| // SPDX-License-Identifier: GPL-2.0-only |
| |
| /* ----------------------------------------------------------------------- |
| * |
| * Copyright 2011 Intel Corporation; author Matt Fleming |
| * |
| * ----------------------------------------------------------------------- */ |
| |
| #include <linux/efi.h> |
| #include <linux/pci.h> |
| #include <linux/stddef.h> |
| |
| #include <asm/efi.h> |
| #include <asm/e820/types.h> |
| #include <asm/setup.h> |
| #include <asm/desc.h> |
| #include <asm/boot.h> |
| #include <asm/kaslr.h> |
| #include <asm/sev.h> |
| |
| #include "efistub.h" |
| #include "x86-stub.h" |
| |
| extern char _bss[], _ebss[]; |
| |
| const efi_system_table_t *efi_system_table; |
| const efi_dxe_services_table_t *efi_dxe_table; |
| static efi_loaded_image_t *image = NULL; |
| static efi_memory_attribute_protocol_t *memattr; |
| |
| typedef union sev_memory_acceptance_protocol sev_memory_acceptance_protocol_t; |
| union sev_memory_acceptance_protocol { |
| struct { |
| efi_status_t (__efiapi * allow_unaccepted_memory)( |
| sev_memory_acceptance_protocol_t *); |
| }; |
| struct { |
| u32 allow_unaccepted_memory; |
| } mixed_mode; |
| }; |
| |
| static efi_status_t |
| preserve_pci_rom_image(efi_pci_io_protocol_t *pci, struct pci_setup_rom **__rom) |
| { |
| struct pci_setup_rom *rom = NULL; |
| efi_status_t status; |
| unsigned long size; |
| uint64_t romsize; |
| void *romimage; |
| |
| /* |
| * Some firmware images contain EFI function pointers at the place where |
| * the romimage and romsize fields are supposed to be. Typically the EFI |
| * code is mapped at high addresses, translating to an unrealistically |
| * large romsize. The UEFI spec limits the size of option ROMs to 16 |
| * MiB so we reject any ROMs over 16 MiB in size to catch this. |
| */ |
| romimage = efi_table_attr(pci, romimage); |
| romsize = efi_table_attr(pci, romsize); |
| if (!romimage || !romsize || romsize > SZ_16M) |
| return EFI_INVALID_PARAMETER; |
| |
| size = romsize + sizeof(*rom); |
| |
| status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, |
| (void **)&rom); |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to allocate memory for 'rom'\n"); |
| return status; |
| } |
| |
| memset(rom, 0, sizeof(*rom)); |
| |
| rom->data.type = SETUP_PCI; |
| rom->data.len = size - sizeof(struct setup_data); |
| rom->data.next = 0; |
| rom->pcilen = romsize; |
| *__rom = rom; |
| |
| status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16, |
| PCI_VENDOR_ID, 1, &rom->vendor); |
| |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to read rom->vendor\n"); |
| goto free_struct; |
| } |
| |
| status = efi_call_proto(pci, pci.read, EfiPciIoWidthUint16, |
| PCI_DEVICE_ID, 1, &rom->devid); |
| |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to read rom->devid\n"); |
| goto free_struct; |
| } |
| |
| status = efi_call_proto(pci, get_location, &rom->segment, &rom->bus, |
| &rom->device, &rom->function); |
| |
| if (status != EFI_SUCCESS) |
| goto free_struct; |
| |
| memcpy(rom->romdata, romimage, romsize); |
| return status; |
| |
| free_struct: |
| efi_bs_call(free_pool, rom); |
| return status; |
| } |
| |
| /* |
| * There's no way to return an informative status from this function, |
| * because any analysis (and printing of error messages) needs to be |
| * done directly at the EFI function call-site. |
| * |
| * For example, EFI_INVALID_PARAMETER could indicate a bug or maybe we |
| * just didn't find any PCI devices, but there's no way to tell outside |
| * the context of the call. |
| */ |
| static void setup_efi_pci(struct boot_params *params) |
| { |
| efi_status_t status; |
| void **pci_handle = NULL; |
| efi_guid_t pci_proto = EFI_PCI_IO_PROTOCOL_GUID; |
| unsigned long size = 0; |
| struct setup_data *data; |
| efi_handle_t h; |
| int i; |
| |
| status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, |
| &pci_proto, NULL, &size, pci_handle); |
| |
| if (status == EFI_BUFFER_TOO_SMALL) { |
| status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, |
| (void **)&pci_handle); |
| |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to allocate memory for 'pci_handle'\n"); |
| return; |
| } |
| |
| status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, |
| &pci_proto, NULL, &size, pci_handle); |
| } |
| |
| if (status != EFI_SUCCESS) |
| goto free_handle; |
| |
| data = (struct setup_data *)(unsigned long)params->hdr.setup_data; |
| |
| while (data && data->next) |
| data = (struct setup_data *)(unsigned long)data->next; |
| |
| for_each_efi_handle(h, pci_handle, size, i) { |
| efi_pci_io_protocol_t *pci = NULL; |
| struct pci_setup_rom *rom; |
| |
| status = efi_bs_call(handle_protocol, h, &pci_proto, |
| (void **)&pci); |
| if (status != EFI_SUCCESS || !pci) |
| continue; |
| |
| status = preserve_pci_rom_image(pci, &rom); |
| if (status != EFI_SUCCESS) |
| continue; |
| |
| if (data) |
| data->next = (unsigned long)rom; |
| else |
| params->hdr.setup_data = (unsigned long)rom; |
| |
| data = (struct setup_data *)rom; |
| } |
| |
| free_handle: |
| efi_bs_call(free_pool, pci_handle); |
| } |
| |
| static void retrieve_apple_device_properties(struct boot_params *boot_params) |
| { |
| efi_guid_t guid = APPLE_PROPERTIES_PROTOCOL_GUID; |
| struct setup_data *data, *new; |
| efi_status_t status; |
| u32 size = 0; |
| apple_properties_protocol_t *p; |
| |
| status = efi_bs_call(locate_protocol, &guid, NULL, (void **)&p); |
| if (status != EFI_SUCCESS) |
| return; |
| |
| if (efi_table_attr(p, version) != 0x10000) { |
| efi_err("Unsupported properties proto version\n"); |
| return; |
| } |
| |
| efi_call_proto(p, get_all, NULL, &size); |
| if (!size) |
| return; |
| |
| do { |
| status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, |
| size + sizeof(struct setup_data), |
| (void **)&new); |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to allocate memory for 'properties'\n"); |
| return; |
| } |
| |
| status = efi_call_proto(p, get_all, new->data, &size); |
| |
| if (status == EFI_BUFFER_TOO_SMALL) |
| efi_bs_call(free_pool, new); |
| } while (status == EFI_BUFFER_TOO_SMALL); |
| |
| new->type = SETUP_APPLE_PROPERTIES; |
| new->len = size; |
| new->next = 0; |
| |
| data = (struct setup_data *)(unsigned long)boot_params->hdr.setup_data; |
| if (!data) { |
| boot_params->hdr.setup_data = (unsigned long)new; |
| } else { |
| while (data->next) |
| data = (struct setup_data *)(unsigned long)data->next; |
| data->next = (unsigned long)new; |
| } |
| } |
| |
| efi_status_t efi_adjust_memory_range_protection(unsigned long start, |
| unsigned long size) |
| { |
| efi_status_t status; |
| efi_gcd_memory_space_desc_t desc; |
| unsigned long end, next; |
| unsigned long rounded_start, rounded_end; |
| unsigned long unprotect_start, unprotect_size; |
| |
| rounded_start = rounddown(start, EFI_PAGE_SIZE); |
| rounded_end = roundup(start + size, EFI_PAGE_SIZE); |
| |
| if (memattr != NULL) { |
| status = efi_call_proto(memattr, set_memory_attributes, |
| rounded_start, |
| rounded_end - rounded_start, |
| EFI_MEMORY_RO); |
| if (status != EFI_SUCCESS) { |
| efi_warn("Failed to set EFI_MEMORY_RO attribute\n"); |
| return status; |
| } |
| |
| status = efi_call_proto(memattr, clear_memory_attributes, |
| rounded_start, |
| rounded_end - rounded_start, |
| EFI_MEMORY_XP); |
| if (status != EFI_SUCCESS) |
| efi_warn("Failed to clear EFI_MEMORY_XP attribute\n"); |
| return status; |
| } |
| |
| if (efi_dxe_table == NULL) |
| return EFI_SUCCESS; |
| |
| /* |
| * Don't modify memory region attributes, they are |
| * already suitable, to lower the possibility to |
| * encounter firmware bugs. |
| */ |
| |
| for (end = start + size; start < end; start = next) { |
| |
| status = efi_dxe_call(get_memory_space_descriptor, start, &desc); |
| |
| if (status != EFI_SUCCESS) |
| break; |
| |
| next = desc.base_address + desc.length; |
| |
| /* |
| * Only system memory is suitable for trampoline/kernel image placement, |
| * so only this type of memory needs its attributes to be modified. |
| */ |
| |
| if (desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory || |
| (desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0) |
| continue; |
| |
| unprotect_start = max(rounded_start, (unsigned long)desc.base_address); |
| unprotect_size = min(rounded_end, next) - unprotect_start; |
| |
| status = efi_dxe_call(set_memory_space_attributes, |
| unprotect_start, unprotect_size, |
| EFI_MEMORY_WB); |
| |
| if (status != EFI_SUCCESS) { |
| efi_warn("Unable to unprotect memory range [%08lx,%08lx]: %lx\n", |
| unprotect_start, |
| unprotect_start + unprotect_size, |
| status); |
| break; |
| } |
| } |
| return EFI_SUCCESS; |
| } |
| |
| static void setup_unaccepted_memory(void) |
| { |
| efi_guid_t mem_acceptance_proto = OVMF_SEV_MEMORY_ACCEPTANCE_PROTOCOL_GUID; |
| sev_memory_acceptance_protocol_t *proto; |
| efi_status_t status; |
| |
| if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) |
| return; |
| |
| /* |
| * Enable unaccepted memory before calling exit boot services in order |
| * for the UEFI to not accept all memory on EBS. |
| */ |
| status = efi_bs_call(locate_protocol, &mem_acceptance_proto, NULL, |
| (void **)&proto); |
| if (status != EFI_SUCCESS) |
| return; |
| |
| status = efi_call_proto(proto, allow_unaccepted_memory); |
| if (status != EFI_SUCCESS) |
| efi_err("Memory acceptance protocol failed\n"); |
| } |
| |
| static efi_char16_t *efistub_fw_vendor(void) |
| { |
| unsigned long vendor = efi_table_attr(efi_system_table, fw_vendor); |
| |
| return (efi_char16_t *)vendor; |
| } |
| |
| static const efi_char16_t apple[] = L"Apple"; |
| |
| static void setup_quirks(struct boot_params *boot_params) |
| { |
| if (IS_ENABLED(CONFIG_APPLE_PROPERTIES) && |
| !memcmp(efistub_fw_vendor(), apple, sizeof(apple))) |
| retrieve_apple_device_properties(boot_params); |
| } |
| |
| /* |
| * See if we have Universal Graphics Adapter (UGA) protocol |
| */ |
| static efi_status_t |
| setup_uga(struct screen_info *si, efi_guid_t *uga_proto, unsigned long size) |
| { |
| efi_status_t status; |
| u32 width, height; |
| void **uga_handle = NULL; |
| efi_uga_draw_protocol_t *uga = NULL, *first_uga; |
| efi_handle_t handle; |
| int i; |
| |
| status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, |
| (void **)&uga_handle); |
| if (status != EFI_SUCCESS) |
| return status; |
| |
| status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, |
| uga_proto, NULL, &size, uga_handle); |
| if (status != EFI_SUCCESS) |
| goto free_handle; |
| |
| height = 0; |
| width = 0; |
| |
| first_uga = NULL; |
| for_each_efi_handle(handle, uga_handle, size, i) { |
| efi_guid_t pciio_proto = EFI_PCI_IO_PROTOCOL_GUID; |
| u32 w, h, depth, refresh; |
| void *pciio; |
| |
| status = efi_bs_call(handle_protocol, handle, uga_proto, |
| (void **)&uga); |
| if (status != EFI_SUCCESS) |
| continue; |
| |
| pciio = NULL; |
| efi_bs_call(handle_protocol, handle, &pciio_proto, &pciio); |
| |
| status = efi_call_proto(uga, get_mode, &w, &h, &depth, &refresh); |
| if (status == EFI_SUCCESS && (!first_uga || pciio)) { |
| width = w; |
| height = h; |
| |
| /* |
| * Once we've found a UGA supporting PCIIO, |
| * don't bother looking any further. |
| */ |
| if (pciio) |
| break; |
| |
| first_uga = uga; |
| } |
| } |
| |
| if (!width && !height) |
| goto free_handle; |
| |
| /* EFI framebuffer */ |
| si->orig_video_isVGA = VIDEO_TYPE_EFI; |
| |
| si->lfb_depth = 32; |
| si->lfb_width = width; |
| si->lfb_height = height; |
| |
| si->red_size = 8; |
| si->red_pos = 16; |
| si->green_size = 8; |
| si->green_pos = 8; |
| si->blue_size = 8; |
| si->blue_pos = 0; |
| si->rsvd_size = 8; |
| si->rsvd_pos = 24; |
| |
| free_handle: |
| efi_bs_call(free_pool, uga_handle); |
| |
| return status; |
| } |
| |
| static void setup_graphics(struct boot_params *boot_params) |
| { |
| efi_guid_t graphics_proto = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID; |
| struct screen_info *si; |
| efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID; |
| efi_status_t status; |
| unsigned long size; |
| void **gop_handle = NULL; |
| void **uga_handle = NULL; |
| |
| si = &boot_params->screen_info; |
| memset(si, 0, sizeof(*si)); |
| |
| size = 0; |
| status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, |
| &graphics_proto, NULL, &size, gop_handle); |
| if (status == EFI_BUFFER_TOO_SMALL) |
| status = efi_setup_gop(si, &graphics_proto, size); |
| |
| if (status != EFI_SUCCESS) { |
| size = 0; |
| status = efi_bs_call(locate_handle, EFI_LOCATE_BY_PROTOCOL, |
| &uga_proto, NULL, &size, uga_handle); |
| if (status == EFI_BUFFER_TOO_SMALL) |
| setup_uga(si, &uga_proto, size); |
| } |
| } |
| |
| |
| static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status) |
| { |
| efi_bs_call(exit, handle, status, 0, NULL); |
| for(;;) |
| asm("hlt"); |
| } |
| |
| void __noreturn efi_stub_entry(efi_handle_t handle, |
| efi_system_table_t *sys_table_arg, |
| struct boot_params *boot_params); |
| |
| /* |
| * Because the x86 boot code expects to be passed a boot_params we |
| * need to create one ourselves (usually the bootloader would create |
| * one for us). |
| */ |
| efi_status_t __efiapi efi_pe_entry(efi_handle_t handle, |
| efi_system_table_t *sys_table_arg) |
| { |
| static struct boot_params boot_params __page_aligned_bss; |
| struct setup_header *hdr = &boot_params.hdr; |
| efi_guid_t proto = LOADED_IMAGE_PROTOCOL_GUID; |
| int options_size = 0; |
| efi_status_t status; |
| char *cmdline_ptr; |
| |
| if (efi_is_native()) |
| memset(_bss, 0, _ebss - _bss); |
| |
| efi_system_table = sys_table_arg; |
| |
| /* Check if we were booted by the EFI firmware */ |
| if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) |
| efi_exit(handle, EFI_INVALID_PARAMETER); |
| |
| status = efi_bs_call(handle_protocol, handle, &proto, (void **)&image); |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to get handle for LOADED_IMAGE_PROTOCOL\n"); |
| efi_exit(handle, status); |
| } |
| |
| /* Assign the setup_header fields that the kernel actually cares about */ |
| hdr->root_flags = 1; |
| hdr->vid_mode = 0xffff; |
| |
| hdr->type_of_loader = 0x21; |
| |
| /* Convert unicode cmdline to ascii */ |
| cmdline_ptr = efi_convert_cmdline(image, &options_size); |
| if (!cmdline_ptr) |
| goto fail; |
| |
| efi_set_u64_split((unsigned long)cmdline_ptr, &hdr->cmd_line_ptr, |
| &boot_params.ext_cmd_line_ptr); |
| |
| efi_stub_entry(handle, sys_table_arg, &boot_params); |
| /* not reached */ |
| |
| fail: |
| efi_exit(handle, status); |
| } |
| |
| static void add_e820ext(struct boot_params *params, |
| struct setup_data *e820ext, u32 nr_entries) |
| { |
| struct setup_data *data; |
| |
| e820ext->type = SETUP_E820_EXT; |
| e820ext->len = nr_entries * sizeof(struct boot_e820_entry); |
| e820ext->next = 0; |
| |
| data = (struct setup_data *)(unsigned long)params->hdr.setup_data; |
| |
| while (data && data->next) |
| data = (struct setup_data *)(unsigned long)data->next; |
| |
| if (data) |
| data->next = (unsigned long)e820ext; |
| else |
| params->hdr.setup_data = (unsigned long)e820ext; |
| } |
| |
| static efi_status_t |
| setup_e820(struct boot_params *params, struct setup_data *e820ext, u32 e820ext_size) |
| { |
| struct boot_e820_entry *entry = params->e820_table; |
| struct efi_info *efi = ¶ms->efi_info; |
| struct boot_e820_entry *prev = NULL; |
| u32 nr_entries; |
| u32 nr_desc; |
| int i; |
| |
| nr_entries = 0; |
| nr_desc = efi->efi_memmap_size / efi->efi_memdesc_size; |
| |
| for (i = 0; i < nr_desc; i++) { |
| efi_memory_desc_t *d; |
| unsigned int e820_type = 0; |
| unsigned long m = efi->efi_memmap; |
| |
| #ifdef CONFIG_X86_64 |
| m |= (u64)efi->efi_memmap_hi << 32; |
| #endif |
| |
| d = efi_early_memdesc_ptr(m, efi->efi_memdesc_size, i); |
| switch (d->type) { |
| case EFI_RESERVED_TYPE: |
| case EFI_RUNTIME_SERVICES_CODE: |
| case EFI_RUNTIME_SERVICES_DATA: |
| case EFI_MEMORY_MAPPED_IO: |
| case EFI_MEMORY_MAPPED_IO_PORT_SPACE: |
| case EFI_PAL_CODE: |
| e820_type = E820_TYPE_RESERVED; |
| break; |
| |
| case EFI_UNUSABLE_MEMORY: |
| e820_type = E820_TYPE_UNUSABLE; |
| break; |
| |
| case EFI_ACPI_RECLAIM_MEMORY: |
| e820_type = E820_TYPE_ACPI; |
| break; |
| |
| case EFI_LOADER_CODE: |
| case EFI_LOADER_DATA: |
| case EFI_BOOT_SERVICES_CODE: |
| case EFI_BOOT_SERVICES_DATA: |
| case EFI_CONVENTIONAL_MEMORY: |
| if (efi_soft_reserve_enabled() && |
| (d->attribute & EFI_MEMORY_SP)) |
| e820_type = E820_TYPE_SOFT_RESERVED; |
| else |
| e820_type = E820_TYPE_RAM; |
| break; |
| |
| case EFI_ACPI_MEMORY_NVS: |
| e820_type = E820_TYPE_NVS; |
| break; |
| |
| case EFI_PERSISTENT_MEMORY: |
| e820_type = E820_TYPE_PMEM; |
| break; |
| |
| case EFI_UNACCEPTED_MEMORY: |
| if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY)) |
| continue; |
| e820_type = E820_TYPE_RAM; |
| process_unaccepted_memory(d->phys_addr, |
| d->phys_addr + PAGE_SIZE * d->num_pages); |
| break; |
| default: |
| continue; |
| } |
| |
| /* Merge adjacent mappings */ |
| if (prev && prev->type == e820_type && |
| (prev->addr + prev->size) == d->phys_addr) { |
| prev->size += d->num_pages << 12; |
| continue; |
| } |
| |
| if (nr_entries == ARRAY_SIZE(params->e820_table)) { |
| u32 need = (nr_desc - i) * sizeof(struct e820_entry) + |
| sizeof(struct setup_data); |
| |
| if (!e820ext || e820ext_size < need) |
| return EFI_BUFFER_TOO_SMALL; |
| |
| /* boot_params map full, switch to e820 extended */ |
| entry = (struct boot_e820_entry *)e820ext->data; |
| } |
| |
| entry->addr = d->phys_addr; |
| entry->size = d->num_pages << PAGE_SHIFT; |
| entry->type = e820_type; |
| prev = entry++; |
| nr_entries++; |
| } |
| |
| if (nr_entries > ARRAY_SIZE(params->e820_table)) { |
| u32 nr_e820ext = nr_entries - ARRAY_SIZE(params->e820_table); |
| |
| add_e820ext(params, e820ext, nr_e820ext); |
| nr_entries -= nr_e820ext; |
| } |
| |
| params->e820_entries = (u8)nr_entries; |
| |
| return EFI_SUCCESS; |
| } |
| |
| static efi_status_t alloc_e820ext(u32 nr_desc, struct setup_data **e820ext, |
| u32 *e820ext_size) |
| { |
| efi_status_t status; |
| unsigned long size; |
| |
| size = sizeof(struct setup_data) + |
| sizeof(struct e820_entry) * nr_desc; |
| |
| if (*e820ext) { |
| efi_bs_call(free_pool, *e820ext); |
| *e820ext = NULL; |
| *e820ext_size = 0; |
| } |
| |
| status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, size, |
| (void **)e820ext); |
| if (status == EFI_SUCCESS) |
| *e820ext_size = size; |
| |
| return status; |
| } |
| |
| static efi_status_t allocate_e820(struct boot_params *params, |
| struct setup_data **e820ext, |
| u32 *e820ext_size) |
| { |
| struct efi_boot_memmap *map; |
| efi_status_t status; |
| __u32 nr_desc; |
| |
| status = efi_get_memory_map(&map, false); |
| if (status != EFI_SUCCESS) |
| return status; |
| |
| nr_desc = map->map_size / map->desc_size; |
| if (nr_desc > ARRAY_SIZE(params->e820_table) - EFI_MMAP_NR_SLACK_SLOTS) { |
| u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table) + |
| EFI_MMAP_NR_SLACK_SLOTS; |
| |
| status = alloc_e820ext(nr_e820ext, e820ext, e820ext_size); |
| } |
| |
| if (IS_ENABLED(CONFIG_UNACCEPTED_MEMORY) && status == EFI_SUCCESS) |
| status = allocate_unaccepted_bitmap(nr_desc, map); |
| |
| efi_bs_call(free_pool, map); |
| return status; |
| } |
| |
| struct exit_boot_struct { |
| struct boot_params *boot_params; |
| struct efi_info *efi; |
| }; |
| |
| static efi_status_t exit_boot_func(struct efi_boot_memmap *map, |
| void *priv) |
| { |
| const char *signature; |
| struct exit_boot_struct *p = priv; |
| |
| signature = efi_is_64bit() ? EFI64_LOADER_SIGNATURE |
| : EFI32_LOADER_SIGNATURE; |
| memcpy(&p->efi->efi_loader_signature, signature, sizeof(__u32)); |
| |
| efi_set_u64_split((unsigned long)efi_system_table, |
| &p->efi->efi_systab, &p->efi->efi_systab_hi); |
| p->efi->efi_memdesc_size = map->desc_size; |
| p->efi->efi_memdesc_version = map->desc_ver; |
| efi_set_u64_split((unsigned long)map->map, |
| &p->efi->efi_memmap, &p->efi->efi_memmap_hi); |
| p->efi->efi_memmap_size = map->map_size; |
| |
| return EFI_SUCCESS; |
| } |
| |
| static efi_status_t exit_boot(struct boot_params *boot_params, void *handle) |
| { |
| struct setup_data *e820ext = NULL; |
| __u32 e820ext_size = 0; |
| efi_status_t status; |
| struct exit_boot_struct priv; |
| |
| priv.boot_params = boot_params; |
| priv.efi = &boot_params->efi_info; |
| |
| status = allocate_e820(boot_params, &e820ext, &e820ext_size); |
| if (status != EFI_SUCCESS) |
| return status; |
| |
| /* Might as well exit boot services now */ |
| status = efi_exit_boot_services(handle, &priv, exit_boot_func); |
| if (status != EFI_SUCCESS) |
| return status; |
| |
| /* Historic? */ |
| boot_params->alt_mem_k = 32 * 1024; |
| |
| status = setup_e820(boot_params, e820ext, e820ext_size); |
| if (status != EFI_SUCCESS) |
| return status; |
| |
| return EFI_SUCCESS; |
| } |
| |
| static bool have_unsupported_snp_features(void) |
| { |
| u64 unsupported; |
| |
| unsupported = snp_get_unsupported_features(sev_get_status()); |
| if (unsupported) { |
| efi_err("Unsupported SEV-SNP features detected: 0x%llx\n", |
| unsupported); |
| return true; |
| } |
| return false; |
| } |
| |
| static void efi_get_seed(void *seed, int size) |
| { |
| efi_get_random_bytes(size, seed); |
| |
| /* |
| * This only updates seed[0] when running on 32-bit, but in that case, |
| * seed[1] is not used anyway, as there is no virtual KASLR on 32-bit. |
| */ |
| *(unsigned long *)seed ^= kaslr_get_random_long("EFI"); |
| } |
| |
| static void error(char *str) |
| { |
| efi_warn("Decompression failed: %s\n", str); |
| } |
| |
| static efi_status_t efi_decompress_kernel(unsigned long *kernel_entry) |
| { |
| unsigned long virt_addr = LOAD_PHYSICAL_ADDR; |
| unsigned long addr, alloc_size, entry; |
| efi_status_t status; |
| u32 seed[2] = {}; |
| |
| /* determine the required size of the allocation */ |
| alloc_size = ALIGN(max_t(unsigned long, output_len, kernel_total_size), |
| MIN_KERNEL_ALIGN); |
| |
| if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && !efi_nokaslr) { |
| u64 range = KERNEL_IMAGE_SIZE - LOAD_PHYSICAL_ADDR - kernel_total_size; |
| static const efi_char16_t ami[] = L"American Megatrends"; |
| |
| efi_get_seed(seed, sizeof(seed)); |
| |
| virt_addr += (range * seed[1]) >> 32; |
| virt_addr &= ~(CONFIG_PHYSICAL_ALIGN - 1); |
| |
| /* |
| * Older Dell systems with AMI UEFI firmware v2.0 may hang |
| * while decompressing the kernel if physical address |
| * randomization is enabled. |
| * |
| * https://bugzilla.kernel.org/show_bug.cgi?id=218173 |
| */ |
| if (efi_system_table->hdr.revision <= EFI_2_00_SYSTEM_TABLE_REVISION && |
| !memcmp(efistub_fw_vendor(), ami, sizeof(ami))) { |
| efi_debug("AMI firmware v2.0 or older detected - disabling physical KASLR\n"); |
| seed[0] = 0; |
| } |
| |
| boot_params_ptr->hdr.loadflags |= KASLR_FLAG; |
| } |
| |
| status = efi_random_alloc(alloc_size, CONFIG_PHYSICAL_ALIGN, &addr, |
| seed[0], EFI_LOADER_CODE, |
| LOAD_PHYSICAL_ADDR, |
| EFI_X86_KERNEL_ALLOC_LIMIT); |
| if (status != EFI_SUCCESS) |
| return status; |
| |
| entry = decompress_kernel((void *)addr, virt_addr, error); |
| if (entry == ULONG_MAX) { |
| efi_free(alloc_size, addr); |
| return EFI_LOAD_ERROR; |
| } |
| |
| *kernel_entry = addr + entry; |
| |
| return efi_adjust_memory_range_protection(addr, kernel_text_size); |
| } |
| |
| static void __noreturn enter_kernel(unsigned long kernel_addr, |
| struct boot_params *boot_params) |
| { |
| /* enter decompressed kernel with boot_params pointer in RSI/ESI */ |
| asm("jmp *%0"::"r"(kernel_addr), "S"(boot_params)); |
| |
| unreachable(); |
| } |
| |
| /* |
| * On success, this routine will jump to the relocated image directly and never |
| * return. On failure, it will exit to the firmware via efi_exit() instead of |
| * returning. |
| */ |
| void __noreturn efi_stub_entry(efi_handle_t handle, |
| efi_system_table_t *sys_table_arg, |
| struct boot_params *boot_params) |
| { |
| efi_guid_t guid = EFI_MEMORY_ATTRIBUTE_PROTOCOL_GUID; |
| struct setup_header *hdr = &boot_params->hdr; |
| const struct linux_efi_initrd *initrd = NULL; |
| unsigned long kernel_entry; |
| efi_status_t status; |
| |
| boot_params_ptr = boot_params; |
| |
| efi_system_table = sys_table_arg; |
| /* Check if we were booted by the EFI firmware */ |
| if (efi_system_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) |
| efi_exit(handle, EFI_INVALID_PARAMETER); |
| |
| if (have_unsupported_snp_features()) |
| efi_exit(handle, EFI_UNSUPPORTED); |
| |
| if (IS_ENABLED(CONFIG_EFI_DXE_MEM_ATTRIBUTES)) { |
| efi_dxe_table = get_efi_config_table(EFI_DXE_SERVICES_TABLE_GUID); |
| if (efi_dxe_table && |
| efi_dxe_table->hdr.signature != EFI_DXE_SERVICES_TABLE_SIGNATURE) { |
| efi_warn("Ignoring DXE services table: invalid signature\n"); |
| efi_dxe_table = NULL; |
| } |
| } |
| |
| /* grab the memory attributes protocol if it exists */ |
| efi_bs_call(locate_protocol, &guid, NULL, (void **)&memattr); |
| |
| status = efi_setup_5level_paging(); |
| if (status != EFI_SUCCESS) { |
| efi_err("efi_setup_5level_paging() failed!\n"); |
| goto fail; |
| } |
| |
| #ifdef CONFIG_CMDLINE_BOOL |
| status = efi_parse_options(CONFIG_CMDLINE); |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to parse options\n"); |
| goto fail; |
| } |
| #endif |
| if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) { |
| unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr | |
| ((u64)boot_params->ext_cmd_line_ptr << 32)); |
| status = efi_parse_options((char *)cmdline_paddr); |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to parse options\n"); |
| goto fail; |
| } |
| } |
| |
| status = efi_decompress_kernel(&kernel_entry); |
| if (status != EFI_SUCCESS) { |
| efi_err("Failed to decompress kernel\n"); |
| goto fail; |
| } |
| |
| /* |
| * At this point, an initrd may already have been loaded by the |
| * bootloader and passed via bootparams. We permit an initrd loaded |
| * from the LINUX_EFI_INITRD_MEDIA_GUID device path to supersede it. |
| * |
| * If the device path is not present, any command-line initrd= |
| * arguments will be processed only if image is not NULL, which will be |
| * the case only if we were loaded via the PE entry point. |
| */ |
| status = efi_load_initrd(image, hdr->initrd_addr_max, ULONG_MAX, |
| &initrd); |
| if (status != EFI_SUCCESS) |
| goto fail; |
| if (initrd && initrd->size > 0) { |
| efi_set_u64_split(initrd->base, &hdr->ramdisk_image, |
| &boot_params->ext_ramdisk_image); |
| efi_set_u64_split(initrd->size, &hdr->ramdisk_size, |
| &boot_params->ext_ramdisk_size); |
| } |
| |
| |
| /* |
| * If the boot loader gave us a value for secure_boot then we use that, |
| * otherwise we ask the BIOS. |
| */ |
| if (boot_params->secure_boot == efi_secureboot_mode_unset) |
| boot_params->secure_boot = efi_get_secureboot(); |
| |
| /* Ask the firmware to clear memory on unclean shutdown */ |
| efi_enable_reset_attack_mitigation(); |
| |
| efi_random_get_seed(); |
| |
| efi_retrieve_eventlog(); |
| |
| setup_graphics(boot_params); |
| |
| setup_efi_pci(boot_params); |
| |
| setup_quirks(boot_params); |
| |
| setup_unaccepted_memory(); |
| |
| status = exit_boot(boot_params, handle); |
| if (status != EFI_SUCCESS) { |
| efi_err("exit_boot() failed!\n"); |
| goto fail; |
| } |
| |
| /* |
| * Call the SEV init code while still running with the firmware's |
| * GDT/IDT, so #VC exceptions will be handled by EFI. |
| */ |
| sev_enable(boot_params); |
| |
| efi_5level_switch(); |
| |
| enter_kernel(kernel_entry, boot_params); |
| fail: |
| efi_err("efi_stub_entry() failed!\n"); |
| |
| efi_exit(handle, status); |
| } |
| |
| #ifdef CONFIG_EFI_HANDOVER_PROTOCOL |
| void efi_handover_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg, |
| struct boot_params *boot_params) |
| { |
| memset(_bss, 0, _ebss - _bss); |
| efi_stub_entry(handle, sys_table_arg, boot_params); |
| } |
| |
| #ifndef CONFIG_EFI_MIXED |
| extern __alias(efi_handover_entry) |
| void efi32_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg, |
| struct boot_params *boot_params); |
| |
| extern __alias(efi_handover_entry) |
| void efi64_stub_entry(efi_handle_t handle, efi_system_table_t *sys_table_arg, |
| struct boot_params *boot_params); |
| #endif |
| #endif |