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1// SPDX-License-Identifier: GPL-2.0-only2 3/* -----------------------------------------------------------------------4 *5 *   Copyright 2011 Intel Corporation; author Matt Fleming6 *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 24extern char _bss[], _ebss[];25 26const efi_system_table_t *efi_system_table;27const efi_dxe_services_table_t *efi_dxe_table;28static efi_loaded_image_t *image = NULL;29static efi_memory_attribute_protocol_t *memattr;30 31typedef union sev_memory_acceptance_protocol sev_memory_acceptance_protocol_t;32union 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 42static efi_status_t43preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom)44{45	struct pci_setup_rom *rom = 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 where53	 * the romimage and romsize fields are supposed to be. Typically the EFI54	 * code is mapped at high addresses, translating to an unrealistically55	 * large romsize. The UEFI spec limits the size of option ROMs to 1656	 * 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	*__rom = rom;79 80	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,81				PCI_VENDOR_ID, 1, &rom->vendor);82 83	if (status != EFI_SUCCESS) {84		efi_err("Failed to read rom->vendor\n");85		goto free_struct;86	}87 88	status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16,89				PCI_DEVICE_ID, 1, &rom->devid);90 91	if (status != EFI_SUCCESS) {92		efi_err("Failed to read rom->devid\n");93		goto free_struct;94	}95 96	status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus,97				&rom->device, &rom->function);98 99	if (status != EFI_SUCCESS)100		goto free_struct;101 102	memcpy(rom->romdata, romimage, romsize);103	return status;104 105free_struct:106	efi_bs_call(free_pool, rom);107	return status;108}109 110/*111 * There's no way to return an informative status from this function,112 * because any analysis (and printing of error messages) needs to be113 * done directly at the EFI function call-site.114 *115 * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we116 * just didn't find any PCI devices, but there's no way to tell outside117 * the context of the call.118 */119static void setup_efi_pci(struct boot_params *params)120{121	efi_status_t status;122	void **pci_handle = NULL;123	efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID;124	unsigned long size = 0;125	struct setup_data *data;126	efi_handle_t h;127	int i;128 129	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,130			     &pci_proto, NULL, &size, pci_handle);131 132	if (status == EFI_BUFFER_TOO_SMALL) {133		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,134				     (void **)&pci_handle);135 136		if (status != EFI_SUCCESS) {137			efi_err("Failed to allocate memory for 'pci_handle'\n");138			return;139		}140 141		status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,142				     &pci_proto, NULL, &size, pci_handle);143	}144 145	if (status != EFI_SUCCESS)146		goto free_handle;147 148	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;149 150	while (data && data->next)151		data = (struct setup_data *)(unsigned long)data->next;152 153	for_each_efi_handle(h, pci_handle, size, i) {154		efi_pci_io_protocol_t *pci = NULL;155		struct pci_setup_rom *rom;156 157		status = efi_bs_call(handle_protocol, h, &pci_proto,158				     (void **)&pci);159		if (status != EFI_SUCCESS || !pci)160			continue;161 162		status = preserve_pci_rom_image(pci, &rom);163		if (status != EFI_SUCCESS)164			continue;165 166		if (data)167			data->next = (unsigned long)rom;168		else169			params->hdr.setup_data = (unsigned long)rom;170 171		data = (struct setup_data *)rom;172	}173 174free_handle:175	efi_bs_call(free_pool, pci_handle);176}177 178static void retrieve_apple_device_properties(struct boot_params *boot_params)179{180	efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID;181	struct setup_data *data, *new;182	efi_status_t status;183	u32 size = 0;184	apple_properties_protocol_t *p;185 186	status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p);187	if (status != EFI_SUCCESS)188		return;189 190	if (efi_table_attr(p, version) != 0x10000) {191		efi_err("Unsupported properties proto version\n");192		return;193	}194 195	efi_call_proto(p, get_all, NULL, &size);196	if (!size)197		return;198 199	do {200		status = efi_bs_call(allocate_pool, EFI_LOADER_DATA,201				     size + sizeof(struct setup_data),202				     (void **)&new);203		if (status != EFI_SUCCESS) {204			efi_err("Failed to allocate memory for 'properties'\n");205			return;206		}207 208		status = efi_call_proto(p, get_all, new->data, &size);209 210		if (status == EFI_BUFFER_TOO_SMALL)211			efi_bs_call(free_pool, new);212	} while (status == EFI_BUFFER_TOO_SMALL);213 214	new->type = SETUP_APPLE_PROPERTIES;215	new->len  = size;216	new->next = 0;217 218	data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data;219	if (!data) {220		boot_params->hdr.setup_data = (unsigned long)new;221	} else {222		while (data->next)223			data = (struct setup_data *)(unsigned long)data->next;224		data->next = (unsigned long)new;225	}226}227 228static bool apple_match_product_name(void)229{230	static const char type1_product_matches[][15] = {231		"MacBookPro11,3",232		"MacBookPro11,5",233		"MacBookPro13,3",234		"MacBookPro14,3",235		"MacBookPro15,1",236		"MacBookPro15,3",237		"MacBookPro16,1",238		"MacBookPro16,4",239	};240	const struct efi_smbios_type1_record *record;241	const u8 *product;242 243	record = (struct efi_smbios_type1_record *)efi_get_smbios_record(1);244	if (!record)245		return false;246 247	product = efi_get_smbios_string(record, product_name);248	if (!product)249		return false;250 251	for (int i = 0; i < ARRAY_SIZE(type1_product_matches); i++) {252		if (!strcmp(product, type1_product_matches[i]))253			return true;254	}255 256	return false;257}258 259static void apple_set_os(void)260{261	struct {262		unsigned long version;263		efi_status_t (__efiapi *set_os_version)(const char *);264		efi_status_t (__efiapi *set_os_vendor)(const char *);265	} *set_os;266	efi_status_t status;267 268	if (!efi_is_64bit() || !apple_match_product_name())269		return;270 271	status = efi_bs_call(locate_protocol, &APPLE_SET_OS_PROTOCOL_GUID, NULL,272			     (void **)&set_os);273	if (status != EFI_SUCCESS)274		return;275 276	if (set_os->version >= 2) {277		status = set_os->set_os_vendor("Apple Inc.");278		if (status != EFI_SUCCESS)279			efi_err("Failed to set OS vendor via apple_set_os\n");280	}281 282	if (set_os->version > 0) {283		/* The version being set doesn't seem to matter */284		status = set_os->set_os_version("Mac OS X 10.9");285		if (status != EFI_SUCCESS)286			efi_err("Failed to set OS version via apple_set_os\n");287	}288}289 290efi_status_t efi_adjust_memory_range_protection(unsigned long start,291						unsigned long size)292{293	efi_status_t status;294	efi_gcd_memory_space_desc_t desc;295	unsigned long end, next;296	unsigned long rounded_start, rounded_end;297	unsigned long unprotect_start, unprotect_size;298 299	rounded_start = rounddown(start, EFI_PAGE_SIZE);300	rounded_end = roundup(start + size, EFI_PAGE_SIZE);301 302	if (memattr != NULL) {303		status = efi_call_proto(memattr, set_memory_attributes,304					rounded_start,305					rounded_end - rounded_start,306					EFI_MEMORY_RO);307		if (status != EFI_SUCCESS) {308			efi_warn("Failed to set EFI_MEMORY_RO attribute\n");309			return status;310		}311 312		status = efi_call_proto(memattr, clear_memory_attributes,313					rounded_start,314					rounded_end - rounded_start,315					EFI_MEMORY_XP);316		if (status != EFI_SUCCESS)317			efi_warn("Failed to clear EFI_MEMORY_XP attribute\n");318		return status;319	}320 321	if (efi_dxe_table == NULL)322		return EFI_SUCCESS;323 324	/*325	 * Don't modify memory region attributes, they are326	 * already suitable, to lower the possibility to327	 * encounter firmware bugs.328	 */329 330	for (end = start + size; start < end; start = next) {331 332		status = efi_dxe_call(get_memory_space_descriptor, start, &desc);333 334		if (status != EFI_SUCCESS)335			break;336 337		next = desc.base_address + desc.length;338 339		/*340		 * Only system memory is suitable for trampoline/kernel image placement,341		 * so only this type of memory needs its attributes to be modified.342		 */343 344		if (desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory ||345		    (desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0)346			continue;347 348		unprotect_start = max(rounded_start, (unsigned long)desc.base_address);349		unprotect_size = min(rounded_end, next) - unprotect_start;350 351		status = efi_dxe_call(set_memory_space_attributes,352				      unprotect_start, unprotect_size,353				      EFI_MEMORY_WB);354 355		if (status != EFI_SUCCESS) {356			efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n",357				 unprotect_start,358				 unprotect_start + unprotect_size,359				 status);360			break;361		}362	}363	return EFI_SUCCESS;364}365 366static void setup_unaccepted_memory(void)367{368	efi_guid_t mem_acceptance_proto = OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL_GUID;369	sev_memory_acceptance_protocol_t *proto;370	efi_status_t status;371 372	if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))373		return;374 375	/*376	 * Enable unaccepted memory before calling exit boot services in order377	 * for the UEFI to not accept all memory on EBS.378	 */379	status = efi_bs_call(locate_protocol, &mem_acceptance_proto, NULL,380			     (void **)&proto);381	if (status != EFI_SUCCESS)382		return;383 384	status = efi_call_proto(proto, allow_unaccepted_memory);385	if (status != EFI_SUCCESS)386		efi_err("Memory acceptance protocol failed\n");387}388 389static efi_char16_t *efistub_fw_vendor(void)390{391	unsigned long vendor = efi_table_attr(efi_system_table, fw_vendor);392 393	return (efi_char16_t *)vendor;394}395 396static const efi_char16_t apple[] = L"Apple";397 398static void setup_quirks(struct boot_params *boot_params)399{400	if (!memcmp(efistub_fw_vendor(), apple, sizeof(apple))) {401		if (IS_ENABLED(CONFIG_APPLE_PROPERTIES))402			retrieve_apple_device_properties(boot_params);403 404		apple_set_os();405	}406}407 408/*409 * See if we have Universal Graphics Adapter (UGA) protocol410 */411static efi_status_t412setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size)413{414	efi_status_t status;415	u32 width, height;416	void **uga_handle = NULL;417	efi_uga_draw_protocol_t *uga = NULL, *first_uga;418	efi_handle_t handle;419	int i;420 421	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,422			     (void **)&uga_handle);423	if (status != EFI_SUCCESS)424		return status;425 426	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,427			     uga_proto, NULL, &size, uga_handle);428	if (status != EFI_SUCCESS)429		goto free_handle;430 431	height = 0;432	width = 0;433 434	first_uga = NULL;435	for_each_efi_handle(handle, uga_handle, size, i) {436		efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID;437		u32 w, h, depth, refresh;438		void *pciio;439 440		status = efi_bs_call(handle_protocol, handle, uga_proto,441				     (void **)&uga);442		if (status != EFI_SUCCESS)443			continue;444 445		pciio = NULL;446		efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio);447 448		status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh);449		if (status == EFI_SUCCESS && (!first_uga || pciio)) {450			width = w;451			height = h;452 453			/*454			 * Once we've found a UGA supporting PCIIO,455			 * don't bother looking any further.456			 */457			if (pciio)458				break;459 460			first_uga = uga;461		}462	}463 464	if (!width && !height)465		goto free_handle;466 467	/* EFI framebuffer */468	si->orig_video_isVGA	= VIDEO_TYPE_EFI;469 470	si->lfb_depth		= 32;471	si->lfb_width		= width;472	si->lfb_height		= height;473 474	si->red_size		= 8;475	si->red_pos		= 16;476	si->green_size		= 8;477	si->green_pos		= 8;478	si->blue_size		= 8;479	si->blue_pos		= 0;480	si->rsvd_size		= 8;481	si->rsvd_pos		= 24;482 483free_handle:484	efi_bs_call(free_pool, uga_handle);485 486	return status;487}488 489static void setup_graphics(struct boot_params *boot_params)490{491	efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;492	struct screen_info *si;493	efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;494	efi_status_t status;495	unsigned long size;496	void **gop_handle = NULL;497	void **uga_handle = NULL;498 499	si = &boot_params->screen_info;500	memset(si, 0, sizeof(*si));501 502	size = 0;503	status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,504			     &graphics_proto, NULL, &size, gop_handle);505	if (status == EFI_BUFFER_TOO_SMALL)506		status = efi_setup_gop(si, &graphics_proto, size);507 508	if (status != EFI_SUCCESS) {509		size = 0;510		status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL,511				     &uga_proto, NULL, &size, uga_handle);512		if (status == EFI_BUFFER_TOO_SMALL)513			setup_uga(si, &uga_proto, size);514	}515}516 517 518static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status)519{520	efi_bs_call(exit, handle, status, 0, NULL);521	for(;;)522		asm("hlt");523}524 525void __noreturn efi_stub_entry(efi_handle_t handle,526			       efi_system_table_t *sys_table_arg,527			       struct boot_params *boot_params);528 529/*530 * Because the x86 boot code expects to be passed a boot_params we531 * need to create one ourselves (usually the bootloader would create532 * one for us).533 */534efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,535				   efi_system_table_t *sys_table_arg)536{537	efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID;538	struct boot_params *boot_params;539	struct setup_header *hdr;540	int options_size = 0;541	efi_status_t status;542	unsigned long alloc;543	char *cmdline_ptr;544 545	efi_system_table = sys_table_arg;546 547	/* Check if we were booted by the EFI firmware */548	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)549		efi_exit(handle, EFI_INVALID_PARAMETER);550 551	status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image);552	if (status != EFI_SUCCESS) {553		efi_err("Failed to get handle for LOADED_IMAGE_PROTOCOL\n");554		efi_exit(handle, status);555	}556 557	status = efi_allocate_pages(PARAM_SIZE, &alloc, ULONG_MAX);558	if (status != EFI_SUCCESS)559		efi_exit(handle, status);560 561	boot_params = memset((void *)alloc, 0x0, PARAM_SIZE);562	hdr	    = &boot_params->hdr;563 564	/* Assign the setup_header fields that the kernel actually cares about */565	hdr->root_flags	= 1;566	hdr->vid_mode	= 0xffff;567 568	hdr->type_of_loader = 0x21;569	hdr->initrd_addr_max = INT_MAX;570 571	/* Convert unicode cmdline to ascii */572	cmdline_ptr = efi_convert_cmdline(image, &options_size);573	if (!cmdline_ptr) {574		efi_free(PARAM_SIZE, alloc);575		efi_exit(handle, EFI_OUT_OF_RESOURCES);576	}577 578	efi_set_u64_split((unsigned long)cmdline_ptr, &hdr->cmd_line_ptr,579			  &boot_params->ext_cmd_line_ptr);580 581	efi_stub_entry(handle, sys_table_arg, boot_params);582	/* not reached */583}584 585static void add_e820ext(struct boot_params *params,586			struct setup_data *e820ext, u32 nr_entries)587{588	struct setup_data *data;589 590	e820ext->type = SETUP_E820_EXT;591	e820ext->len  = nr_entries * sizeof(struct boot_e820_entry);592	e820ext->next = 0;593 594	data = (struct setup_data *)(unsigned long)params->hdr.setup_data;595 596	while (data && data->next)597		data = (struct setup_data *)(unsigned long)data->next;598 599	if (data)600		data->next = (unsigned long)e820ext;601	else602		params->hdr.setup_data = (unsigned long)e820ext;603}604 605static efi_status_t606setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size)607{608	struct boot_e820_entry *entry = params->e820_table;609	struct efi_info *efi = &params->efi_info;610	struct boot_e820_entry *prev = NULL;611	u32 nr_entries;612	u32 nr_desc;613	int i;614 615	nr_entries = 0;616	nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size;617 618	for (i = 0; i < nr_desc; i++) {619		efi_memory_desc_t *d;620		unsigned int e820_type = 0;621		unsigned long m = efi->efi_memmap;622 623#ifdef CONFIG_X86_64624		m |= (u64)efi->efi_memmap_hi << 32;625#endif626 627		d = efi_memdesc_ptr(m, efi->efi_memdesc_size, i);628		switch (d->type) {629		case EFI_RESERVED_TYPE:630		case EFI_RUNTIME_SERVICES_CODE:631		case EFI_RUNTIME_SERVICES_DATA:632		case EFI_MEMORY_MAPPED_IO:633		case EFI_MEMORY_MAPPED_IO_PORT_SPACE:634		case EFI_PAL_CODE:635			e820_type = E820_TYPE_RESERVED;636			break;637 638		case EFI_UNUSABLE_MEMORY:639			e820_type = E820_TYPE_UNUSABLE;640			break;641 642		case EFI_ACPI_RECLAIM_MEMORY:643			e820_type = E820_TYPE_ACPI;644			break;645 646		case EFI_LOADER_CODE:647		case EFI_LOADER_DATA:648		case EFI_BOOT_SERVICES_CODE:649		case EFI_BOOT_SERVICES_DATA:650		case EFI_CONVENTIONAL_MEMORY:651			if (efi_soft_reserve_enabled() &&652			    (d->attribute & EFI_MEMORY_SP))653				e820_type = E820_TYPE_SOFT_RESERVED;654			else655				e820_type = E820_TYPE_RAM;656			break;657 658		case EFI_ACPI_MEMORY_NVS:659			e820_type = E820_TYPE_NVS;660			break;661 662		case EFI_PERSISTENT_MEMORY:663			e820_type = E820_TYPE_PMEM;664			break;665 666		case EFI_UNACCEPTED_MEMORY:667			if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))668				continue;669			e820_type = E820_TYPE_RAM;670			process_unaccepted_memory(d->phys_addr,671						  d->phys_addr + PAGE_SIZE * d->num_pages);672			break;673		default:674			continue;675		}676 677		/* Merge adjacent mappings */678		if (prev && prev->type == e820_type &&679		    (prev->addr + prev->size) == d->phys_addr) {680			prev->size += d->num_pages << 12;681			continue;682		}683 684		if (nr_entries == ARRAY_SIZE(params->e820_table)) {685			u32 need = (nr_desc - i) * sizeof(struct e820_entry) +686				   sizeof(struct setup_data);687 688			if (!e820ext || e820ext_size < need)689				return EFI_BUFFER_TOO_SMALL;690 691			/* boot_params map full, switch to e820 extended */692			entry = (struct boot_e820_entry *)e820ext->data;693		}694 695		entry->addr = d->phys_addr;696		entry->size = d->num_pages << PAGE_SHIFT;697		entry->type = e820_type;698		prev = entry++;699		nr_entries++;700	}701 702	if (nr_entries > ARRAY_SIZE(params->e820_table)) {703		u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table);704 705		add_e820ext(params, e820ext, nr_e820ext);706		nr_entries -= nr_e820ext;707	}708 709	params->e820_entries = (u8)nr_entries;710 711	return EFI_SUCCESS;712}713 714static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext,715				  u32 *e820ext_size)716{717	efi_status_t status;718	unsigned long size;719 720	size = sizeof(struct setup_data) +721		sizeof(struct e820_entry) * nr_desc;722 723	if (*e820ext) {724		efi_bs_call(free_pool, *e820ext);725		*e820ext = NULL;726		*e820ext_size = 0;727	}728 729	status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size,730			     (void **)e820ext);731	if (status == EFI_SUCCESS)732		*e820ext_size = size;733 734	return status;735}736 737static efi_status_t allocate_e820(struct boot_params *params,738				  struct setup_data **e820ext,739				  u32 *e820ext_size)740{741	struct efi_boot_memmap *map;742	efi_status_t status;743	__u32 nr_desc;744 745	status = efi_get_memory_map(&map, false);746	if (status != EFI_SUCCESS)747		return status;748 749	nr_desc = map->map_size / map->desc_size;750	if (nr_desc > ARRAY_SIZE(params->e820_table) - EFI_MMAP_NR_SLACK_SLOTS) {751		u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table) +752				 EFI_MMAP_NR_SLACK_SLOTS;753 754		status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size);755	}756 757	if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && status == EFI_SUCCESS)758		status = allocate_unaccepted_bitmap(nr_desc, map);759 760	efi_bs_call(free_pool, map);761	return status;762}763 764struct exit_boot_struct {765	struct boot_params	*boot_params;766	struct efi_info		*efi;767};768 769static efi_status_t exit_boot_func(struct efi_boot_memmap *map,770				   void *priv)771{772	const char *signature;773	struct exit_boot_struct *p = priv;774 775	signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE776				   : EFI32_LOADER_SIGNATURE;777	memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32));778 779	efi_set_u64_split((unsigned long)efi_system_table,780			  &p->efi->efi_systab, &p->efi->efi_systab_hi);781	p->efi->efi_memdesc_size	= map->desc_size;782	p->efi->efi_memdesc_version	= map->desc_ver;783	efi_set_u64_split((unsigned long)map->map,784			  &p->efi->efi_memmap, &p->efi->efi_memmap_hi);785	p->efi->efi_memmap_size		= map->map_size;786 787	return EFI_SUCCESS;788}789 790static efi_status_t exit_boot(struct boot_params *boot_params, void *handle)791{792	struct setup_data *e820ext = NULL;793	__u32 e820ext_size = 0;794	efi_status_t status;795	struct exit_boot_struct priv;796 797	priv.boot_params	= boot_params;798	priv.efi		= &boot_params->efi_info;799 800	status = allocate_e820(boot_params, &e820ext, &e820ext_size);801	if (status != EFI_SUCCESS)802		return status;803 804	/* Might as well exit boot services now */805	status = efi_exit_boot_services(handle, &priv, exit_boot_func);806	if (status != EFI_SUCCESS)807		return status;808 809	/* Historic? */810	boot_params->alt_mem_k	= 32 * 1024;811 812	status = setup_e820(boot_params, e820ext, e820ext_size);813	if (status != EFI_SUCCESS)814		return status;815 816	return EFI_SUCCESS;817}818 819static bool have_unsupported_snp_features(void)820{821	u64 unsupported;822 823	unsupported = snp_get_unsupported_features(sev_get_status());824	if (unsupported) {825		efi_err("Unsupported SEV-SNP features detected: 0x%llx\n",826			unsupported);827		return true;828	}829	return false;830}831 832static void efi_get_seed(void *seed, int size)833{834	efi_get_random_bytes(size, seed);835 836	/*837	 * This only updates seed[0] when running on 32-bit, but in that case,838	 * seed[1] is not used anyway, as there is no virtual KASLR on 32-bit.839	 */840	*(unsigned long *)seed ^= kaslr_get_random_long("EFI");841}842 843static void error(char *str)844{845	efi_warn("Decompression failed: %s\n", str);846}847 848static const char *cmdline_memmap_override;849 850static efi_status_t parse_options(const char *cmdline)851{852	static const char opts[][14] = {853		"mem=", "memmap=", "hugepages="854	};855 856	for (int i = 0; i < ARRAY_SIZE(opts); i++) {857		const char *p = strstr(cmdline, opts[i]);858 859		if (p == cmdline || (p > cmdline && isspace(p[-1]))) {860			cmdline_memmap_override = opts[i];861			break;862		}863	}864 865	return efi_parse_options(cmdline);866}867 868static efi_status_t efi_decompress_kernel(unsigned long *kernel_entry)869{870	unsigned long virt_addr = LOAD_PHYSICAL_ADDR;871	unsigned long addr, alloc_size, entry;872	efi_status_t status;873	u32 seed[2] = {};874 875	/* determine the required size of the allocation */876	alloc_size = ALIGN(max_t(unsigned long, output_len, kernel_total_size),877			   MIN_KERNEL_ALIGN);878 879	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && !efi_nokaslr) {880		u64 range = KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR - kernel_total_size;881		static const efi_char16_t ami[] = L"American Megatrends";882 883		efi_get_seed(seed, sizeof(seed));884 885		virt_addr += (range * seed[1]) >> 32;886		virt_addr &= ~(CONFIG_PHYSICAL_ALIGN - 1);887 888		/*889		 * Older Dell systems with AMI UEFI firmware v2.0 may hang890		 * while decompressing the kernel if physical address891		 * randomization is enabled.892		 *893		 * https://bugzilla.kernel.org/show_bug.cgi?id=218173894		 */895		if (efi_system_table->hdr.revision <= EFI_2_00_SYSTEM_TABLE_REVISION &&896		    !memcmp(efistub_fw_vendor(), ami, sizeof(ami))) {897			efi_debug("AMI firmware v2.0 or older detected - disabling physical KASLR\n");898			seed[0] = 0;899		} else if (cmdline_memmap_override) {900			efi_info("%s detected on the kernel command line - disabling physical KASLR\n",901				 cmdline_memmap_override);902			seed[0] = 0;903		}904 905		boot_params_ptr->hdr.loadflags |= KASLR_FLAG;906	}907 908	status = efi_random_alloc(alloc_size, CONFIG_PHYSICAL_ALIGN, &addr,909				  seed[0], EFI_LOADER_CODE,910				  LOAD_PHYSICAL_ADDR,911				  EFI_X86_KERNEL_ALLOC_LIMIT);912	if (status != EFI_SUCCESS)913		return status;914 915	entry = decompress_kernel((void *)addr, virt_addr, error);916	if (entry == ULONG_MAX) {917		efi_free(alloc_size, addr);918		return EFI_LOAD_ERROR;919	}920 921	*kernel_entry = addr + entry;922 923	return efi_adjust_memory_range_protection(addr, kernel_text_size);924}925 926static void __noreturn enter_kernel(unsigned long kernel_addr,927				    struct boot_params *boot_params)928{929	/* enter decompressed kernel with boot_params pointer in RSI/ESI */930	asm("jmp *%0"::"r"(kernel_addr), "S"(boot_params));931 932	unreachable();933}934 935/*936 * On success, this routine will jump to the relocated image directly and never937 * return.  On failure, it will exit to the firmware via efi_exit() instead of938 * returning.939 */940void __noreturn efi_stub_entry(efi_handle_t handle,941			       efi_system_table_t *sys_table_arg,942			       struct boot_params *boot_params)943{944	efi_guid_t guid = EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID;945	struct setup_header *hdr = &boot_params->hdr;946	const struct linux_efi_initrd *initrd = NULL;947	unsigned long kernel_entry;948	efi_status_t status;949 950	boot_params_ptr = boot_params;951 952	efi_system_table = sys_table_arg;953	/* Check if we were booted by the EFI firmware */954	if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)955		efi_exit(handle, EFI_INVALID_PARAMETER);956 957	if (have_unsupported_snp_features())958		efi_exit(handle, EFI_UNSUPPORTED);959 960	if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) {961		efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID);962		if (efi_dxe_table &&963		    efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) {964			efi_warn("Ignoring DXE services table: invalid signature\n");965			efi_dxe_table = NULL;966		}967	}968 969	/* grab the memory attributes protocol if it exists */970	efi_bs_call(locate_protocol, &guid, NULL, (void **)&memattr);971 972	status = efi_setup_5level_paging();973	if (status != EFI_SUCCESS) {974		efi_err("efi_setup_5level_paging() failed!\n");975		goto fail;976	}977 978#ifdef CONFIG_CMDLINE_BOOL979	status = parse_options(CONFIG_CMDLINE);980	if (status != EFI_SUCCESS) {981		efi_err("Failed to parse options\n");982		goto fail;983	}984#endif985	if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {986		unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr |987					       ((u64)boot_params->ext_cmd_line_ptr << 32));988		status = parse_options((char *)cmdline_paddr);989		if (status != EFI_SUCCESS) {990			efi_err("Failed to parse options\n");991			goto fail;992		}993	}994 995	if (efi_mem_encrypt > 0)996		hdr->xloadflags |= XLF_MEM_ENCRYPTION;997 998	status = efi_decompress_kernel(&kernel_entry);999	if (status != EFI_SUCCESS) {1000		efi_err("Failed to decompress kernel\n");1001		goto fail;1002	}1003 1004	/*1005	 * At this point, an initrd may already have been loaded by the1006	 * bootloader and passed via bootparams. We permit an initrd loaded1007	 * from the LINUX_EFI_INITRD_MEDIA_GUID device path to supersede it.1008	 *1009	 * If the device path is not present, any command-line initrd=1010	 * arguments will be processed only if image is not NULL, which will be1011	 * the case only if we were loaded via the PE entry point.1012	 */1013	status = efi_load_initrd(image, hdr->initrd_addr_max, ULONG_MAX,1014				 &initrd);1015	if (status != EFI_SUCCESS)1016		goto fail;1017	if (initrd && initrd->size > 0) {1018		efi_set_u64_split(initrd->base, &hdr->ramdisk_image,1019				  &boot_params->ext_ramdisk_image);1020		efi_set_u64_split(initrd->size, &hdr->ramdisk_size,1021				  &boot_params->ext_ramdisk_size);1022	}1023 1024 1025	/*1026	 * If the boot loader gave us a value for secure_boot then we use that,1027	 * otherwise we ask the BIOS.1028	 */1029	if (boot_params->secure_boot == efi_secureboot_mode_unset)1030		boot_params->secure_boot = efi_get_secureboot();1031 1032	/* Ask the firmware to clear memory on unclean shutdown */1033	efi_enable_reset_attack_mitigation();1034 1035	efi_random_get_seed();1036 1037	efi_retrieve_eventlog();1038 1039	setup_graphics(boot_params);1040 1041	setup_efi_pci(boot_params);1042 1043	setup_quirks(boot_params);1044 1045	setup_unaccepted_memory();1046 1047	status = exit_boot(boot_params, handle);1048	if (status != EFI_SUCCESS) {1049		efi_err("exit_boot() failed!\n");1050		goto fail;1051	}1052 1053	/*1054	 * Call the SEV init code while still running with the firmware's1055	 * GDT/IDT, so #VC exceptions will be handled by EFI.1056	 */1057	sev_enable(boot_params);1058 1059	efi_5level_switch();1060 1061	enter_kernel(kernel_entry, boot_params);1062fail:1063	efi_err("efi_stub_entry() failed!\n");1064 1065	efi_exit(handle, status);1066}1067 1068#ifdef CONFIG_EFI_HANDOVER_PROTOCOL1069void efi_handover_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg,1070			struct boot_params *boot_params)1071{1072	memset(_bss, 0, _ebss - _bss);1073	efi_stub_entry(handle, sys_table_arg, boot_params);1074}1075 1076#ifndef CONFIG_EFI_MIXED1077extern __alias(efi_handover_entry)1078void efi32_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg,1079		      struct boot_params *boot_params);1080 1081extern __alias(efi_handover_entry)1082void efi64_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg,1083		      struct boot_params *boot_params);1084#endif1085#endif1086