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
#include <linux/stddef.h>
12

13
#include <asm/efi.h>
14
#include <asm/e820/types.h>
15
#include <asm/setup.h>
16
#include <asm/desc.h>
17
#include <asm/boot.h>
18
#include <asm/kaslr.h>
19
#include <asm/sev.h>
20

21
#include "efistub.h"
22
#include "x86-stub.h"
23

24
extern char _bss[], _ebss[];
25

26
const efi_system_table_t *efi_system_table;
27
const efi_dxe_services_table_t *efi_dxe_table;
28
static efi_loaded_image_t *image = NULL;
29
static efi_memory_attribute_protocol_t *memattr;
30

31
typedef union sev_memory_acceptance_protocol sev_memory_acceptance_protocol_t;
32
union sev_memory_acceptance_protocol {
33
	struct {
34
		efi_status_t (__efiapi * allow_unaccepted_memory)(
35
			sev_memory_acceptance_protocol_t *);
36
	};
37
	struct {
38
		u32 allow_unaccepted_memory;
39
	} mixed_mode;
40
};
41

42
static efi_status_t
43
preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)
44
{
45
	struct pci_setup_rom *rom __free(efi_pool) = NULL;
46
	efi_status_t status;
47
	unsigned long size;
48
	uint64_t romsize;
49
	void *romimage;
50

51
	/*
52
	 * Some firmware images contain EFI function pointers at the place where
53
	 * the romimage and romsize fields are supposed to be. Typically the EFI
54
	 * code is mapped at high addresses, translating to an unrealistically
55
	 * large romsize. The UEFI spec limits the size of option ROMs to 16
56
	 * MiB so we reject any ROMs over 16 MiB in size to catch this.
57
	 */
58
	romimage = efi_table_attr(pci, romimage);
59
	romsize = efi_table_attr(pci, romsize);
60
	if (!romimage || !romsize || romsize > SZ_16M)
61
		return EFI_INVALID_PARAMETER;
62

63
	size = romsize + sizeof(*rom);
64

65
	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
66
			     (void **)&rom);
67
	if (status != EFI_SUCCESS) {
68
		efi_err("Failed to allocate memory for 'rom'\n");
69
		return status;
70
	}
71

72
	memset(rom, 0, sizeof(*rom));
73

74
	rom->data.type	= SETUP_PCI;
75
	rom->data.len	= size - sizeof(struct setup_data);
76
	rom->data.next	= 0;
77
	rom->pcilen	= romsize;
78

79
	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
80
				PCI_VENDOR_ID, 1, &rom->vendor);
81

82
	if (status != EFI_SUCCESS) {
83
		efi_err("Failed to read rom->vendor\n");
84
		return status;
85
	}
86

87
	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,
88
				PCI_DEVICE_ID, 1, &rom->devid);
89

90
	if (status != EFI_SUCCESS) {
91
		efi_err("Failed to read rom->devid\n");
92
		return status;
93
	}
94

95
	status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus,
96
				&rom->device, &rom->function);
97

98
	if (status != EFI_SUCCESS)
99
		return status;
100

101
	memcpy(rom->romdata, romimage, romsize);
102
	*__rom = no_free_ptr(rom);
103
	return EFI_SUCCESS;
104
}
105

106
/*
107
 * There's no way to return an informative status from this function,
108
 * because any analysis (and printing of error messages) needs to be
109
 * done directly at the EFI function call-site.
110
 *
111
 * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we
112
 * just didn't find any PCI devices, but there's no way to tell outside
113
 * the context of the call.
114
 */
115
static void setup_efi_pci(struct boot_params *params)
116
{
117
	efi_status_t status;
118
	efi_handle_t *pci_handle __free(efi_pool) = NULL;
119
	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;
120
	struct setup_data *data;
121
	unsigned long num;
122
	efi_handle_t h;
123

124
	status = efi_bs_call(locate_handle_buffer, EFI_LOCATE_BY_PROTOCOL,
125
			     &pci_proto, NULL, &num, &pci_handle);
126
	if (status != EFI_SUCCESS)
127
		return;
128

129
	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
130

131
	while (data && data->next)
132
		data = (struct setup_data *)(unsigned long)data->next;
133

134
	for_each_efi_handle(h, pci_handle, num) {
135
		efi_pci_io_protocol_t *pci = NULL;
136
		struct pci_setup_rom *rom;
137

138
		status = efi_bs_call(handle_protocol, h, &pci_proto,
139
				     (void **)&pci);
140
		if (status != EFI_SUCCESS || !pci)
141
			continue;
142

143
		status = preserve_pci_rom_image(pci, &rom);
144
		if (status != EFI_SUCCESS)
145
			continue;
146

147
		if (data)
148
			data->next = (unsigned long)rom;
149
		else
150
			params->hdr.setup_data = (unsigned long)rom;
151

152
		data = (struct setup_data *)rom;
153
	}
154
}
155

156
static void retrieve_apple_device_properties(struct boot_params *boot_params)
157
{
158
	efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;
159
	struct setup_data *data, *new;
160
	efi_status_t status;
161
	u32 size = 0;
162
	apple_properties_protocol_t *p;
163

164
	status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p);
165
	if (status != EFI_SUCCESS)
166
		return;
167

168
	if (efi_table_attr(p, version) != 0x10000) {
169
		efi_err("Unsupported properties proto version\n");
170
		return;
171
	}
172

173
	efi_call_proto(p, get_all, NULL, &size);
174
	if (!size)
175
		return;
176

177
	do {
178
		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,
179
				     size + sizeof(struct setup_data),
180
				     (void **)&new);
181
		if (status != EFI_SUCCESS) {
182
			efi_err("Failed to allocate memory for 'properties'\n");
183
			return;
184
		}
185

186
		status = efi_call_proto(p, get_all, new->data, &size);
187

188
		if (status == EFI_BUFFER_TOO_SMALL)
189
			efi_bs_call(free_pool, new);
190
	} while (status == EFI_BUFFER_TOO_SMALL);
191

192
	new->type = SETUP_APPLE_PROPERTIES;
193
	new->len  = size;
194
	new->next = 0;
195

196
	data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;
197
	if (!data) {
198
		boot_params->hdr.setup_data = (unsigned long)new;
199
	} else {
200
		while (data->next)
201
			data = (struct setup_data *)(unsigned long)data->next;
202
		data->next = (unsigned long)new;
203
	}
204
}
205

206
static bool apple_match_product_name(void)
207
{
208
	static const char type1_product_matches[][15] = {
209
		"MacBookPro11,3",
210
		"MacBookPro11,5",
211
		"MacBookPro13,3",
212
		"MacBookPro14,3",
213
		"MacBookPro15,1",
214
		"MacBookPro15,3",
215
		"MacBookPro16,1",
216
		"MacBookPro16,4",
217
	};
218
	const struct efi_smbios_type1_record *record;
219
	const u8 *product;
220

221
	record = (struct efi_smbios_type1_record *)efi_get_smbios_record(1);
222
	if (!record)
223
		return false;
224

225
	product = efi_get_smbios_string(record, product_name);
226
	if (!product)
227
		return false;
228

229
	for (int i = 0; i < ARRAY_SIZE(type1_product_matches); i++) {
230
		if (!strcmp(product, type1_product_matches[i]))
231
			return true;
232
	}
233

234
	return false;
235
}
236

237
static void apple_set_os(void)
238
{
239
	struct {
240
		unsigned long version;
241
		efi_status_t (__efiapi *set_os_version)(const char *);
242
		efi_status_t (__efiapi *set_os_vendor)(const char *);
243
	} *set_os;
244
	efi_status_t status;
245

246
	if (!efi_is_64bit() || !apple_match_product_name())
247
		return;
248

249
	status = efi_bs_call(locate_protocol, &APPLE_SET_OS_PROTOCOL_GUID, NULL,
250
			     (void **)&set_os);
251
	if (status != EFI_SUCCESS)
252
		return;
253

254
	if (set_os->version >= 2) {
255
		status = set_os->set_os_vendor("Apple Inc.");
256
		if (status != EFI_SUCCESS)
257
			efi_err("Failed to set OS vendor via apple_set_os\n");
258
	}
259

260
	if (set_os->version > 0) {
261
		/* The version being set doesn't seem to matter */
262
		status = set_os->set_os_version("Mac OS X 10.9");
263
		if (status != EFI_SUCCESS)
264
			efi_err("Failed to set OS version via apple_set_os\n");
265
	}
266
}
267

268
efi_status_t efi_adjust_memory_range_protection(unsigned long start,
269
						unsigned long size)
270
{
271
	efi_status_t status;
272
	efi_gcd_memory_space_desc_t desc;
273
	unsigned long end, next;
274
	unsigned long rounded_start, rounded_end;
275
	unsigned long unprotect_start, unprotect_size;
276

277
	rounded_start = rounddown(start, EFI_PAGE_SIZE);
278
	rounded_end = roundup(start + size, EFI_PAGE_SIZE);
279

280
	if (memattr != NULL) {
281
		status = efi_call_proto(memattr, set_memory_attributes,
282
					rounded_start,
283
					rounded_end - rounded_start,
284
					EFI_MEMORY_RO);
285
		if (status != EFI_SUCCESS) {
286
			efi_warn("Failed to set EFI_MEMORY_RO attribute\n");
287
			return status;
288
		}
289

290
		status = efi_call_proto(memattr, clear_memory_attributes,
291
					rounded_start,
292
					rounded_end - rounded_start,
293
					EFI_MEMORY_XP);
294
		if (status != EFI_SUCCESS)
295
			efi_warn("Failed to clear EFI_MEMORY_XP attribute\n");
296
		return status;
297
	}
298

299
	if (efi_dxe_table == NULL)
300
		return EFI_SUCCESS;
301

302
	/*
303
	 * Don't modify memory region attributes, if they are
304
	 * already suitable, to lower the possibility to
305
	 * encounter firmware bugs.
306
	 */
307

308
	for (end = start + size; start < end; start = next) {
309

310
		status = efi_dxe_call(get_memory_space_descriptor, start, &desc);
311

312
		if (status != EFI_SUCCESS)
313
			break;
314

315
		next = desc.base_address + desc.length;
316

317
		/*
318
		 * Only system memory and more reliable memory are suitable for
319
		 * trampoline/kernel image placement. So only those memory types
320
		 * may need to have attributes modified.
321
		 */
322

323
		if ((desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory &&
324
		     desc.gcd_memory_type != EfiGcdMemoryTypeMoreReliable) ||
325
		    (desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0)
326
			continue;
327

328
		unprotect_start = max(rounded_start, (unsigned long)desc.base_address);
329
		unprotect_size = min(rounded_end, next) - unprotect_start;
330

331
		status = efi_dxe_call(set_memory_space_attributes,
332
				      unprotect_start, unprotect_size,
333
				      EFI_MEMORY_WB);
334

335
		if (status != EFI_SUCCESS) {
336
			efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n",
337
				 unprotect_start,
338
				 unprotect_start + unprotect_size,
339
				 status);
340
			break;
341
		}
342
	}
343
	return EFI_SUCCESS;
344
}
345

346
static void setup_unaccepted_memory(void)
347
{
348
	efi_guid_t mem_acceptance_proto = OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL_GUID;
349
	sev_memory_acceptance_protocol_t *proto;
350
	efi_status_t status;
351

352
	if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))
353
		return;
354

355
	/*
356
	 * Enable unaccepted memory before calling exit boot services in order
357
	 * for the UEFI to not accept all memory on EBS.
358
	 */
359
	status = efi_bs_call(locate_protocol, &mem_acceptance_proto, NULL,
360
			     (void **)&proto);
361
	if (status != EFI_SUCCESS)
362
		return;
363

364
	status = efi_call_proto(proto, allow_unaccepted_memory);
365
	if (status != EFI_SUCCESS)
366
		efi_err("Memory acceptance protocol failed\n");
367
}
368

369
static efi_char16_t *efistub_fw_vendor(void)
370
{
371
	unsigned long vendor = efi_table_attr(efi_system_table, fw_vendor);
372

373
	return (efi_char16_t *)vendor;
374
}
375

376
static const efi_char16_t apple[] = L"Apple";
377

378
static void setup_quirks(struct boot_params *boot_params)
379
{
380
	if (!memcmp(efistub_fw_vendor(), apple, sizeof(apple))) {
381
		if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))
382
			retrieve_apple_device_properties(boot_params);
383

384
		apple_set_os();
385
	}
386
}
387

388
static void setup_graphics(struct boot_params *boot_params)
389
{
390
	struct screen_info *si = memset(&boot_params->screen_info, 0, sizeof(*si));
391

392
	efi_setup_gop(si);
393
}
394

395
static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)
396
{
397
	efi_bs_call(exit, handle, status, 0, NULL);
398
	for(;;)
399
		asm("hlt");
400
}
401

402
/*
403
 * Because the x86 boot code expects to be passed a boot_params we
404
 * need to create one ourselves (usually the bootloader would create
405
 * one for us).
406
 */
407
static efi_status_t efi_allocate_bootparams(efi_handle_t handle,
408
					    struct boot_params **bp)
409
{
410
	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;
411
	struct boot_params *boot_params;
412
	struct setup_header *hdr;
413
	efi_status_t status;
414
	unsigned long alloc;
415
	char *cmdline_ptr;
416

417
	status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image);
418
	if (status != EFI_SUCCESS) {
419
		efi_err("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");
420
		return status;
421
	}
422

423
	status = efi_allocate_pages(PARAM_SIZE, &alloc, ULONG_MAX);
424
	if (status != EFI_SUCCESS)
425
		return status;
426

427
	boot_params = memset((void *)alloc, 0x0, PARAM_SIZE);
428
	hdr	    = &boot_params->hdr;
429

430
	/* Assign the setup_header fields that the kernel actually cares about */
431
	hdr->root_flags	= 1;
432
	hdr->vid_mode	= 0xffff;
433

434
	hdr->type_of_loader = 0x21;
435
	hdr->initrd_addr_max = INT_MAX;
436

437
	/* Convert unicode cmdline to ascii */
438
	cmdline_ptr = efi_convert_cmdline(image);
439
	if (!cmdline_ptr) {
440
		efi_free(PARAM_SIZE, alloc);
441
		return EFI_OUT_OF_RESOURCES;
442
	}
443

444
	efi_set_u64_split((unsigned long)cmdline_ptr, &hdr->cmd_line_ptr,
445
			  &boot_params->ext_cmd_line_ptr);
446

447
	*bp = boot_params;
448
	return EFI_SUCCESS;
449
}
450

451
static void add_e820ext(struct boot_params *params,
452
			struct setup_data *e820ext, u32 nr_entries)
453
{
454
	struct setup_data *data;
455

456
	e820ext->type = SETUP_E820_EXT;
457
	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);
458
	e820ext->next = 0;
459

460
	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;
461

462
	while (data && data->next)
463
		data = (struct setup_data *)(unsigned long)data->next;
464

465
	if (data)
466
		data->next = (unsigned long)e820ext;
467
	else
468
		params->hdr.setup_data = (unsigned long)e820ext;
469
}
470

471
static efi_status_t
472
setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)
473
{
474
	struct boot_e820_entry *entry = params->e820_table;
475
	struct efi_info *efi = &params->efi_info;
476
	struct boot_e820_entry *prev = NULL;
477
	u32 nr_entries;
478
	u32 nr_desc;
479
	int i;
480

481
	nr_entries = 0;
482
	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;
483

484
	for (i = 0; i < nr_desc; i++) {
485
		efi_memory_desc_t *d;
486
		unsigned int e820_type = 0;
487
		unsigned long m = efi->efi_memmap;
488

489
#ifdef CONFIG_X86_64
490
		m |= (u64)efi->efi_memmap_hi << 32;
491
#endif
492

493
		d = efi_memdesc_ptr(m, efi->efi_memdesc_size, i);
494
		switch (d->type) {
495
		case EFI_RESERVED_TYPE:
496
		case EFI_RUNTIME_SERVICES_CODE:
497
		case EFI_RUNTIME_SERVICES_DATA:
498
		case EFI_MEMORY_MAPPED_IO:
499
		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
500
		case EFI_PAL_CODE:
501
			e820_type = E820_TYPE_RESERVED;
502
			break;
503

504
		case EFI_UNUSABLE_MEMORY:
505
			e820_type = E820_TYPE_UNUSABLE;
506
			break;
507

508
		case EFI_ACPI_RECLAIM_MEMORY:
509
			e820_type = E820_TYPE_ACPI;
510
			break;
511

512
		case EFI_LOADER_CODE:
513
		case EFI_LOADER_DATA:
514
		case EFI_BOOT_SERVICES_CODE:
515
		case EFI_BOOT_SERVICES_DATA:
516
		case EFI_CONVENTIONAL_MEMORY:
517
			if (efi_soft_reserve_enabled() &&
518
			    (d->attribute & EFI_MEMORY_SP))
519
				e820_type = E820_TYPE_SOFT_RESERVED;
520
			else
521
				e820_type = E820_TYPE_RAM;
522
			break;
523

524
		case EFI_ACPI_MEMORY_NVS:
525
			e820_type = E820_TYPE_NVS;
526
			break;
527

528
		case EFI_PERSISTENT_MEMORY:
529
			e820_type = E820_TYPE_PMEM;
530
			break;
531

532
		case EFI_UNACCEPTED_MEMORY:
533
			if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))
534
				continue;
535
			e820_type = E820_TYPE_RAM;
536
			process_unaccepted_memory(d->phys_addr,
537
						  d->phys_addr + PAGE_SIZE * d->num_pages);
538
			break;
539
		default:
540
			continue;
541
		}
542

543
		/* Merge adjacent mappings */
544
		if (prev && prev->type == e820_type &&
545
		    (prev->addr + prev->size) == d->phys_addr) {
546
			prev->size += d->num_pages << 12;
547
			continue;
548
		}
549

550
		if (nr_entries == ARRAY_SIZE(params->e820_table)) {
551
			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +
552
				   sizeof(struct setup_data);
553

554
			if (!e820ext || e820ext_size < need)
555
				return EFI_BUFFER_TOO_SMALL;
556

557
			/* boot_params map full, switch to e820 extended */
558
			entry = (struct boot_e820_entry *)e820ext->data;
559
		}
560

561
		entry->addr = d->phys_addr;
562
		entry->size = d->num_pages << PAGE_SHIFT;
563
		entry->type = e820_type;
564
		prev = entry++;
565
		nr_entries++;
566
	}
567

568
	if (nr_entries > ARRAY_SIZE(params->e820_table)) {
569
		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);
570

571
		add_e820ext(params, e820ext, nr_e820ext);
572
		nr_entries -= nr_e820ext;
573
	}
574

575
	params->e820_entries = (u8)nr_entries;
576

577
	return EFI_SUCCESS;
578
}
579

580
static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,
581
				  u32 *e820ext_size)
582
{
583
	efi_status_t status;
584
	unsigned long size;
585

586
	size = sizeof(struct setup_data) +
587
		sizeof(struct e820_entry) * nr_desc;
588

589
	if (*e820ext) {
590
		efi_bs_call(free_pool, *e820ext);
591
		*e820ext = NULL;
592
		*e820ext_size = 0;
593
	}
594

595
	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,
596
			     (void **)e820ext);
597
	if (status == EFI_SUCCESS)
598
		*e820ext_size = size;
599

600
	return status;
601
}
602

603
static efi_status_t allocate_e820(struct boot_params *params,
604
				  struct setup_data **e820ext,
605
				  u32 *e820ext_size)
606
{
607
	struct efi_boot_memmap *map __free(efi_pool) = NULL;
608
	efi_status_t status;
609
	__u32 nr_desc;
610

611
	status = efi_get_memory_map(&map, false);
612
	if (status != EFI_SUCCESS)
613
		return status;
614

615
	nr_desc = map->map_size / map->desc_size;
616
	if (nr_desc > ARRAY_SIZE(params->e820_table) - EFI_MMAP_NR_SLACK_SLOTS) {
617
		u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table) +
618
				 EFI_MMAP_NR_SLACK_SLOTS;
619

620
		status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);
621
		if (status != EFI_SUCCESS)
622
			return status;
623
	}
624

625
	if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))
626
		return allocate_unaccepted_bitmap(nr_desc, map);
627

628
	return EFI_SUCCESS;
629
}
630

631
struct exit_boot_struct {
632
	struct boot_params	*boot_params;
633
	struct efi_info		*efi;
634
};
635

636
static efi_status_t exit_boot_func(struct efi_boot_memmap *map,
637
				   void *priv)
638
{
639
	const char *signature;
640
	struct exit_boot_struct *p = priv;
641

642
	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE
643
				   : EFI32_LOADER_SIGNATURE;
644
	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));
645

646
	efi_set_u64_split((unsigned long)efi_system_table,
647
			  &p->efi->efi_systab, &p->efi->efi_systab_hi);
648
	p->efi->efi_memdesc_size	= map->desc_size;
649
	p->efi->efi_memdesc_version	= map->desc_ver;
650
	efi_set_u64_split((unsigned long)map->map,
651
			  &p->efi->efi_memmap, &p->efi->efi_memmap_hi);
652
	p->efi->efi_memmap_size		= map->map_size;
653

654
	return EFI_SUCCESS;
655
}
656

657
static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)
658
{
659
	struct setup_data *e820ext = NULL;
660
	__u32 e820ext_size = 0;
661
	efi_status_t status;
662
	struct exit_boot_struct priv;
663

664
	priv.boot_params	= boot_params;
665
	priv.efi		= &boot_params->efi_info;
666

667
	status = allocate_e820(boot_params, &e820ext, &e820ext_size);
668
	if (status != EFI_SUCCESS)
669
		return status;
670

671
	/* Might as well exit boot services now */
672
	status = efi_exit_boot_services(handle, &priv, exit_boot_func);
673
	if (status != EFI_SUCCESS)
674
		return status;
675

676
	/* Historic? */
677
	boot_params->alt_mem_k	= 32 * 1024;
678

679
	status = setup_e820(boot_params, e820ext, e820ext_size);
680
	if (status != EFI_SUCCESS)
681
		return status;
682

683
	return EFI_SUCCESS;
684
}
685

686
static bool have_unsupported_snp_features(void)
687
{
688
	u64 unsupported;
689

690
	unsupported = snp_get_unsupported_features(sev_get_status());
691
	if (unsupported) {
692
		efi_err("Unsupported SEV-SNP features detected: 0x%llx\n",
693
			unsupported);
694
		return true;
695
	}
696
	return false;
697
}
698

699
static void efi_get_seed(void *seed, int size)
700
{
701
	efi_get_random_bytes(size, seed);
702

703
	/*
704
	 * This only updates seed[0] when running on 32-bit, but in that case,
705
	 * seed[1] is not used anyway, as there is no virtual KASLR on 32-bit.
706
	 */
707
	*(unsigned long *)seed ^= kaslr_get_random_long("EFI");
708
}
709

710
static void error(char *str)
711
{
712
	efi_warn("Decompression failed: %s\n", str);
713
}
714

715
static const char *cmdline_memmap_override;
716

717
static efi_status_t parse_options(const char *cmdline)
718
{
719
	static const char opts[][14] = {
720
		"mem=", "memmap=", "hugepages="
721
	};
722

723
	for (int i = 0; i < ARRAY_SIZE(opts); i++) {
724
		const char *p = strstr(cmdline, opts[i]);
725

726
		if (p == cmdline || (p > cmdline && isspace(p[-1]))) {
727
			cmdline_memmap_override = opts[i];
728
			break;
729
		}
730
	}
731

732
	return efi_parse_options(cmdline);
733
}
734

735
static efi_status_t efi_decompress_kernel(unsigned long *kernel_entry,
736
					  struct boot_params *boot_params)
737
{
738
	unsigned long virt_addr = LOAD_PHYSICAL_ADDR;
739
	unsigned long addr, alloc_size, entry;
740
	efi_status_t status;
741
	u32 seed[2] = {};
742

743
	boot_params_ptr	= boot_params;
744

745
	/* determine the required size of the allocation */
746
	alloc_size = ALIGN(max_t(unsigned long, output_len, kernel_total_size),
747
			   MIN_KERNEL_ALIGN);
748

749
	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && !efi_nokaslr) {
750
		u64 range = KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR - kernel_total_size;
751
		static const efi_char16_t ami[] = L"American Megatrends";
752

753
		efi_get_seed(seed, sizeof(seed));
754

755
		virt_addr += (range * seed[1]) >> 32;
756
		virt_addr &= ~(CONFIG_PHYSICAL_ALIGN - 1);
757

758
		/*
759
		 * Older Dell systems with AMI UEFI firmware v2.0 may hang
760
		 * while decompressing the kernel if physical address
761
		 * randomization is enabled.
762
		 *
763
		 * https://bugzilla.kernel.org/show_bug.cgi?id=218173
764
		 */
765
		if (efi_system_table->hdr.revision <= EFI_2_00_SYSTEM_TABLE_REVISION &&
766
		    !memcmp(efistub_fw_vendor(), ami, sizeof(ami))) {
767
			efi_debug("AMI firmware v2.0 or older detected - disabling physical KASLR\n");
768
			seed[0] = 0;
769
		} else if (cmdline_memmap_override) {
770
			efi_info("%s detected on the kernel command line - disabling physical KASLR\n",
771
				 cmdline_memmap_override);
772
			seed[0] = 0;
773
		}
774

775
		boot_params->hdr.loadflags |= KASLR_FLAG;
776
	}
777

778
	status = efi_random_alloc(alloc_size, CONFIG_PHYSICAL_ALIGN, &addr,
779
				  seed[0], EFI_LOADER_CODE,
780
				  LOAD_PHYSICAL_ADDR,
781
				  EFI_X86_KERNEL_ALLOC_LIMIT);
782
	if (status != EFI_SUCCESS)
783
		return status;
784

785
	entry = decompress_kernel((void *)addr, virt_addr, error);
786
	if (entry == ULONG_MAX) {
787
		efi_free(alloc_size, addr);
788
		return EFI_LOAD_ERROR;
789
	}
790

791
	*kernel_entry = addr + entry;
792

793
	return efi_adjust_memory_range_protection(addr, kernel_text_size) ?:
794
	       efi_adjust_memory_range_protection(addr + kernel_inittext_offset,
795
						  kernel_inittext_size);
796
}
797

798
static void __noreturn enter_kernel(unsigned long kernel_addr,
799
				    struct boot_params *boot_params)
800
{
801
	/* enter decompressed kernel with boot_params pointer in RSI/ESI */
802
	asm("jmp *%0"::"r"(kernel_addr), "S"(boot_params));
803

804
	unreachable();
805
}
806

807
/*
808
 * On success, this routine will jump to the relocated image directly and never
809
 * return.  On failure, it will exit to the firmware via efi_exit() instead of
810
 * returning.
811
 */
812
void __noreturn efi_stub_entry(efi_handle_t handle,
813
			       efi_system_table_t *sys_table_arg,
814
			       struct boot_params *boot_params)
815

816
{
817
	efi_guid_t guid = EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID;
818
	const struct linux_efi_initrd *initrd = NULL;
819
	unsigned long kernel_entry;
820
	struct setup_header *hdr;
821
	efi_status_t status;
822

823
	efi_system_table = sys_table_arg;
824
	/* Check if we were booted by the EFI firmware */
825
	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
826
		efi_exit(handle, EFI_INVALID_PARAMETER);
827

828
	if (!IS_ENABLED(CONFIG_EFI_HANDOVER_PROTOCOL) || !boot_params) {
829
		status = efi_allocate_bootparams(handle, &boot_params);
830
		if (status != EFI_SUCCESS)
831
			efi_exit(handle, status);
832
	}
833

834
	hdr = &boot_params->hdr;
835

836
	if (have_unsupported_snp_features())
837
		efi_exit(handle, EFI_UNSUPPORTED);
838

839
	if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) {
840
		efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);
841
		if (efi_dxe_table &&
842
		    efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {
843
			efi_warn("Ignoring DXE services table: invalid signature\n");
844
			efi_dxe_table = NULL;
845
		}
846
	}
847

848
	/* grab the memory attributes protocol if it exists */
849
	efi_bs_call(locate_protocol, &guid, NULL, (void **)&memattr);
850

851
	status = efi_setup_5level_paging();
852
	if (status != EFI_SUCCESS) {
853
		efi_err("efi_setup_5level_paging() failed!\n");
854
		goto fail;
855
	}
856

857
#ifdef CONFIG_CMDLINE_BOOL
858
	status = parse_options(CONFIG_CMDLINE);
859
	if (status != EFI_SUCCESS) {
860
		efi_err("Failed to parse options\n");
861
		goto fail;
862
	}
863
#endif
864
	if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
865
		unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr |
866
					       ((u64)boot_params->ext_cmd_line_ptr << 32));
867
		status = parse_options((char *)cmdline_paddr);
868
		if (status != EFI_SUCCESS) {
869
			efi_err("Failed to parse options\n");
870
			goto fail;
871
		}
872
	}
873

874
	if (efi_mem_encrypt > 0)
875
		hdr->xloadflags |= XLF_MEM_ENCRYPTION;
876

877
	status = efi_decompress_kernel(&kernel_entry, boot_params);
878
	if (status != EFI_SUCCESS) {
879
		efi_err("Failed to decompress kernel\n");
880
		goto fail;
881
	}
882

883
	/*
884
	 * At this point, an initrd may already have been loaded by the
885
	 * bootloader and passed via bootparams. We permit an initrd loaded
886
	 * from the LINUX_EFI_INITRD_MEDIA_GUID device path to supersede it.
887
	 *
888
	 * If the device path is not present, any command-line initrd=
889
	 * arguments will be processed only if image is not NULL, which will be
890
	 * the case only if we were loaded via the PE entry point.
891
	 */
892
	status = efi_load_initrd(image, hdr->initrd_addr_max, ULONG_MAX,
893
				 &initrd);
894
	if (status != EFI_SUCCESS)
895
		goto fail;
896
	if (initrd && initrd->size > 0) {
897
		efi_set_u64_split(initrd->base, &hdr->ramdisk_image,
898
				  &boot_params->ext_ramdisk_image);
899
		efi_set_u64_split(initrd->size, &hdr->ramdisk_size,
900
				  &boot_params->ext_ramdisk_size);
901
	}
902

903

904
	/*
905
	 * If the boot loader gave us a value for secure_boot then we use that,
906
	 * otherwise we ask the BIOS.
907
	 */
908
	if (boot_params->secure_boot == efi_secureboot_mode_unset)
909
		boot_params->secure_boot = efi_get_secureboot();
910

911
	/* Ask the firmware to clear memory on unclean shutdown */
912
	efi_enable_reset_attack_mitigation();
913

914
	efi_random_get_seed();
915

916
	efi_retrieve_eventlog();
917

918
	setup_graphics(boot_params);
919

920
	setup_efi_pci(boot_params);
921

922
	setup_quirks(boot_params);
923

924
	setup_unaccepted_memory();
925

926
	status = exit_boot(boot_params, handle);
927
	if (status != EFI_SUCCESS) {
928
		efi_err("exit_boot() failed!\n");
929
		goto fail;
930
	}
931

932
	/*
933
	 * Call the SEV init code while still running with the firmware's
934
	 * GDT/IDT, so #VC exceptions will be handled by EFI.
935
	 */
936
	sev_enable(boot_params);
937

938
	efi_5level_switch();
939

940
	enter_kernel(kernel_entry, boot_params);
941
fail:
942
	efi_err("efi_stub_entry() failed!\n");
943

944
	efi_exit(handle, status);
945
}
946

947
efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
948
				   efi_system_table_t *sys_table_arg)
949
{
950
	efi_stub_entry(handle, sys_table_arg, NULL);
951
}
952

953
#ifdef CONFIG_EFI_HANDOVER_PROTOCOL
954
void efi_handover_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg,
955
			struct boot_params *boot_params)
956
{
957
	memset(_bss, 0, _ebss - _bss);
958
	efi_stub_entry(handle, sys_table_arg, boot_params);
959
}
960

961
#ifndef CONFIG_EFI_MIXED
962
extern __alias(efi_handover_entry)
963
void efi32_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg,
964
		      struct boot_params *boot_params);
965

966
extern __alias(efi_handover_entry)
967
void efi64_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg,
968
		      struct boot_params *boot_params);
969
#endif
970
#endif
971

972