diff options
| -rw-r--r-- | arch/arm64/kernel/efi.c | 52 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/Makefile | 2 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/arm64-stub.c | 17 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/efistub.h | 28 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/smbios.c | 48 | ||||
| -rw-r--r-- | include/linux/efi.h | 1 |
6 files changed, 128 insertions, 20 deletions
diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index 8d36e66a6e64..ee53f2a0aa03 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -13,6 +13,14 @@ #include <asm/efi.h> +static bool region_is_misaligned(const efi_memory_desc_t *md) +{ + if (PAGE_SIZE == EFI_PAGE_SIZE) + return false; + return !PAGE_ALIGNED(md->phys_addr) || + !PAGE_ALIGNED(md->num_pages << EFI_PAGE_SHIFT); +} + /* * Only regions of type EFI_RUNTIME_SERVICES_CODE need to be * executable, everything else can be mapped with the XN bits @@ -26,14 +34,22 @@ static __init pteval_t create_mapping_protection(efi_memory_desc_t *md) if (type == EFI_MEMORY_MAPPED_IO) return PROT_DEVICE_nGnRE; - if (WARN_ONCE(!PAGE_ALIGNED(md->phys_addr), - "UEFI Runtime regions are not aligned to 64 KB -- buggy firmware?")) + if (region_is_misaligned(md)) { + static bool __initdata code_is_misaligned; + /* - * If the region is not aligned to the page size of the OS, we - * can not use strict permissions, since that would also affect - * the mapping attributes of the adjacent regions. + * Regions that are not aligned to the OS page size cannot be + * mapped with strict permissions, as those might interfere + * with the permissions that are needed by the adjacent + * region's mapping. However, if we haven't encountered any + * misaligned runtime code regions so far, we can safely use + * non-executable permissions for non-code regions. */ - return pgprot_val(PAGE_KERNEL_EXEC); + code_is_misaligned |= (type == EFI_RUNTIME_SERVICES_CODE); + + return code_is_misaligned ? pgprot_val(PAGE_KERNEL_EXEC) + : pgprot_val(PAGE_KERNEL); + } /* R-- */ if ((attr & (EFI_MEMORY_XP | EFI_MEMORY_RO)) == @@ -64,19 +80,16 @@ int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md) bool page_mappings_only = (md->type == EFI_RUNTIME_SERVICES_CODE || md->type == EFI_RUNTIME_SERVICES_DATA); - if (!PAGE_ALIGNED(md->phys_addr) || - !PAGE_ALIGNED(md->num_pages << EFI_PAGE_SHIFT)) { - /* - * If the end address of this region is not aligned to page - * size, the mapping is rounded up, and may end up sharing a - * page frame with the next UEFI memory region. If we create - * a block entry now, we may need to split it again when mapping - * the next region, and support for that is going to be removed - * from the MMU routines. So avoid block mappings altogether in - * that case. - */ + /* + * If this region is not aligned to the page size used by the OS, the + * mapping will be rounded outwards, and may end up sharing a page + * frame with an adjacent runtime memory region. Given that the page + * table descriptor covering the shared page will be rewritten when the + * adjacent region gets mapped, we must avoid block mappings here so we + * don't have to worry about splitting them when that happens. + */ + if (region_is_misaligned(md)) page_mappings_only = true; - } create_pgd_mapping(mm, md->phys_addr, md->virt_addr, md->num_pages << EFI_PAGE_SHIFT, @@ -103,6 +116,9 @@ int __init efi_set_mapping_permissions(struct mm_struct *mm, BUG_ON(md->type != EFI_RUNTIME_SERVICES_CODE && md->type != EFI_RUNTIME_SERVICES_DATA); + if (region_is_misaligned(md)) + return 0; + /* * Calling apply_to_page_range() is only safe on regions that are * guaranteed to be mapped down to pages. Since we are only called diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index b1601aad7e1a..ef5045a53ce0 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -82,7 +82,7 @@ $(obj)/lib-%.o: $(srctree)/lib/%.c FORCE lib-$(CONFIG_EFI_GENERIC_STUB) += efi-stub.o string.o intrinsics.o systable.o lib-$(CONFIG_ARM) += arm32-stub.o -lib-$(CONFIG_ARM64) += arm64-stub.o +lib-$(CONFIG_ARM64) += arm64-stub.o smbios.o lib-$(CONFIG_X86) += x86-stub.o lib-$(CONFIG_RISCV) += riscv-stub.o lib-$(CONFIG_LOONGARCH) += loongarch-stub.o diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 259e4b852d63..f9de5217ea65 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -15,6 +15,21 @@ #include "efistub.h" +static bool system_needs_vamap(void) +{ + const u8 *type1_family = efi_get_smbios_string(1, family); + + /* + * Ampere Altra machines crash in SetTime() if SetVirtualAddressMap() + * has not been called prior. + */ + if (!type1_family || strcmp(type1_family, "Altra")) + return false; + + efi_warn("Working around broken SetVirtualAddressMap()\n"); + return true; +} + efi_status_t check_platform_features(void) { u64 tg; @@ -24,7 +39,7 @@ efi_status_t check_platform_features(void) * UEFI runtime regions 1:1 and so calling SetVirtualAddressMap() is * unnecessary. */ - if (VA_BITS_MIN >= 48) + if (VA_BITS_MIN >= 48 && !system_needs_vamap()) efi_novamap = true; /* UEFI mandates support for 4 KB granularity, no need to check */ diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index a30fb5d8ef05..eb03d5a9aac8 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -975,4 +975,32 @@ efi_enable_reset_attack_mitigation(void) { } void efi_retrieve_tpm2_eventlog(void); +struct efi_smbios_record { + u8 type; + u8 length; + u16 handle; +}; + +struct efi_smbios_type1_record { + struct efi_smbios_record header; + + u8 manufacturer; + u8 product_name; + u8 version; + u8 serial_number; + efi_guid_t uuid; + u8 wakeup_type; + u8 sku_number; + u8 family; +}; + +#define efi_get_smbios_string(__type, __name) ({ \ + int size = sizeof(struct efi_smbios_type ## __type ## _record); \ + int off = offsetof(struct efi_smbios_type ## __type ## _record, \ + __name); \ + __efi_get_smbios_string(__type, off, size); \ +}) + +const u8 *__efi_get_smbios_string(u8 type, int offset, int recsize); + #endif diff --git a/drivers/firmware/efi/libstub/smbios.c b/drivers/firmware/efi/libstub/smbios.c new file mode 100644 index 000000000000..460418b7f5f5 --- /dev/null +++ b/drivers/firmware/efi/libstub/smbios.c @@ -0,0 +1,48 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright 2022 Google LLC +// Author: Ard Biesheuvel <ardb@google.com> + +#include <linux/efi.h> + +#include "efistub.h" + +typedef struct efi_smbios_protocol efi_smbios_protocol_t; + +struct efi_smbios_protocol { + efi_status_t (__efiapi *add)(efi_smbios_protocol_t *, efi_handle_t, + u16 *, struct efi_smbios_record *); + efi_status_t (__efiapi *update_string)(efi_smbios_protocol_t *, u16 *, + unsigned long *, u8 *); + efi_status_t (__efiapi *remove)(efi_smbios_protocol_t *, u16); + efi_status_t (__efiapi *get_next)(efi_smbios_protocol_t *, u16 *, u8 *, + struct efi_smbios_record **, + efi_handle_t *); + + u8 major_version; + u8 minor_version; +}; + +const u8 *__efi_get_smbios_string(u8 type, int offset, int recsize) +{ + struct efi_smbios_record *record; + efi_smbios_protocol_t *smbios; + efi_status_t status; + u16 handle = 0xfffe; + const u8 *strtable; + + status = efi_bs_call(locate_protocol, &EFI_SMBIOS_PROTOCOL_GUID, NULL, + (void **)&smbios) ?: + efi_call_proto(smbios, get_next, &handle, &type, &record, NULL); + if (status != EFI_SUCCESS) + return NULL; + + strtable = (u8 *)record + recsize; + for (int i = 1; i < ((u8 *)record)[offset]; i++) { + int len = strlen(strtable); + + if (!len) + return NULL; + strtable += len + 1; + } + return strtable; +} diff --git a/include/linux/efi.h b/include/linux/efi.h index 929d559ad41d..7603fc58c47c 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -389,6 +389,7 @@ void efi_native_runtime_setup(void); #define EFI_LOAD_FILE2_PROTOCOL_GUID EFI_GUID(0x4006c0c1, 0xfcb3, 0x403e, 0x99, 0x6d, 0x4a, 0x6c, 0x87, 0x24, 0xe0, 0x6d) #define EFI_RT_PROPERTIES_TABLE_GUID EFI_GUID(0xeb66918a, 0x7eef, 0x402a, 0x84, 0x2e, 0x93, 0x1d, 0x21, 0xc3, 0x8a, 0xe9) #define EFI_DXE_SERVICES_TABLE_GUID EFI_GUID(0x05ad34ba, 0x6f02, 0x4214, 0x95, 0x2e, 0x4d, 0xa0, 0x39, 0x8e, 0x2b, 0xb9) +#define EFI_SMBIOS_PROTOCOL_GUID EFI_GUID(0x03583ff6, 0xcb36, 0x4940, 0x94, 0x7e, 0xb9, 0xb3, 0x9f, 0x4a, 0xfa, 0xf7) #define EFI_IMAGE_SECURITY_DATABASE_GUID EFI_GUID(0xd719b2cb, 0x3d3a, 0x4596, 0xa3, 0xbc, 0xda, 0xd0, 0x0e, 0x67, 0x65, 0x6f) #define EFI_SHIM_LOCK_GUID EFI_GUID(0x605dab50, 0xe046, 0x4300, 0xab, 0xb6, 0x3d, 0xd8, 0x10, 0xdd, 0x8b, 0x23) |