2 * efi.c - EFI subsystem
4 * Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
5 * Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
6 * Copyright (C) 2013 Tom Gundersen <teg@jklm.no>
8 * This code registers /sys/firmware/efi{,/efivars} when EFI is supported,
9 * allowing the efivarfs to be mounted or the efivars module to be loaded.
10 * The existance of /sys/firmware/efi may also be used by userspace to
11 * determine that the system supports EFI.
13 * This file is released under the GPLv2.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/kobject.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/device.h>
22 #include <linux/efi.h>
24 #include <linux/of_fdt.h>
26 #include <linux/kexec.h>
27 #include <linux/platform_device.h>
28 #include <linux/random.h>
29 #include <linux/reboot.h>
30 #include <linux/slab.h>
31 #include <linux/acpi.h>
32 #include <linux/ucs2_string.h>
33 #include <linux/memblock.h>
35 #include <asm/early_ioremap.h>
37 struct efi __read_mostly efi = {
38 .mps = EFI_INVALID_TABLE_ADDR,
39 .acpi = EFI_INVALID_TABLE_ADDR,
40 .acpi20 = EFI_INVALID_TABLE_ADDR,
41 .smbios = EFI_INVALID_TABLE_ADDR,
42 .smbios3 = EFI_INVALID_TABLE_ADDR,
43 .sal_systab = EFI_INVALID_TABLE_ADDR,
44 .boot_info = EFI_INVALID_TABLE_ADDR,
45 .hcdp = EFI_INVALID_TABLE_ADDR,
46 .uga = EFI_INVALID_TABLE_ADDR,
47 .uv_systab = EFI_INVALID_TABLE_ADDR,
48 .fw_vendor = EFI_INVALID_TABLE_ADDR,
49 .runtime = EFI_INVALID_TABLE_ADDR,
50 .config_table = EFI_INVALID_TABLE_ADDR,
51 .esrt = EFI_INVALID_TABLE_ADDR,
52 .properties_table = EFI_INVALID_TABLE_ADDR,
53 .mem_attr_table = EFI_INVALID_TABLE_ADDR,
54 .rng_seed = EFI_INVALID_TABLE_ADDR,
58 static unsigned long *efi_tables[] = {
73 &efi.properties_table,
77 static bool disable_runtime;
78 static int __init setup_noefi(char *arg)
80 disable_runtime = true;
83 early_param("noefi", setup_noefi);
85 bool efi_runtime_disabled(void)
87 return disable_runtime;
90 static int __init parse_efi_cmdline(char *str)
93 pr_warn("need at least one option\n");
97 if (parse_option_str(str, "debug"))
98 set_bit(EFI_DBG, &efi.flags);
100 if (parse_option_str(str, "noruntime"))
101 disable_runtime = true;
105 early_param("efi", parse_efi_cmdline);
107 struct kobject *efi_kobj;
110 * Let's not leave out systab information that snuck into
112 * Note, do not add more fields in systab sysfs file as it breaks sysfs
113 * one value per file rule!
115 static ssize_t systab_show(struct kobject *kobj,
116 struct kobj_attribute *attr, char *buf)
123 if (efi.mps != EFI_INVALID_TABLE_ADDR)
124 str += sprintf(str, "MPS=0x%lx\n", efi.mps);
125 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
126 str += sprintf(str, "ACPI20=0x%lx\n", efi.acpi20);
127 if (efi.acpi != EFI_INVALID_TABLE_ADDR)
128 str += sprintf(str, "ACPI=0x%lx\n", efi.acpi);
130 * If both SMBIOS and SMBIOS3 entry points are implemented, the
131 * SMBIOS3 entry point shall be preferred, so we list it first to
132 * let applications stop parsing after the first match.
134 if (efi.smbios3 != EFI_INVALID_TABLE_ADDR)
135 str += sprintf(str, "SMBIOS3=0x%lx\n", efi.smbios3);
136 if (efi.smbios != EFI_INVALID_TABLE_ADDR)
137 str += sprintf(str, "SMBIOS=0x%lx\n", efi.smbios);
138 if (efi.hcdp != EFI_INVALID_TABLE_ADDR)
139 str += sprintf(str, "HCDP=0x%lx\n", efi.hcdp);
140 if (efi.boot_info != EFI_INVALID_TABLE_ADDR)
141 str += sprintf(str, "BOOTINFO=0x%lx\n", efi.boot_info);
142 if (efi.uga != EFI_INVALID_TABLE_ADDR)
143 str += sprintf(str, "UGA=0x%lx\n", efi.uga);
148 static struct kobj_attribute efi_attr_systab = __ATTR_RO_MODE(systab, 0400);
150 #define EFI_FIELD(var) efi.var
152 #define EFI_ATTR_SHOW(name) \
153 static ssize_t name##_show(struct kobject *kobj, \
154 struct kobj_attribute *attr, char *buf) \
156 return sprintf(buf, "0x%lx\n", EFI_FIELD(name)); \
159 EFI_ATTR_SHOW(fw_vendor);
160 EFI_ATTR_SHOW(runtime);
161 EFI_ATTR_SHOW(config_table);
163 static ssize_t fw_platform_size_show(struct kobject *kobj,
164 struct kobj_attribute *attr, char *buf)
166 return sprintf(buf, "%d\n", efi_enabled(EFI_64BIT) ? 64 : 32);
169 static struct kobj_attribute efi_attr_fw_vendor = __ATTR_RO(fw_vendor);
170 static struct kobj_attribute efi_attr_runtime = __ATTR_RO(runtime);
171 static struct kobj_attribute efi_attr_config_table = __ATTR_RO(config_table);
172 static struct kobj_attribute efi_attr_fw_platform_size =
173 __ATTR_RO(fw_platform_size);
175 static struct attribute *efi_subsys_attrs[] = {
176 &efi_attr_systab.attr,
177 &efi_attr_fw_vendor.attr,
178 &efi_attr_runtime.attr,
179 &efi_attr_config_table.attr,
180 &efi_attr_fw_platform_size.attr,
184 static umode_t efi_attr_is_visible(struct kobject *kobj,
185 struct attribute *attr, int n)
187 if (attr == &efi_attr_fw_vendor.attr) {
188 if (efi_enabled(EFI_PARAVIRT) ||
189 efi.fw_vendor == EFI_INVALID_TABLE_ADDR)
191 } else if (attr == &efi_attr_runtime.attr) {
192 if (efi.runtime == EFI_INVALID_TABLE_ADDR)
194 } else if (attr == &efi_attr_config_table.attr) {
195 if (efi.config_table == EFI_INVALID_TABLE_ADDR)
202 static const struct attribute_group efi_subsys_attr_group = {
203 .attrs = efi_subsys_attrs,
204 .is_visible = efi_attr_is_visible,
207 static struct efivars generic_efivars;
208 static struct efivar_operations generic_ops;
210 static int generic_ops_register(void)
212 generic_ops.get_variable = efi.get_variable;
213 generic_ops.set_variable = efi.set_variable;
214 generic_ops.set_variable_nonblocking = efi.set_variable_nonblocking;
215 generic_ops.get_next_variable = efi.get_next_variable;
216 generic_ops.query_variable_store = efi_query_variable_store;
218 return efivars_register(&generic_efivars, &generic_ops, efi_kobj);
221 static void generic_ops_unregister(void)
223 efivars_unregister(&generic_efivars);
226 #if IS_ENABLED(CONFIG_ACPI)
227 #define EFIVAR_SSDT_NAME_MAX 16
228 static char efivar_ssdt[EFIVAR_SSDT_NAME_MAX] __initdata;
229 static int __init efivar_ssdt_setup(char *str)
231 if (strlen(str) < sizeof(efivar_ssdt))
232 memcpy(efivar_ssdt, str, strlen(str));
234 pr_warn("efivar_ssdt: name too long: %s\n", str);
237 __setup("efivar_ssdt=", efivar_ssdt_setup);
239 static __init int efivar_ssdt_iter(efi_char16_t *name, efi_guid_t vendor,
240 unsigned long name_size, void *data)
242 struct efivar_entry *entry;
243 struct list_head *list = data;
244 char utf8_name[EFIVAR_SSDT_NAME_MAX];
245 int limit = min_t(unsigned long, EFIVAR_SSDT_NAME_MAX, name_size);
247 ucs2_as_utf8(utf8_name, name, limit - 1);
248 if (strncmp(utf8_name, efivar_ssdt, limit) != 0)
251 entry = kmalloc(sizeof(*entry), GFP_KERNEL);
255 memcpy(entry->var.VariableName, name, name_size);
256 memcpy(&entry->var.VendorGuid, &vendor, sizeof(efi_guid_t));
258 efivar_entry_add(entry, list);
263 static __init int efivar_ssdt_load(void)
266 struct efivar_entry *entry, *aux;
271 ret = efivar_init(efivar_ssdt_iter, &entries, true, &entries);
273 list_for_each_entry_safe(entry, aux, &entries, list) {
274 pr_info("loading SSDT from variable %s-%pUl\n", efivar_ssdt,
275 &entry->var.VendorGuid);
277 list_del(&entry->list);
279 ret = efivar_entry_size(entry, &size);
281 pr_err("failed to get var size\n");
285 data = kmalloc(size, GFP_KERNEL);
291 ret = efivar_entry_get(entry, NULL, &size, data);
293 pr_err("failed to get var data\n");
297 ret = acpi_load_table(data);
299 pr_err("failed to load table: %d\n", ret);
315 static inline int efivar_ssdt_load(void) { return 0; }
319 * We register the efi subsystem with the firmware subsystem and the
320 * efivars subsystem with the efi subsystem, if the system was booted with
323 static int __init efisubsys_init(void)
327 if (!efi_enabled(EFI_BOOT))
330 /* We register the efi directory at /sys/firmware/efi */
331 efi_kobj = kobject_create_and_add("efi", firmware_kobj);
333 pr_err("efi: Firmware registration failed.\n");
337 error = generic_ops_register();
341 if (efi_enabled(EFI_RUNTIME_SERVICES))
344 error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group);
346 pr_err("efi: Sysfs attribute export failed with error %d.\n",
351 error = efi_runtime_map_init(efi_kobj);
353 goto err_remove_group;
355 /* and the standard mountpoint for efivarfs */
356 error = sysfs_create_mount_point(efi_kobj, "efivars");
358 pr_err("efivars: Subsystem registration failed.\n");
359 goto err_remove_group;
365 sysfs_remove_group(efi_kobj, &efi_subsys_attr_group);
367 generic_ops_unregister();
369 kobject_put(efi_kobj);
373 subsys_initcall(efisubsys_init);
376 * Find the efi memory descriptor for a given physical address. Given a
377 * physical address, determine if it exists within an EFI Memory Map entry,
378 * and if so, populate the supplied memory descriptor with the appropriate
381 int __init efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
383 efi_memory_desc_t *md;
385 if (!efi_enabled(EFI_MEMMAP)) {
386 pr_err_once("EFI_MEMMAP is not enabled.\n");
391 pr_err_once("out_md is null.\n");
395 for_each_efi_memory_desc(md) {
399 if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
400 md->type != EFI_BOOT_SERVICES_DATA &&
401 md->type != EFI_RUNTIME_SERVICES_DATA) {
405 size = md->num_pages << EFI_PAGE_SHIFT;
406 end = md->phys_addr + size;
407 if (phys_addr >= md->phys_addr && phys_addr < end) {
408 memcpy(out_md, md, sizeof(*out_md));
416 * Calculate the highest address of an efi memory descriptor.
418 u64 __init efi_mem_desc_end(efi_memory_desc_t *md)
420 u64 size = md->num_pages << EFI_PAGE_SHIFT;
421 u64 end = md->phys_addr + size;
425 void __init __weak efi_arch_mem_reserve(phys_addr_t addr, u64 size) {}
428 * efi_mem_reserve - Reserve an EFI memory region
429 * @addr: Physical address to reserve
430 * @size: Size of reservation
432 * Mark a region as reserved from general kernel allocation and
433 * prevent it being released by efi_free_boot_services().
435 * This function should be called drivers once they've parsed EFI
436 * configuration tables to figure out where their data lives, e.g.
439 void __init efi_mem_reserve(phys_addr_t addr, u64 size)
441 if (!memblock_is_region_reserved(addr, size))
442 memblock_reserve(addr, size);
445 * Some architectures (x86) reserve all boot services ranges
446 * until efi_free_boot_services() because of buggy firmware
447 * implementations. This means the above memblock_reserve() is
448 * superfluous on x86 and instead what it needs to do is
449 * ensure the @start, @size is not freed.
451 efi_arch_mem_reserve(addr, size);
454 static __initdata efi_config_table_type_t common_tables[] = {
455 {ACPI_20_TABLE_GUID, "ACPI 2.0", &efi.acpi20},
456 {ACPI_TABLE_GUID, "ACPI", &efi.acpi},
457 {HCDP_TABLE_GUID, "HCDP", &efi.hcdp},
458 {MPS_TABLE_GUID, "MPS", &efi.mps},
459 {SAL_SYSTEM_TABLE_GUID, "SALsystab", &efi.sal_systab},
460 {SMBIOS_TABLE_GUID, "SMBIOS", &efi.smbios},
461 {SMBIOS3_TABLE_GUID, "SMBIOS 3.0", &efi.smbios3},
462 {UGA_IO_PROTOCOL_GUID, "UGA", &efi.uga},
463 {EFI_SYSTEM_RESOURCE_TABLE_GUID, "ESRT", &efi.esrt},
464 {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table},
465 {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table},
466 {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed},
467 {NULL_GUID, NULL, NULL},
470 static __init int match_config_table(efi_guid_t *guid,
472 efi_config_table_type_t *table_types)
477 for (i = 0; efi_guidcmp(table_types[i].guid, NULL_GUID); i++) {
478 if (!efi_guidcmp(*guid, table_types[i].guid)) {
479 *(table_types[i].ptr) = table;
480 if (table_types[i].name)
481 pr_cont(" %s=0x%lx ",
482 table_types[i].name, table);
491 int __init efi_config_parse_tables(void *config_tables, int count, int sz,
492 efi_config_table_type_t *arch_tables)
497 tablep = config_tables;
499 for (i = 0; i < count; i++) {
503 if (efi_enabled(EFI_64BIT)) {
505 guid = ((efi_config_table_64_t *)tablep)->guid;
506 table64 = ((efi_config_table_64_t *)tablep)->table;
511 pr_err("Table located above 4GB, disabling EFI.\n");
516 guid = ((efi_config_table_32_t *)tablep)->guid;
517 table = ((efi_config_table_32_t *)tablep)->table;
520 if (!match_config_table(&guid, table, common_tables))
521 match_config_table(&guid, table, arch_tables);
526 set_bit(EFI_CONFIG_TABLES, &efi.flags);
528 if (efi.rng_seed != EFI_INVALID_TABLE_ADDR) {
529 struct linux_efi_random_seed *seed;
532 seed = early_memremap(efi.rng_seed, sizeof(*seed));
535 early_memunmap(seed, sizeof(*seed));
537 pr_err("Could not map UEFI random seed!\n");
540 seed = early_memremap(efi.rng_seed,
541 sizeof(*seed) + size);
543 add_device_randomness(seed->bits, seed->size);
544 early_memunmap(seed, sizeof(*seed) + size);
545 pr_notice("seeding entropy pool\n");
547 pr_err("Could not map UEFI random seed!\n");
552 if (efi_enabled(EFI_MEMMAP))
555 /* Parse the EFI Properties table if it exists */
556 if (efi.properties_table != EFI_INVALID_TABLE_ADDR) {
557 efi_properties_table_t *tbl;
559 tbl = early_memremap(efi.properties_table, sizeof(*tbl));
561 pr_err("Could not map Properties table!\n");
565 if (tbl->memory_protection_attribute &
566 EFI_PROPERTIES_RUNTIME_MEMORY_PROTECTION_NON_EXECUTABLE_PE_DATA)
567 set_bit(EFI_NX_PE_DATA, &efi.flags);
569 early_memunmap(tbl, sizeof(*tbl));
575 int __init efi_config_init(efi_config_table_type_t *arch_tables)
580 if (efi_enabled(EFI_64BIT))
581 sz = sizeof(efi_config_table_64_t);
583 sz = sizeof(efi_config_table_32_t);
586 * Let's see what config tables the firmware passed to us.
588 config_tables = early_memremap(efi.systab->tables,
589 efi.systab->nr_tables * sz);
590 if (config_tables == NULL) {
591 pr_err("Could not map Configuration table!\n");
595 ret = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sz,
598 early_memunmap(config_tables, efi.systab->nr_tables * sz);
602 #ifdef CONFIG_EFI_VARS_MODULE
603 static int __init efi_load_efivars(void)
605 struct platform_device *pdev;
607 if (!efi_enabled(EFI_RUNTIME_SERVICES))
610 pdev = platform_device_register_simple("efivars", 0, NULL, 0);
611 return IS_ERR(pdev) ? PTR_ERR(pdev) : 0;
613 device_initcall(efi_load_efivars);
616 #ifdef CONFIG_EFI_PARAMS_FROM_FDT
618 #define UEFI_PARAM(name, prop, field) \
622 offsetof(struct efi_fdt_params, field), \
623 FIELD_SIZEOF(struct efi_fdt_params, field) \
628 const char propname[32];
633 static __initdata struct params fdt_params[] = {
634 UEFI_PARAM("System Table", "linux,uefi-system-table", system_table),
635 UEFI_PARAM("MemMap Address", "linux,uefi-mmap-start", mmap),
636 UEFI_PARAM("MemMap Size", "linux,uefi-mmap-size", mmap_size),
637 UEFI_PARAM("MemMap Desc. Size", "linux,uefi-mmap-desc-size", desc_size),
638 UEFI_PARAM("MemMap Desc. Version", "linux,uefi-mmap-desc-ver", desc_ver)
641 static __initdata struct params xen_fdt_params[] = {
642 UEFI_PARAM("System Table", "xen,uefi-system-table", system_table),
643 UEFI_PARAM("MemMap Address", "xen,uefi-mmap-start", mmap),
644 UEFI_PARAM("MemMap Size", "xen,uefi-mmap-size", mmap_size),
645 UEFI_PARAM("MemMap Desc. Size", "xen,uefi-mmap-desc-size", desc_size),
646 UEFI_PARAM("MemMap Desc. Version", "xen,uefi-mmap-desc-ver", desc_ver)
649 #define EFI_FDT_PARAMS_SIZE ARRAY_SIZE(fdt_params)
651 static __initdata struct {
654 struct params *params;
656 { "hypervisor", "uefi", xen_fdt_params },
657 { "chosen", NULL, fdt_params },
666 static int __init __find_uefi_params(unsigned long node,
667 struct param_info *info,
668 struct params *params)
675 for (i = 0; i < EFI_FDT_PARAMS_SIZE; i++) {
676 prop = of_get_flat_dt_prop(node, params[i].propname, &len);
678 info->missing = params[i].name;
682 dest = info->params + params[i].offset;
685 val = of_read_number(prop, len / sizeof(u32));
687 if (params[i].size == sizeof(u32))
692 if (efi_enabled(EFI_DBG))
693 pr_info(" %s: 0x%0*llx\n", params[i].name,
694 params[i].size * 2, val);
700 static int __init fdt_find_uefi_params(unsigned long node, const char *uname,
701 int depth, void *data)
703 struct param_info *info = data;
706 for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
707 const char *subnode = dt_params[i].subnode;
709 if (depth != 1 || strcmp(uname, dt_params[i].uname) != 0) {
710 info->missing = dt_params[i].params[0].name;
715 int err = of_get_flat_dt_subnode_by_name(node, subnode);
723 return __find_uefi_params(node, info, dt_params[i].params);
729 int __init efi_get_fdt_params(struct efi_fdt_params *params)
731 struct param_info info;
734 pr_info("Getting EFI parameters from FDT:\n");
737 info.params = params;
739 ret = of_scan_flat_dt(fdt_find_uefi_params, &info);
741 pr_info("UEFI not found.\n");
743 pr_err("Can't find '%s' in device tree!\n",
748 #endif /* CONFIG_EFI_PARAMS_FROM_FDT */
750 static __initdata char memory_type_name[][20] = {
758 "Conventional Memory",
760 "ACPI Reclaim Memory",
768 char * __init efi_md_typeattr_format(char *buf, size_t size,
769 const efi_memory_desc_t *md)
776 if (md->type >= ARRAY_SIZE(memory_type_name))
777 type_len = snprintf(pos, size, "[type=%u", md->type);
779 type_len = snprintf(pos, size, "[%-*s",
780 (int)(sizeof(memory_type_name[0]) - 1),
781 memory_type_name[md->type]);
782 if (type_len >= size)
788 attr = md->attribute;
789 if (attr & ~(EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_WT |
790 EFI_MEMORY_WB | EFI_MEMORY_UCE | EFI_MEMORY_RO |
791 EFI_MEMORY_WP | EFI_MEMORY_RP | EFI_MEMORY_XP |
793 EFI_MEMORY_RUNTIME | EFI_MEMORY_MORE_RELIABLE))
794 snprintf(pos, size, "|attr=0x%016llx]",
795 (unsigned long long)attr);
798 "|%3s|%2s|%2s|%2s|%2s|%2s|%2s|%3s|%2s|%2s|%2s|%2s]",
799 attr & EFI_MEMORY_RUNTIME ? "RUN" : "",
800 attr & EFI_MEMORY_MORE_RELIABLE ? "MR" : "",
801 attr & EFI_MEMORY_NV ? "NV" : "",
802 attr & EFI_MEMORY_XP ? "XP" : "",
803 attr & EFI_MEMORY_RP ? "RP" : "",
804 attr & EFI_MEMORY_WP ? "WP" : "",
805 attr & EFI_MEMORY_RO ? "RO" : "",
806 attr & EFI_MEMORY_UCE ? "UCE" : "",
807 attr & EFI_MEMORY_WB ? "WB" : "",
808 attr & EFI_MEMORY_WT ? "WT" : "",
809 attr & EFI_MEMORY_WC ? "WC" : "",
810 attr & EFI_MEMORY_UC ? "UC" : "");
815 * IA64 has a funky EFI memory map that doesn't work the same way as
816 * other architectures.
820 * efi_mem_attributes - lookup memmap attributes for physical address
821 * @phys_addr: the physical address to lookup
823 * Search in the EFI memory map for the region covering
824 * @phys_addr. Returns the EFI memory attributes if the region
825 * was found in the memory map, 0 otherwise.
827 u64 efi_mem_attributes(unsigned long phys_addr)
829 efi_memory_desc_t *md;
831 if (!efi_enabled(EFI_MEMMAP))
834 for_each_efi_memory_desc(md) {
835 if ((md->phys_addr <= phys_addr) &&
836 (phys_addr < (md->phys_addr +
837 (md->num_pages << EFI_PAGE_SHIFT))))
838 return md->attribute;
844 * efi_mem_type - lookup memmap type for physical address
845 * @phys_addr: the physical address to lookup
847 * Search in the EFI memory map for the region covering @phys_addr.
848 * Returns the EFI memory type if the region was found in the memory
849 * map, EFI_RESERVED_TYPE (zero) otherwise.
851 int efi_mem_type(unsigned long phys_addr)
853 const efi_memory_desc_t *md;
855 if (!efi_enabled(EFI_MEMMAP))
858 for_each_efi_memory_desc(md) {
859 if ((md->phys_addr <= phys_addr) &&
860 (phys_addr < (md->phys_addr +
861 (md->num_pages << EFI_PAGE_SHIFT))))
868 int efi_status_to_err(efi_status_t status)
876 case EFI_INVALID_PARAMETER:
879 case EFI_OUT_OF_RESOURCES:
882 case EFI_DEVICE_ERROR:
885 case EFI_WRITE_PROTECTED:
888 case EFI_SECURITY_VIOLATION:
904 bool efi_is_table_address(unsigned long phys_addr)
908 if (phys_addr == EFI_INVALID_TABLE_ADDR)
911 for (i = 0; i < ARRAY_SIZE(efi_tables); i++)
912 if (*(efi_tables[i]) == phys_addr)
919 static int update_efi_random_seed(struct notifier_block *nb,
920 unsigned long code, void *unused)
922 struct linux_efi_random_seed *seed;
925 if (!kexec_in_progress)
928 seed = memremap(efi.rng_seed, sizeof(*seed), MEMREMAP_WB);
930 size = min(seed->size, EFI_RANDOM_SEED_SIZE);
933 pr_err("Could not map UEFI random seed!\n");
936 seed = memremap(efi.rng_seed, sizeof(*seed) + size,
940 get_random_bytes(seed->bits, seed->size);
943 pr_err("Could not map UEFI random seed!\n");
949 static struct notifier_block efi_random_seed_nb = {
950 .notifier_call = update_efi_random_seed,
953 static int register_update_efi_random_seed(void)
955 if (efi.rng_seed == EFI_INVALID_TABLE_ADDR)
957 return register_reboot_notifier(&efi_random_seed_nb);
959 late_initcall(register_update_efi_random_seed);