131
 
1132	early_acpi_boot_init();
 
 
 
1133
1134	initmem_init();
1135	dma_contiguous_reserve(max_pfn_mapped << PAGE_SHIFT);
1136
1137	if (boot_cpu_has(X86_FEATURE_GBPAGES))
1138		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
1139
1140	/*
1141	 * Reserve memory for crash kernel after SRAT is parsed so that it
1142	 * won't consume hotpluggable memory.
1143	 */
1144	reserve_crashkernel();
1145
1146	memblock_find_dma_reserve();
1147
1148	if (!early_xdbc_setup_hardware())
1149		early_xdbc_register_console();
1150
1151	x86_init.paging.pagetable_init();
1152
1153	kasan_init();
1154
1155	/*
1156	 * Sync back kernel address range.
1157	 *
1158	 * FIXME: Can the later sync in setup_cpu_entry_areas() replace
1159	 * this call?
1160	 */
1161	sync_initial_page_table();
1162
1163	tboot_probe();
1164
1165	map_vsyscall();
1166
1167	generic_apic_probe();
1168
1169	early_quirks();
1170
 
 
1171	/*
1172	 * Read APIC and some other early information from ACPI tables.
 
1173	 */
1174	acpi_boot_init();
1175	x86_dtb_init();
1176
1177	/*
1178	 * get boot-time SMP configuration:
1179	 */
1180	get_smp_config();
1181
1182	/*
1183	 * Systems w/o ACPI and mptables might not have it mapped the local
1184	 * APIC yet, but prefill_possible_map() might need to access it.
1185	 */
1186	init_apic_mappings();
1187
1188	prefill_possible_map();
1189
1190	init_cpu_to_node();
1191	init_gi_nodes();
1192
1193	io_apic_init_mappings();
1194
1195	x86_init.hyper.guest_late_init();
1196
1197	e820__reserve_resources();
1198	e820__register_nosave_regions(max_pfn);
1199
1200	x86_init.resources.reserve_resources();
1201
1202	e820__setup_pci_gap();
1203
1204#ifdef CONFIG_VT
1205#if defined(CONFIG_VGA_CONSOLE)
1206	if (!efi_enabled(EFI_BOOT) || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
1207		conswitchp = &vga_con;
1208#endif
1209#endif
1210	x86_init.oem.banner();
1211
1212	x86_init.timers.wallclock_init();
1213
1214	/*
1215	 * This needs to run before setup_local_APIC() which soft-disables the
1216	 * local APIC temporarily and that masks the thermal LVT interrupt,
1217	 * leading to softlockups on machines which have configured SMI
1218	 * interrupt delivery.
1219	 */
1220	therm_lvt_init();
1221
1222	mcheck_init();
1223
1224	register_refined_jiffies(CLOCK_TICK_RATE);
1225
1226#ifdef CONFIG_EFI
1227	if (efi_enabled(EFI_BOOT))
1228		efi_apply_memmap_quirks();
1229#endif
1230
1231	unwind_init();
1232}
1233
1234#ifdef CONFIG_X86_32
1235
1236static struct resource video_ram_resource = {
1237	.name	= "Video RAM area",
1238	.start	= 0xa0000,
1239	.end	= 0xbffff,
1240	.flags	= IORESOURCE_BUSY | IORESOURCE_MEM
1241};
1242
1243void __init i386_reserve_resources(void)
1244{
1245	request_resource(&iomem_resource, &video_ram_resource);
1246	reserve_standard_io_resources();
1247}
1248
1249#endif /* CONFIG_X86_32 */
1250
1251static struct notifier_block kernel_offset_notifier = {
1252	.notifier_call = dump_kernel_offset
1253};
1254
1255static int __init register_kernel_offset_dumper(void)
1256{
1257	atomic_notifier_chain_register(&panic_notifier_list,
1258					&kernel_offset_notifier);
1259	return 0;
1260}
1261__initcall(register_kernel_offset_dumper);