blob: d5a8182cf2e1cc7f5a90f68e2967c8ef6d1550ff [file] [log] [blame]
// 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;
hdr->initrd_addr_max = INT_MAX;
/* 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 = &params->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;
}
}
if (efi_mem_encrypt > 0)
hdr->xloadflags |= XLF_MEM_ENCRYPTION;
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