From 171539f5a90e3fdf7d17f5396fac79d7e44ad68e Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Thu, 15 Sep 2022 23:20:06 +0200 Subject: [PATCH] efi: libstub: install boot-time memory map as config table Expose the EFI boot time memory map to the kernel via a configuration table. This is arch agnostic and enables future changes that remove the dependency on DT on architectures that don't otherwise rely on it. Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/arm64-stub.c | 2 +- drivers/firmware/efi/libstub/efi-stub-helper.c | 2 +- drivers/firmware/efi/libstub/efistub.h | 3 ++- drivers/firmware/efi/libstub/mem.c | 27 +++++++++++++++++++++++--- drivers/firmware/efi/libstub/randomalloc.c | 2 +- drivers/firmware/efi/libstub/relocate.c | 2 +- include/linux/efi.h | 1 + 7 files changed, 31 insertions(+), 8 deletions(-) diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c index 83b5ae3..cd3bea2 100644 --- a/drivers/firmware/efi/libstub/arm64-stub.c +++ b/drivers/firmware/efi/libstub/arm64-stub.c @@ -47,7 +47,7 @@ static bool check_image_region(u64 base, u64 size) bool ret = false; int map_offset; - status = efi_get_memory_map(&map); + status = efi_get_memory_map(&map, false); if (status != EFI_SUCCESS) return false; diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c index a671eaa..e3ee838 100644 --- a/drivers/firmware/efi/libstub/efi-stub-helper.c +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c @@ -437,7 +437,7 @@ efi_status_t efi_exit_boot_services(void *handle, void *priv, struct efi_boot_memmap *map; efi_status_t status; - status = efi_get_memory_map(&map); + status = efi_get_memory_map(&map, true); if (status != EFI_SUCCESS) return status; diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h index f06d753..fc90e45 100644 --- a/drivers/firmware/efi/libstub/efistub.h +++ b/drivers/firmware/efi/libstub/efistub.h @@ -876,7 +876,8 @@ void efi_apply_loadoptions_quirk(const void **load_options, int *load_options_si char *efi_convert_cmdline(efi_loaded_image_t *image, int *cmd_line_len); -efi_status_t efi_get_memory_map(struct efi_boot_memmap **map); +efi_status_t efi_get_memory_map(struct efi_boot_memmap **map, + bool install_cfg_tbl); efi_status_t efi_allocate_pages(unsigned long size, unsigned long *addr, unsigned long max); diff --git a/drivers/firmware/efi/libstub/mem.c b/drivers/firmware/efi/libstub/mem.c index c92b7db..45841ef 100644 --- a/drivers/firmware/efi/libstub/mem.c +++ b/drivers/firmware/efi/libstub/mem.c @@ -9,14 +9,20 @@ * efi_get_memory_map() - get memory map * @map: pointer to memory map pointer to which to assign the * newly allocated memory map + * @install_cfg_tbl: whether or not to install the boot memory map as a + * configuration table * * Retrieve the UEFI memory map. The allocated memory leaves room for * up to EFI_MMAP_NR_SLACK_SLOTS additional memory map entries. * * Return: status code */ -efi_status_t efi_get_memory_map(struct efi_boot_memmap **map) +efi_status_t efi_get_memory_map(struct efi_boot_memmap **map, + bool install_cfg_tbl) { + int memtype = install_cfg_tbl ? EFI_ACPI_RECLAIM_MEMORY + : EFI_LOADER_DATA; + efi_guid_t tbl_guid = LINUX_EFI_BOOT_MEMMAP_GUID; struct efi_boot_memmap *m, tmp; efi_status_t status; unsigned long size; @@ -28,20 +34,35 @@ efi_status_t efi_get_memory_map(struct efi_boot_memmap **map) return EFI_LOAD_ERROR; size = tmp.map_size + tmp.desc_size * EFI_MMAP_NR_SLACK_SLOTS; - status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, sizeof(*m) + size, + status = efi_bs_call(allocate_pool, memtype, sizeof(*m) + size, (void **)&m); if (status != EFI_SUCCESS) return status; + if (install_cfg_tbl) { + /* + * Installing a configuration table might allocate memory, and + * this may modify the memory map. This means we should install + * the configuration table first, and re-install or delete it + * as needed. + */ + status = efi_bs_call(install_configuration_table, &tbl_guid, m); + if (status != EFI_SUCCESS) + goto free_map; + } + m->buff_size = m->map_size = size; status = efi_bs_call(get_memory_map, &m->map_size, m->map, &m->map_key, &m->desc_size, &m->desc_ver); if (status != EFI_SUCCESS) - goto free_map; + goto uninstall_table; *map = m; return EFI_SUCCESS; +uninstall_table: + if (install_cfg_tbl) + efi_bs_call(install_configuration_table, &tbl_guid, NULL); free_map: efi_bs_call(free_pool, m); return status; diff --git a/drivers/firmware/efi/libstub/randomalloc.c b/drivers/firmware/efi/libstub/randomalloc.c index 5d6000c..9fb5869 100644 --- a/drivers/firmware/efi/libstub/randomalloc.c +++ b/drivers/firmware/efi/libstub/randomalloc.c @@ -61,7 +61,7 @@ efi_status_t efi_random_alloc(unsigned long size, efi_status_t status; int map_offset; - status = efi_get_memory_map(&map); + status = efi_get_memory_map(&map, false); if (status != EFI_SUCCESS) return status; diff --git a/drivers/firmware/efi/libstub/relocate.c b/drivers/firmware/efi/libstub/relocate.c index cd80db3..bf6fbd5 100644 --- a/drivers/firmware/efi/libstub/relocate.c +++ b/drivers/firmware/efi/libstub/relocate.c @@ -28,7 +28,7 @@ efi_status_t efi_low_alloc_above(unsigned long size, unsigned long align, unsigned long nr_pages; int i; - status = efi_get_memory_map(&map); + status = efi_get_memory_map(&map, false); if (status != EFI_SUCCESS) goto fail; diff --git a/include/linux/efi.h b/include/linux/efi.h index 778ddb2..252b9b3 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -410,6 +410,7 @@ void efi_native_runtime_setup(void); #define LINUX_EFI_INITRD_MEDIA_GUID EFI_GUID(0x5568e427, 0x68fc, 0x4f3d, 0xac, 0x74, 0xca, 0x55, 0x52, 0x31, 0xcc, 0x68) #define LINUX_EFI_MOK_VARIABLE_TABLE_GUID EFI_GUID(0xc451ed2b, 0x9694, 0x45d3, 0xba, 0xba, 0xed, 0x9f, 0x89, 0x88, 0xa3, 0x89) #define LINUX_EFI_COCO_SECRET_AREA_GUID EFI_GUID(0xadf956ad, 0xe98c, 0x484c, 0xae, 0x11, 0xb5, 0x1c, 0x7d, 0x33, 0x64, 0x47) +#define LINUX_EFI_BOOT_MEMMAP_GUID EFI_GUID(0x800f683f, 0xd08b, 0x423a, 0xa2, 0x93, 0x96, 0x5c, 0x3c, 0x6f, 0xe2, 0xb4) #define RISCV_EFI_BOOT_PROTOCOL_GUID EFI_GUID(0xccd15fec, 0x6f73, 0x4eec, 0x83, 0x95, 0x3e, 0x69, 0xe4, 0xb9, 0x40, 0xbf) -- 2.7.4