1 // SPDX-License-Identifier: GPL-2.0-only 2 3 /* ----------------------------------------------------------------------- 4 * 5 * Copyright 2011 Intel Corporation; author Matt Fleming 6 * 7 * ----------------------------------------------------------------------- */ 8 9 #include <linux/efi.h> 10 #include <linux/pci.h> 11 12 #include <asm/efi.h> 13 #include <asm/e820/types.h> 14 #include <asm/setup.h> 15 #include <asm/desc.h> 16 #include <asm/boot.h> 17 18 #include "efistub.h" 19 20 /* Maximum physical address for 64-bit kernel with 4-level paging */ 21 #define MAXMEM_X86_64_4LEVEL (1ull << 46) 22 23 const efi_system_table_t *efi_system_table; 24 extern const bool efi_is64; 25 extern u32 image_offset; 26 27 __attribute_const__ bool efi_is_64bit(void) 28 { 29 if (IS_ENABLED(CONFIG_EFI_MIXED)) 30 return efi_is64; 31 return IS_ENABLED(CONFIG_X86_64); 32 } 33 34 static efi_status_t 35 preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom) 36 { 37 struct pci_setup_rom *rom = NULL; 38 efi_status_t status; 39 unsigned long size; 40 uint64_t romsize; 41 void *romimage; 42 43 /* 44 * Some firmware images contain EFI function pointers at the place where 45 * the romimage and romsize fields are supposed to be. Typically the EFI 46 * code is mapped at high addresses, translating to an unrealistically 47 * large romsize. The UEFI spec limits the size of option ROMs to 16 48 * MiB so we reject any ROMs over 16 MiB in size to catch this. 49 */ 50 romimage = efi_table_attr(pci, romimage); 51 romsize = efi_table_attr(pci, romsize); 52 if (!romimage || !romsize || romsize > SZ_16M) 53 return EFI_INVALID_PARAMETER; 54 55 size = romsize + sizeof(*rom); 56 57 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, 58 (void **)&rom); 59 if (status != EFI_SUCCESS) { 60 efi_printk("Failed to allocate memory for 'rom'\n"); 61 return status; 62 } 63 64 memset(rom, 0, sizeof(*rom)); 65 66 rom->data.type = SETUP_PCI; 67 rom->data.len = size - sizeof(struct setup_data); 68 rom->data.next = 0; 69 rom->pcilen = pci->romsize; 70 *__rom = rom; 71 72 status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16, 73 PCI_VENDOR_ID, 1, &rom->vendor); 74 75 if (status != EFI_SUCCESS) { 76 efi_printk("Failed to read rom->vendor\n"); 77 goto free_struct; 78 } 79 80 status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16, 81 PCI_DEVICE_ID, 1, &rom->devid); 82 83 if (status != EFI_SUCCESS) { 84 efi_printk("Failed to read rom->devid\n"); 85 goto free_struct; 86 } 87 88 status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus, 89 &rom->device, &rom->function); 90 91 if (status != EFI_SUCCESS) 92 goto free_struct; 93 94 memcpy(rom->romdata, romimage, romsize); 95 return status; 96 97 free_struct: 98 efi_bs_call(free_pool, rom); 99 return status; 100 } 101 102 /* 103 * There's no way to return an informative status from this function, 104 * because any analysis (and printing of error messages) needs to be 105 * done directly at the EFI function call-site. 106 * 107 * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we 108 * just didn't find any PCI devices, but there's no way to tell outside 109 * the context of the call. 110 */ 111 static void setup_efi_pci(struct boot_params *params) 112 { 113 efi_status_t status; 114 void **pci_handle = NULL; 115 efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID; 116 unsigned long size = 0; 117 struct setup_data *data; 118 efi_handle_t h; 119 int i; 120 121 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, 122 &pci_proto, NULL, &size, pci_handle); 123 124 if (status == EFI_BUFFER_TOO_SMALL) { 125 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, 126 (void **)&pci_handle); 127 128 if (status != EFI_SUCCESS) { 129 efi_printk("Failed to allocate memory for 'pci_handle'\n"); 130 return; 131 } 132 133 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, 134 &pci_proto, NULL, &size, pci_handle); 135 } 136 137 if (status != EFI_SUCCESS) 138 goto free_handle; 139 140 data = (struct setup_data *)(unsigned long)params->hdr.setup_data; 141 142 while (data && data->next) 143 data = (struct setup_data *)(unsigned long)data->next; 144 145 for_each_efi_handle(h, pci_handle, size, i) { 146 efi_pci_io_protocol_t *pci = NULL; 147 struct pci_setup_rom *rom; 148 149 status = efi_bs_call(handle_protocol, h, &pci_proto, 150 (void **)&pci); 151 if (status != EFI_SUCCESS || !pci) 152 continue; 153 154 status = preserve_pci_rom_image(pci, &rom); 155 if (status != EFI_SUCCESS) 156 continue; 157 158 if (data) 159 data->next = (unsigned long)rom; 160 else 161 params->hdr.setup_data = (unsigned long)rom; 162 163 data = (struct setup_data *)rom; 164 } 165 166 free_handle: 167 efi_bs_call(free_pool, pci_handle); 168 } 169 170 static void retrieve_apple_device_properties(struct boot_params *boot_params) 171 { 172 efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID; 173 struct setup_data *data, *new; 174 efi_status_t status; 175 u32 size = 0; 176 apple_properties_protocol_t *p; 177 178 status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p); 179 if (status != EFI_SUCCESS) 180 return; 181 182 if (efi_table_attr(p, version) != 0x10000) { 183 efi_printk("Unsupported properties proto version\n"); 184 return; 185 } 186 187 efi_call_proto(p, get_all, NULL, &size); 188 if (!size) 189 return; 190 191 do { 192 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, 193 size + sizeof(struct setup_data), 194 (void **)&new); 195 if (status != EFI_SUCCESS) { 196 efi_printk("Failed to allocate memory for 'properties'\n"); 197 return; 198 } 199 200 status = efi_call_proto(p, get_all, new->data, &size); 201 202 if (status == EFI_BUFFER_TOO_SMALL) 203 efi_bs_call(free_pool, new); 204 } while (status == EFI_BUFFER_TOO_SMALL); 205 206 new->type = SETUP_APPLE_PROPERTIES; 207 new->len = size; 208 new->next = 0; 209 210 data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data; 211 if (!data) { 212 boot_params->hdr.setup_data = (unsigned long)new; 213 } else { 214 while (data->next) 215 data = (struct setup_data *)(unsigned long)data->next; 216 data->next = (unsigned long)new; 217 } 218 } 219 220 static const efi_char16_t apple[] = L"Apple"; 221 222 static void setup_quirks(struct boot_params *boot_params) 223 { 224 efi_char16_t *fw_vendor = (efi_char16_t *)(unsigned long) 225 efi_table_attr(efi_system_table, fw_vendor); 226 227 if (!memcmp(fw_vendor, apple, sizeof(apple))) { 228 if (IS_ENABLED(CONFIG_APPLE_PROPERTIES)) 229 retrieve_apple_device_properties(boot_params); 230 } 231 } 232 233 /* 234 * See if we have Universal Graphics Adapter (UGA) protocol 235 */ 236 static efi_status_t 237 setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size) 238 { 239 efi_status_t status; 240 u32 width, height; 241 void **uga_handle = NULL; 242 efi_uga_draw_protocol_t *uga = NULL, *first_uga; 243 efi_handle_t handle; 244 int i; 245 246 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, 247 (void **)&uga_handle); 248 if (status != EFI_SUCCESS) 249 return status; 250 251 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, 252 uga_proto, NULL, &size, uga_handle); 253 if (status != EFI_SUCCESS) 254 goto free_handle; 255 256 height = 0; 257 width = 0; 258 259 first_uga = NULL; 260 for_each_efi_handle(handle, uga_handle, size, i) { 261 efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID; 262 u32 w, h, depth, refresh; 263 void *pciio; 264 265 status = efi_bs_call(handle_protocol, handle, uga_proto, 266 (void **)&uga); 267 if (status != EFI_SUCCESS) 268 continue; 269 270 pciio = NULL; 271 efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio); 272 273 status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh); 274 if (status == EFI_SUCCESS && (!first_uga || pciio)) { 275 width = w; 276 height = h; 277 278 /* 279 * Once we've found a UGA supporting PCIIO, 280 * don't bother looking any further. 281 */ 282 if (pciio) 283 break; 284 285 first_uga = uga; 286 } 287 } 288 289 if (!width && !height) 290 goto free_handle; 291 292 /* EFI framebuffer */ 293 si->orig_video_isVGA = VIDEO_TYPE_EFI; 294 295 si->lfb_depth = 32; 296 si->lfb_width = width; 297 si->lfb_height = height; 298 299 si->red_size = 8; 300 si->red_pos = 16; 301 si->green_size = 8; 302 si->green_pos = 8; 303 si->blue_size = 8; 304 si->blue_pos = 0; 305 si->rsvd_size = 8; 306 si->rsvd_pos = 24; 307 308 free_handle: 309 efi_bs_call(free_pool, uga_handle); 310 311 return status; 312 } 313 314 static void setup_graphics(struct boot_params *boot_params) 315 { 316 efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID; 317 struct screen_info *si; 318 efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID; 319 efi_status_t status; 320 unsigned long size; 321 void **gop_handle = NULL; 322 void **uga_handle = NULL; 323 324 si = &boot_params->screen_info; 325 memset(si, 0, sizeof(*si)); 326 327 size = 0; 328 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, 329 &graphics_proto, NULL, &size, gop_handle); 330 if (status == EFI_BUFFER_TOO_SMALL) 331 status = efi_setup_gop(si, &graphics_proto, size); 332 333 if (status != EFI_SUCCESS) { 334 size = 0; 335 status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, 336 &uga_proto, NULL, &size, uga_handle); 337 if (status == EFI_BUFFER_TOO_SMALL) 338 setup_uga(si, &uga_proto, size); 339 } 340 } 341 342 343 static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status) 344 { 345 efi_bs_call(exit, handle, status, 0, NULL); 346 for(;;) 347 asm("hlt"); 348 } 349 350 void startup_32(struct boot_params *boot_params); 351 352 void __noreturn efi_stub_entry(efi_handle_t handle, 353 efi_system_table_t *sys_table_arg, 354 struct boot_params *boot_params); 355 356 /* 357 * Because the x86 boot code expects to be passed a boot_params we 358 * need to create one ourselves (usually the bootloader would create 359 * one for us). 360 */ 361 efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, 362 efi_system_table_t *sys_table_arg) 363 { 364 struct boot_params *boot_params; 365 struct setup_header *hdr; 366 efi_loaded_image_t *image; 367 void *image_base; 368 efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID; 369 int options_size = 0; 370 efi_status_t status; 371 char *cmdline_ptr; 372 unsigned long ramdisk_addr; 373 unsigned long ramdisk_size; 374 375 efi_system_table = sys_table_arg; 376 377 /* Check if we were booted by the EFI firmware */ 378 if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) 379 efi_exit(handle, EFI_INVALID_PARAMETER); 380 381 status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image); 382 if (status != EFI_SUCCESS) { 383 efi_printk("Failed to get handle for LOADED_IMAGE_PROTOCOL\n"); 384 efi_exit(handle, status); 385 } 386 387 image_base = efi_table_attr(image, image_base); 388 image_offset = (void *)startup_32 - image_base; 389 390 status = efi_allocate_pages(0x4000, (unsigned long *)&boot_params, ULONG_MAX); 391 if (status != EFI_SUCCESS) { 392 efi_printk("Failed to allocate lowmem for boot params\n"); 393 efi_exit(handle, status); 394 } 395 396 memset(boot_params, 0x0, 0x4000); 397 398 hdr = &boot_params->hdr; 399 400 /* Copy the second sector to boot_params */ 401 memcpy(&hdr->jump, image_base + 512, 512); 402 403 /* 404 * Fill out some of the header fields ourselves because the 405 * EFI firmware loader doesn't load the first sector. 406 */ 407 hdr->root_flags = 1; 408 hdr->vid_mode = 0xffff; 409 hdr->boot_flag = 0xAA55; 410 411 hdr->type_of_loader = 0x21; 412 413 /* Convert unicode cmdline to ascii */ 414 cmdline_ptr = efi_convert_cmdline(image, &options_size, ULONG_MAX); 415 if (!cmdline_ptr) 416 goto fail; 417 418 hdr->cmd_line_ptr = (unsigned long)cmdline_ptr; 419 /* Fill in upper bits of command line address, NOP on 32 bit */ 420 boot_params->ext_cmd_line_ptr = (u64)(unsigned long)cmdline_ptr >> 32; 421 422 hdr->ramdisk_image = 0; 423 hdr->ramdisk_size = 0; 424 425 if (efi_is_native()) { 426 status = efi_parse_options(cmdline_ptr); 427 if (status != EFI_SUCCESS) 428 goto fail2; 429 430 if (!efi_noinitrd) { 431 status = efi_load_initrd(image, &ramdisk_addr, 432 &ramdisk_size, 433 hdr->initrd_addr_max, 434 ULONG_MAX); 435 if (status != EFI_SUCCESS) 436 goto fail2; 437 hdr->ramdisk_image = ramdisk_addr & 0xffffffff; 438 hdr->ramdisk_size = ramdisk_size & 0xffffffff; 439 boot_params->ext_ramdisk_image = (u64)ramdisk_addr >> 32; 440 boot_params->ext_ramdisk_size = (u64)ramdisk_size >> 32; 441 } 442 } 443 444 efi_stub_entry(handle, sys_table_arg, boot_params); 445 /* not reached */ 446 447 fail2: 448 efi_free(options_size, (unsigned long)cmdline_ptr); 449 fail: 450 efi_free(0x4000, (unsigned long)boot_params); 451 452 efi_exit(handle, status); 453 } 454 455 static void add_e820ext(struct boot_params *params, 456 struct setup_data *e820ext, u32 nr_entries) 457 { 458 struct setup_data *data; 459 460 e820ext->type = SETUP_E820_EXT; 461 e820ext->len = nr_entries * sizeof(struct boot_e820_entry); 462 e820ext->next = 0; 463 464 data = (struct setup_data *)(unsigned long)params->hdr.setup_data; 465 466 while (data && data->next) 467 data = (struct setup_data *)(unsigned long)data->next; 468 469 if (data) 470 data->next = (unsigned long)e820ext; 471 else 472 params->hdr.setup_data = (unsigned long)e820ext; 473 } 474 475 static efi_status_t 476 setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size) 477 { 478 struct boot_e820_entry *entry = params->e820_table; 479 struct efi_info *efi = ¶ms->efi_info; 480 struct boot_e820_entry *prev = NULL; 481 u32 nr_entries; 482 u32 nr_desc; 483 int i; 484 485 nr_entries = 0; 486 nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size; 487 488 for (i = 0; i < nr_desc; i++) { 489 efi_memory_desc_t *d; 490 unsigned int e820_type = 0; 491 unsigned long m = efi->efi_memmap; 492 493 #ifdef CONFIG_X86_64 494 m |= (u64)efi->efi_memmap_hi << 32; 495 #endif 496 497 d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i); 498 switch (d->type) { 499 case EFI_RESERVED_TYPE: 500 case EFI_RUNTIME_SERVICES_CODE: 501 case EFI_RUNTIME_SERVICES_DATA: 502 case EFI_MEMORY_MAPPED_IO: 503 case EFI_MEMORY_MAPPED_IO_PORT_SPACE: 504 case EFI_PAL_CODE: 505 e820_type = E820_TYPE_RESERVED; 506 break; 507 508 case EFI_UNUSABLE_MEMORY: 509 e820_type = E820_TYPE_UNUSABLE; 510 break; 511 512 case EFI_ACPI_RECLAIM_MEMORY: 513 e820_type = E820_TYPE_ACPI; 514 break; 515 516 case EFI_LOADER_CODE: 517 case EFI_LOADER_DATA: 518 case EFI_BOOT_SERVICES_CODE: 519 case EFI_BOOT_SERVICES_DATA: 520 case EFI_CONVENTIONAL_MEMORY: 521 if (efi_soft_reserve_enabled() && 522 (d->attribute & EFI_MEMORY_SP)) 523 e820_type = E820_TYPE_SOFT_RESERVED; 524 else 525 e820_type = E820_TYPE_RAM; 526 break; 527 528 case EFI_ACPI_MEMORY_NVS: 529 e820_type = E820_TYPE_NVS; 530 break; 531 532 case EFI_PERSISTENT_MEMORY: 533 e820_type = E820_TYPE_PMEM; 534 break; 535 536 default: 537 continue; 538 } 539 540 /* Merge adjacent mappings */ 541 if (prev && prev->type == e820_type && 542 (prev->addr + prev->size) == d->phys_addr) { 543 prev->size += d->num_pages << 12; 544 continue; 545 } 546 547 if (nr_entries == ARRAY_SIZE(params->e820_table)) { 548 u32 need = (nr_desc - i) * sizeof(struct e820_entry) + 549 sizeof(struct setup_data); 550 551 if (!e820ext || e820ext_size < need) 552 return EFI_BUFFER_TOO_SMALL; 553 554 /* boot_params map full, switch to e820 extended */ 555 entry = (struct boot_e820_entry *)e820ext->data; 556 } 557 558 entry->addr = d->phys_addr; 559 entry->size = d->num_pages << PAGE_SHIFT; 560 entry->type = e820_type; 561 prev = entry++; 562 nr_entries++; 563 } 564 565 if (nr_entries > ARRAY_SIZE(params->e820_table)) { 566 u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table); 567 568 add_e820ext(params, e820ext, nr_e820ext); 569 nr_entries -= nr_e820ext; 570 } 571 572 params->e820_entries = (u8)nr_entries; 573 574 return EFI_SUCCESS; 575 } 576 577 static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext, 578 u32 *e820ext_size) 579 { 580 efi_status_t status; 581 unsigned long size; 582 583 size = sizeof(struct setup_data) + 584 sizeof(struct e820_entry) * nr_desc; 585 586 if (*e820ext) { 587 efi_bs_call(free_pool, *e820ext); 588 *e820ext = NULL; 589 *e820ext_size = 0; 590 } 591 592 status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, 593 (void **)e820ext); 594 if (status == EFI_SUCCESS) 595 *e820ext_size = size; 596 597 return status; 598 } 599 600 static efi_status_t allocate_e820(struct boot_params *params, 601 struct setup_data **e820ext, 602 u32 *e820ext_size) 603 { 604 unsigned long map_size, desc_size, buff_size; 605 struct efi_boot_memmap boot_map; 606 efi_memory_desc_t *map; 607 efi_status_t status; 608 __u32 nr_desc; 609 610 boot_map.map = ↦ 611 boot_map.map_size = &map_size; 612 boot_map.desc_size = &desc_size; 613 boot_map.desc_ver = NULL; 614 boot_map.key_ptr = NULL; 615 boot_map.buff_size = &buff_size; 616 617 status = efi_get_memory_map(&boot_map); 618 if (status != EFI_SUCCESS) 619 return status; 620 621 nr_desc = buff_size / desc_size; 622 623 if (nr_desc > ARRAY_SIZE(params->e820_table)) { 624 u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table); 625 626 status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size); 627 if (status != EFI_SUCCESS) 628 return status; 629 } 630 631 return EFI_SUCCESS; 632 } 633 634 struct exit_boot_struct { 635 struct boot_params *boot_params; 636 struct efi_info *efi; 637 }; 638 639 static efi_status_t exit_boot_func(struct efi_boot_memmap *map, 640 void *priv) 641 { 642 const char *signature; 643 struct exit_boot_struct *p = priv; 644 645 signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE 646 : EFI32_LOADER_SIGNATURE; 647 memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32)); 648 649 p->efi->efi_systab = (unsigned long)efi_system_table; 650 p->efi->efi_memdesc_size = *map->desc_size; 651 p->efi->efi_memdesc_version = *map->desc_ver; 652 p->efi->efi_memmap = (unsigned long)*map->map; 653 p->efi->efi_memmap_size = *map->map_size; 654 655 #ifdef CONFIG_X86_64 656 p->efi->efi_systab_hi = (unsigned long)efi_system_table >> 32; 657 p->efi->efi_memmap_hi = (unsigned long)*map->map >> 32; 658 #endif 659 660 return EFI_SUCCESS; 661 } 662 663 static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) 664 { 665 unsigned long map_sz, key, desc_size, buff_size; 666 efi_memory_desc_t *mem_map; 667 struct setup_data *e820ext = NULL; 668 __u32 e820ext_size = 0; 669 efi_status_t status; 670 __u32 desc_version; 671 struct efi_boot_memmap map; 672 struct exit_boot_struct priv; 673 674 map.map = &mem_map; 675 map.map_size = &map_sz; 676 map.desc_size = &desc_size; 677 map.desc_ver = &desc_version; 678 map.key_ptr = &key; 679 map.buff_size = &buff_size; 680 priv.boot_params = boot_params; 681 priv.efi = &boot_params->efi_info; 682 683 status = allocate_e820(boot_params, &e820ext, &e820ext_size); 684 if (status != EFI_SUCCESS) 685 return status; 686 687 /* Might as well exit boot services now */ 688 status = efi_exit_boot_services(handle, &map, &priv, exit_boot_func); 689 if (status != EFI_SUCCESS) 690 return status; 691 692 /* Historic? */ 693 boot_params->alt_mem_k = 32 * 1024; 694 695 status = setup_e820(boot_params, e820ext, e820ext_size); 696 if (status != EFI_SUCCESS) 697 return status; 698 699 return EFI_SUCCESS; 700 } 701 702 /* 703 * On success, we return the address of startup_32, which has potentially been 704 * relocated by efi_relocate_kernel. 705 * On failure, we exit to the firmware via efi_exit instead of returning. 706 */ 707 unsigned long efi_main(efi_handle_t handle, 708 efi_system_table_t *sys_table_arg, 709 struct boot_params *boot_params) 710 { 711 unsigned long bzimage_addr = (unsigned long)startup_32; 712 unsigned long buffer_start, buffer_end; 713 struct setup_header *hdr = &boot_params->hdr; 714 efi_status_t status; 715 unsigned long cmdline_paddr; 716 717 efi_system_table = sys_table_arg; 718 719 /* Check if we were booted by the EFI firmware */ 720 if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) 721 efi_exit(handle, EFI_INVALID_PARAMETER); 722 723 /* 724 * If the kernel isn't already loaded at a suitable address, 725 * relocate it. 726 * 727 * It must be loaded above LOAD_PHYSICAL_ADDR. 728 * 729 * The maximum address for 64-bit is 1 << 46 for 4-level paging. This 730 * is defined as the macro MAXMEM, but unfortunately that is not a 731 * compile-time constant if 5-level paging is configured, so we instead 732 * define our own macro for use here. 733 * 734 * For 32-bit, the maximum address is complicated to figure out, for 735 * now use KERNEL_IMAGE_SIZE, which will be 512MiB, the same as what 736 * KASLR uses. 737 * 738 * Also relocate it if image_offset is zero, i.e. the kernel wasn't 739 * loaded by LoadImage, but rather by a bootloader that called the 740 * handover entry. The reason we must always relocate in this case is 741 * to handle the case of systemd-boot booting a unified kernel image, 742 * which is a PE executable that contains the bzImage and an initrd as 743 * COFF sections. The initrd section is placed after the bzImage 744 * without ensuring that there are at least init_size bytes available 745 * for the bzImage, and thus the compressed kernel's startup code may 746 * overwrite the initrd unless it is moved out of the way. 747 */ 748 749 buffer_start = ALIGN(bzimage_addr - image_offset, 750 hdr->kernel_alignment); 751 buffer_end = buffer_start + hdr->init_size; 752 753 if ((buffer_start < LOAD_PHYSICAL_ADDR) || 754 (IS_ENABLED(CONFIG_X86_32) && buffer_end > KERNEL_IMAGE_SIZE) || 755 (IS_ENABLED(CONFIG_X86_64) && buffer_end > MAXMEM_X86_64_4LEVEL) || 756 (image_offset == 0)) { 757 status = efi_relocate_kernel(&bzimage_addr, 758 hdr->init_size, hdr->init_size, 759 hdr->pref_address, 760 hdr->kernel_alignment, 761 LOAD_PHYSICAL_ADDR); 762 if (status != EFI_SUCCESS) { 763 efi_printk("efi_relocate_kernel() failed!\n"); 764 goto fail; 765 } 766 /* 767 * Now that we've copied the kernel elsewhere, we no longer 768 * have a set up block before startup_32(), so reset image_offset 769 * to zero in case it was set earlier. 770 */ 771 image_offset = 0; 772 } 773 774 /* 775 * efi_pe_entry() may have been called before efi_main(), in which 776 * case this is the second time we parse the cmdline. This is ok, 777 * parsing the cmdline multiple times does not have side-effects. 778 */ 779 cmdline_paddr = ((u64)hdr->cmd_line_ptr | 780 ((u64)boot_params->ext_cmd_line_ptr << 32)); 781 efi_parse_options((char *)cmdline_paddr); 782 783 /* 784 * At this point, an initrd may already have been loaded, either by 785 * the bootloader and passed via bootparams, or loaded from a initrd= 786 * command line option by efi_pe_entry() above. In either case, we 787 * permit an initrd loaded from the LINUX_EFI_INITRD_MEDIA_GUID device 788 * path to supersede it. 789 */ 790 if (!efi_noinitrd) { 791 unsigned long addr, size; 792 793 status = efi_load_initrd_dev_path(&addr, &size, ULONG_MAX); 794 if (status == EFI_SUCCESS) { 795 hdr->ramdisk_image = (u32)addr; 796 hdr->ramdisk_size = (u32)size; 797 boot_params->ext_ramdisk_image = (u64)addr >> 32; 798 boot_params->ext_ramdisk_size = (u64)size >> 32; 799 } else if (status != EFI_NOT_FOUND) { 800 efi_printk("efi_load_initrd_dev_path() failed!\n"); 801 goto fail; 802 } 803 } 804 805 /* 806 * If the boot loader gave us a value for secure_boot then we use that, 807 * otherwise we ask the BIOS. 808 */ 809 if (boot_params->secure_boot == efi_secureboot_mode_unset) 810 boot_params->secure_boot = efi_get_secureboot(); 811 812 /* Ask the firmware to clear memory on unclean shutdown */ 813 efi_enable_reset_attack_mitigation(); 814 815 efi_random_get_seed(); 816 817 efi_retrieve_tpm2_eventlog(); 818 819 setup_graphics(boot_params); 820 821 setup_efi_pci(boot_params); 822 823 setup_quirks(boot_params); 824 825 status = exit_boot(boot_params, handle); 826 if (status != EFI_SUCCESS) { 827 efi_printk("exit_boot() failed!\n"); 828 goto fail; 829 } 830 831 return bzimage_addr; 832 fail: 833 efi_printk("efi_main() failed!\n"); 834 835 efi_exit(handle, status); 836 } 837