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