#define pr_fmt(fmt) "efi: " fmt
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|
#include <linux/init.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/time.h>
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#include <linux/types.h>
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#include <linux/efi.h>
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#include <linux/slab.h>
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#include <linux/memblock.h>
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#include <linux/bootmem.h>
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#include <linux/acpi.h>
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#include <linux/dmi.h>
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#include <asm/e820/api.h>
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#include <asm/efi.h>
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#include <asm/uv/uv.h>
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#include <asm/cpu_device_id.h>
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#define EFI_MIN_RESERVE 5120
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|
#define EFI_DUMMY_GUID \
|
EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)
|
|
#define QUARK_CSH_SIGNATURE 0x5f435348 /* _CSH */
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#define QUARK_SECURITY_HEADER_SIZE 0x400
|
|
/*
|
* Header prepended to the standard EFI capsule on Quark systems the are based
|
* on Intel firmware BSP.
|
* @csh_signature: Unique identifier to sanity check signed module
|
* presence ("_CSH").
|
* @version: Current version of CSH used. Should be one for Quark A0.
|
* @modulesize: Size of the entire module including the module header
|
* and payload.
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* @security_version_number_index: Index of SVN to use for validation of signed
|
* module.
|
* @security_version_number: Used to prevent against roll back of modules.
|
* @rsvd_module_id: Currently unused for Clanton (Quark).
|
* @rsvd_module_vendor: Vendor Identifier. For Intel products value is
|
* 0x00008086.
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* @rsvd_date: BCD representation of build date as yyyymmdd, where
|
* yyyy=4 digit year, mm=1-12, dd=1-31.
|
* @headersize: Total length of the header including including any
|
* padding optionally added by the signing tool.
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* @hash_algo: What Hash is used in the module signing.
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* @cryp_algo: What Crypto is used in the module signing.
|
* @keysize: Total length of the key data including including any
|
* padding optionally added by the signing tool.
|
* @signaturesize: Total length of the signature including including any
|
* padding optionally added by the signing tool.
|
* @rsvd_next_header: 32-bit pointer to the next Secure Boot Module in the
|
* chain, if there is a next header.
|
* @rsvd: Reserved, padding structure to required size.
|
*
|
* See also QuartSecurityHeader_t in
|
* Quark_EDKII_v1.2.1.1/QuarkPlatformPkg/Include/QuarkBootRom.h
|
* from https://downloadcenter.intel.com/download/23197/Intel-Quark-SoC-X1000-Board-Support-Package-BSP
|
*/
|
struct quark_security_header {
|
u32 csh_signature;
|
u32 version;
|
u32 modulesize;
|
u32 security_version_number_index;
|
u32 security_version_number;
|
u32 rsvd_module_id;
|
u32 rsvd_module_vendor;
|
u32 rsvd_date;
|
u32 headersize;
|
u32 hash_algo;
|
u32 cryp_algo;
|
u32 keysize;
|
u32 signaturesize;
|
u32 rsvd_next_header;
|
u32 rsvd[2];
|
};
|
|
static const efi_char16_t efi_dummy_name[] = L"DUMMY";
|
|
static bool efi_no_storage_paranoia;
|
|
/*
|
* Some firmware implementations refuse to boot if there's insufficient
|
* space in the variable store. The implementation of garbage collection
|
* in some FW versions causes stale (deleted) variables to take up space
|
* longer than intended and space is only freed once the store becomes
|
* almost completely full.
|
*
|
* Enabling this option disables the space checks in
|
* efi_query_variable_store() and forces garbage collection.
|
*
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* Only enable this option if deleting EFI variables does not free up
|
* space in your variable store, e.g. if despite deleting variables
|
* you're unable to create new ones.
|
*/
|
static int __init setup_storage_paranoia(char *arg)
|
{
|
efi_no_storage_paranoia = true;
|
return 0;
|
}
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early_param("efi_no_storage_paranoia", setup_storage_paranoia);
|
|
/*
|
* Deleting the dummy variable which kicks off garbage collection
|
*/
|
void efi_delete_dummy_variable(void)
|
{
|
efi.set_variable_nonblocking((efi_char16_t *)efi_dummy_name,
|
&EFI_DUMMY_GUID,
|
EFI_VARIABLE_NON_VOLATILE |
|
EFI_VARIABLE_BOOTSERVICE_ACCESS |
|
EFI_VARIABLE_RUNTIME_ACCESS, 0, NULL);
|
}
|
|
/*
|
* In the nonblocking case we do not attempt to perform garbage
|
* collection if we do not have enough free space. Rather, we do the
|
* bare minimum check and give up immediately if the available space
|
* is below EFI_MIN_RESERVE.
|
*
|
* This function is intended to be small and simple because it is
|
* invoked from crash handler paths.
|
*/
|
static efi_status_t
|
query_variable_store_nonblocking(u32 attributes, unsigned long size)
|
{
|
efi_status_t status;
|
u64 storage_size, remaining_size, max_size;
|
|
status = efi.query_variable_info_nonblocking(attributes, &storage_size,
|
&remaining_size,
|
&max_size);
|
if (status != EFI_SUCCESS)
|
return status;
|
|
if (remaining_size - size < EFI_MIN_RESERVE)
|
return EFI_OUT_OF_RESOURCES;
|
|
return EFI_SUCCESS;
|
}
|
|
/*
|
* Some firmware implementations refuse to boot if there's insufficient space
|
* in the variable store. Ensure that we never use more than a safe limit.
|
*
|
* Return EFI_SUCCESS if it is safe to write 'size' bytes to the variable
|
* store.
|
*/
|
efi_status_t efi_query_variable_store(u32 attributes, unsigned long size,
|
bool nonblocking)
|
{
|
efi_status_t status;
|
u64 storage_size, remaining_size, max_size;
|
|
if (!(attributes & EFI_VARIABLE_NON_VOLATILE))
|
return 0;
|
|
if (nonblocking)
|
return query_variable_store_nonblocking(attributes, size);
|
|
status = efi.query_variable_info(attributes, &storage_size,
|
&remaining_size, &max_size);
|
if (status != EFI_SUCCESS)
|
return status;
|
|
/*
|
* We account for that by refusing the write if permitting it would
|
* reduce the available space to under 5KB. This figure was provided by
|
* Samsung, so should be safe.
|
*/
|
if ((remaining_size - size < EFI_MIN_RESERVE) &&
|
!efi_no_storage_paranoia) {
|
|
/*
|
* Triggering garbage collection may require that the firmware
|
* generate a real EFI_OUT_OF_RESOURCES error. We can force
|
* that by attempting to use more space than is available.
|
*/
|
unsigned long dummy_size = remaining_size + 1024;
|
void *dummy = kzalloc(dummy_size, GFP_KERNEL);
|
|
if (!dummy)
|
return EFI_OUT_OF_RESOURCES;
|
|
status = efi.set_variable((efi_char16_t *)efi_dummy_name,
|
&EFI_DUMMY_GUID,
|
EFI_VARIABLE_NON_VOLATILE |
|
EFI_VARIABLE_BOOTSERVICE_ACCESS |
|
EFI_VARIABLE_RUNTIME_ACCESS,
|
dummy_size, dummy);
|
|
if (status == EFI_SUCCESS) {
|
/*
|
* This should have failed, so if it didn't make sure
|
* that we delete it...
|
*/
|
efi_delete_dummy_variable();
|
}
|
|
kfree(dummy);
|
|
/*
|
* The runtime code may now have triggered a garbage collection
|
* run, so check the variable info again
|
*/
|
status = efi.query_variable_info(attributes, &storage_size,
|
&remaining_size, &max_size);
|
|
if (status != EFI_SUCCESS)
|
return status;
|
|
/*
|
* There still isn't enough room, so return an error
|
*/
|
if (remaining_size - size < EFI_MIN_RESERVE)
|
return EFI_OUT_OF_RESOURCES;
|
}
|
|
return EFI_SUCCESS;
|
}
|
EXPORT_SYMBOL_GPL(efi_query_variable_store);
|
|
/*
|
* The UEFI specification makes it clear that the operating system is
|
* free to do whatever it wants with boot services code after
|
* ExitBootServices() has been called. Ignoring this recommendation a
|
* significant bunch of EFI implementations continue calling into boot
|
* services code (SetVirtualAddressMap). In order to work around such
|
* buggy implementations we reserve boot services region during EFI
|
* init and make sure it stays executable. Then, after
|
* SetVirtualAddressMap(), it is discarded.
|
*
|
* However, some boot services regions contain data that is required
|
* by drivers, so we need to track which memory ranges can never be
|
* freed. This is done by tagging those regions with the
|
* EFI_MEMORY_RUNTIME attribute.
|
*
|
* Any driver that wants to mark a region as reserved must use
|
* efi_mem_reserve() which will insert a new EFI memory descriptor
|
* into efi.memmap (splitting existing regions if necessary) and tag
|
* it with EFI_MEMORY_RUNTIME.
|
*/
|
void __init efi_arch_mem_reserve(phys_addr_t addr, u64 size)
|
{
|
phys_addr_t new_phys, new_size;
|
struct efi_mem_range mr;
|
efi_memory_desc_t md;
|
int num_entries;
|
void *new;
|
|
if (efi_mem_desc_lookup(addr, &md) ||
|
md.type != EFI_BOOT_SERVICES_DATA) {
|
pr_err("Failed to lookup EFI memory descriptor for %pa\n", &addr);
|
return;
|
}
|
|
if (addr + size > md.phys_addr + (md.num_pages << EFI_PAGE_SHIFT)) {
|
pr_err("Region spans EFI memory descriptors, %pa\n", &addr);
|
return;
|
}
|
|
size += addr % EFI_PAGE_SIZE;
|
size = round_up(size, EFI_PAGE_SIZE);
|
addr = round_down(addr, EFI_PAGE_SIZE);
|
|
mr.range.start = addr;
|
mr.range.end = addr + size - 1;
|
mr.attribute = md.attribute | EFI_MEMORY_RUNTIME;
|
|
num_entries = efi_memmap_split_count(&md, &mr.range);
|
num_entries += efi.memmap.nr_map;
|
|
new_size = efi.memmap.desc_size * num_entries;
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|
new_phys = efi_memmap_alloc(num_entries);
|
if (!new_phys) {
|
pr_err("Could not allocate boot services memmap\n");
|
return;
|
}
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|
new = early_memremap_prot(new_phys, new_size,
|
pgprot_val(pgprot_encrypted(FIXMAP_PAGE_NORMAL)));
|
if (!new) {
|
pr_err("Failed to map new boot services memmap\n");
|
return;
|
}
|
|
efi_memmap_insert(&efi.memmap, new, &mr);
|
early_memunmap(new, new_size);
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|
efi_memmap_install(new_phys, num_entries);
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e820__range_update(addr, size, E820_TYPE_RAM, E820_TYPE_RESERVED);
|
e820__update_table(e820_table);
|
}
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|
/*
|
* Helper function for efi_reserve_boot_services() to figure out if we
|
* can free regions in efi_free_boot_services().
|
*
|
* Use this function to ensure we do not free regions owned by somebody
|
* else. We must only reserve (and then free) regions:
|
*
|
* - Not within any part of the kernel
|
* - Not the BIOS reserved area (E820_TYPE_RESERVED, E820_TYPE_NVS, etc)
|
*/
|
static bool can_free_region(u64 start, u64 size)
|
{
|
if (start + size > __pa_symbol(_text) && start <= __pa_symbol(_end))
|
return false;
|
|
if (!e820__mapped_all(start, start+size, E820_TYPE_RAM))
|
return false;
|
|
return true;
|
}
|
|
void __init efi_reserve_boot_services(void)
|
{
|
efi_memory_desc_t *md;
|
|
for_each_efi_memory_desc(md) {
|
u64 start = md->phys_addr;
|
u64 size = md->num_pages << EFI_PAGE_SHIFT;
|
bool already_reserved;
|
|
if (md->type != EFI_BOOT_SERVICES_CODE &&
|
md->type != EFI_BOOT_SERVICES_DATA)
|
continue;
|
|
already_reserved = memblock_is_region_reserved(start, size);
|
|
/*
|
* Because the following memblock_reserve() is paired
|
* with free_bootmem_late() for this region in
|
* efi_free_boot_services(), we must be extremely
|
* careful not to reserve, and subsequently free,
|
* critical regions of memory (like the kernel image) or
|
* those regions that somebody else has already
|
* reserved.
|
*
|
* A good example of a critical region that must not be
|
* freed is page zero (first 4Kb of memory), which may
|
* contain boot services code/data but is marked
|
* E820_TYPE_RESERVED by trim_bios_range().
|
*/
|
if (!already_reserved) {
|
memblock_reserve(start, size);
|
|
/*
|
* If we are the first to reserve the region, no
|
* one else cares about it. We own it and can
|
* free it later.
|
*/
|
if (can_free_region(start, size))
|
continue;
|
}
|
|
/*
|
* We don't own the region. We must not free it.
|
*
|
* Setting this bit for a boot services region really
|
* doesn't make sense as far as the firmware is
|
* concerned, but it does provide us with a way to tag
|
* those regions that must not be paired with
|
* free_bootmem_late().
|
*/
|
md->attribute |= EFI_MEMORY_RUNTIME;
|
}
|
}
|
|
void __init efi_free_boot_services(void)
|
{
|
phys_addr_t new_phys, new_size;
|
efi_memory_desc_t *md;
|
int num_entries = 0;
|
void *new, *new_md;
|
|
for_each_efi_memory_desc(md) {
|
unsigned long long start = md->phys_addr;
|
unsigned long long size = md->num_pages << EFI_PAGE_SHIFT;
|
size_t rm_size;
|
|
if (md->type != EFI_BOOT_SERVICES_CODE &&
|
md->type != EFI_BOOT_SERVICES_DATA) {
|
num_entries++;
|
continue;
|
}
|
|
/* Do not free, someone else owns it: */
|
if (md->attribute & EFI_MEMORY_RUNTIME) {
|
num_entries++;
|
continue;
|
}
|
|
/*
|
* Nasty quirk: if all sub-1MB memory is used for boot
|
* services, we can get here without having allocated the
|
* real mode trampoline. It's too late to hand boot services
|
* memory back to the memblock allocator, so instead
|
* try to manually allocate the trampoline if needed.
|
*
|
* I've seen this on a Dell XPS 13 9350 with firmware
|
* 1.4.4 with SGX enabled booting Linux via Fedora 24's
|
* grub2-efi on a hard disk. (And no, I don't know why
|
* this happened, but Linux should still try to boot rather
|
* panicing early.)
|
*/
|
rm_size = real_mode_size_needed();
|
if (rm_size && (start + rm_size) < (1<<20) && size >= rm_size) {
|
set_real_mode_mem(start, rm_size);
|
start += rm_size;
|
size -= rm_size;
|
}
|
|
free_bootmem_late(start, size);
|
}
|
|
if (!num_entries)
|
return;
|
|
new_size = efi.memmap.desc_size * num_entries;
|
new_phys = efi_memmap_alloc(num_entries);
|
if (!new_phys) {
|
pr_err("Failed to allocate new EFI memmap\n");
|
return;
|
}
|
|
new = memremap(new_phys, new_size, MEMREMAP_WB);
|
if (!new) {
|
pr_err("Failed to map new EFI memmap\n");
|
return;
|
}
|
|
/*
|
* Build a new EFI memmap that excludes any boot services
|
* regions that are not tagged EFI_MEMORY_RUNTIME, since those
|
* regions have now been freed.
|
*/
|
new_md = new;
|
for_each_efi_memory_desc(md) {
|
if (!(md->attribute & EFI_MEMORY_RUNTIME) &&
|
(md->type == EFI_BOOT_SERVICES_CODE ||
|
md->type == EFI_BOOT_SERVICES_DATA))
|
continue;
|
|
memcpy(new_md, md, efi.memmap.desc_size);
|
new_md += efi.memmap.desc_size;
|
}
|
|
memunmap(new);
|
|
if (efi_memmap_install(new_phys, num_entries)) {
|
pr_err("Could not install new EFI memmap\n");
|
return;
|
}
|
}
|
|
/*
|
* A number of config table entries get remapped to virtual addresses
|
* after entering EFI virtual mode. However, the kexec kernel requires
|
* their physical addresses therefore we pass them via setup_data and
|
* correct those entries to their respective physical addresses here.
|
*
|
* Currently only handles smbios which is necessary for some firmware
|
* implementation.
|
*/
|
int __init efi_reuse_config(u64 tables, int nr_tables)
|
{
|
int i, sz, ret = 0;
|
void *p, *tablep;
|
struct efi_setup_data *data;
|
|
if (!efi_setup)
|
return 0;
|
|
if (!efi_enabled(EFI_64BIT))
|
return 0;
|
|
data = early_memremap(efi_setup, sizeof(*data));
|
if (!data) {
|
ret = -ENOMEM;
|
goto out;
|
}
|
|
if (!data->smbios)
|
goto out_memremap;
|
|
sz = sizeof(efi_config_table_64_t);
|
|
p = tablep = early_memremap(tables, nr_tables * sz);
|
if (!p) {
|
pr_err("Could not map Configuration table!\n");
|
ret = -ENOMEM;
|
goto out_memremap;
|
}
|
|
for (i = 0; i < efi.systab->nr_tables; i++) {
|
efi_guid_t guid;
|
|
guid = ((efi_config_table_64_t *)p)->guid;
|
|
if (!efi_guidcmp(guid, SMBIOS_TABLE_GUID))
|
((efi_config_table_64_t *)p)->table = data->smbios;
|
p += sz;
|
}
|
early_memunmap(tablep, nr_tables * sz);
|
|
out_memremap:
|
early_memunmap(data, sizeof(*data));
|
out:
|
return ret;
|
}
|
|
static const struct dmi_system_id sgi_uv1_dmi[] = {
|
{ NULL, "SGI UV1",
|
{ DMI_MATCH(DMI_PRODUCT_NAME, "Stoutland Platform"),
|
DMI_MATCH(DMI_PRODUCT_VERSION, "1.0"),
|
DMI_MATCH(DMI_BIOS_VENDOR, "SGI.COM"),
|
}
|
},
|
{ } /* NULL entry stops DMI scanning */
|
};
|
|
void __init efi_apply_memmap_quirks(void)
|
{
|
/*
|
* Once setup is done earlier, unmap the EFI memory map on mismatched
|
* firmware/kernel architectures since there is no support for runtime
|
* services.
|
*/
|
if (!efi_runtime_supported()) {
|
pr_info("Setup done, disabling due to 32/64-bit mismatch\n");
|
efi_memmap_unmap();
|
}
|
|
/* UV2+ BIOS has a fix for this issue. UV1 still needs the quirk. */
|
if (dmi_check_system(sgi_uv1_dmi))
|
set_bit(EFI_OLD_MEMMAP, &efi.flags);
|
}
|
|
/*
|
* For most modern platforms the preferred method of powering off is via
|
* ACPI. However, there are some that are known to require the use of
|
* EFI runtime services and for which ACPI does not work at all.
|
*
|
* Using EFI is a last resort, to be used only if no other option
|
* exists.
|
*/
|
bool efi_reboot_required(void)
|
{
|
if (!acpi_gbl_reduced_hardware)
|
return false;
|
|
efi_reboot_quirk_mode = EFI_RESET_WARM;
|
return true;
|
}
|
|
bool efi_poweroff_required(void)
|
{
|
return acpi_gbl_reduced_hardware || acpi_no_s5;
|
}
|
|
#ifdef CONFIG_EFI_CAPSULE_QUIRK_QUARK_CSH
|
|
static int qrk_capsule_setup_info(struct capsule_info *cap_info, void **pkbuff,
|
size_t hdr_bytes)
|
{
|
struct quark_security_header *csh = *pkbuff;
|
|
/* Only process data block that is larger than the security header */
|
if (hdr_bytes < sizeof(struct quark_security_header))
|
return 0;
|
|
if (csh->csh_signature != QUARK_CSH_SIGNATURE ||
|
csh->headersize != QUARK_SECURITY_HEADER_SIZE)
|
return 1;
|
|
/* Only process data block if EFI header is included */
|
if (hdr_bytes < QUARK_SECURITY_HEADER_SIZE +
|
sizeof(efi_capsule_header_t))
|
return 0;
|
|
pr_debug("Quark security header detected\n");
|
|
if (csh->rsvd_next_header != 0) {
|
pr_err("multiple Quark security headers not supported\n");
|
return -EINVAL;
|
}
|
|
*pkbuff += csh->headersize;
|
cap_info->total_size = csh->headersize;
|
|
/*
|
* Update the first page pointer to skip over the CSH header.
|
*/
|
cap_info->phys[0] += csh->headersize;
|
|
/*
|
* cap_info->capsule should point at a virtual mapping of the entire
|
* capsule, starting at the capsule header. Our image has the Quark
|
* security header prepended, so we cannot rely on the default vmap()
|
* mapping created by the generic capsule code.
|
* Given that the Quark firmware does not appear to care about the
|
* virtual mapping, let's just point cap_info->capsule at our copy
|
* of the capsule header.
|
*/
|
cap_info->capsule = &cap_info->header;
|
|
return 1;
|
}
|
|
#define ICPU(family, model, quirk_handler) \
|
{ X86_VENDOR_INTEL, family, model, X86_FEATURE_ANY, \
|
(unsigned long)&quirk_handler }
|
|
static const struct x86_cpu_id efi_capsule_quirk_ids[] = {
|
ICPU(5, 9, qrk_capsule_setup_info), /* Intel Quark X1000 */
|
{ }
|
};
|
|
int efi_capsule_setup_info(struct capsule_info *cap_info, void *kbuff,
|
size_t hdr_bytes)
|
{
|
int (*quirk_handler)(struct capsule_info *, void **, size_t);
|
const struct x86_cpu_id *id;
|
int ret;
|
|
if (hdr_bytes < sizeof(efi_capsule_header_t))
|
return 0;
|
|
cap_info->total_size = 0;
|
|
id = x86_match_cpu(efi_capsule_quirk_ids);
|
if (id) {
|
/*
|
* The quirk handler is supposed to return
|
* - a value > 0 if the setup should continue, after advancing
|
* kbuff as needed
|
* - 0 if not enough hdr_bytes are available yet
|
* - a negative error code otherwise
|
*/
|
quirk_handler = (typeof(quirk_handler))id->driver_data;
|
ret = quirk_handler(cap_info, &kbuff, hdr_bytes);
|
if (ret <= 0)
|
return ret;
|
}
|
|
memcpy(&cap_info->header, kbuff, sizeof(cap_info->header));
|
|
cap_info->total_size += cap_info->header.imagesize;
|
|
return __efi_capsule_setup_info(cap_info);
|
}
|
|
#endif
|
