[PATCHv11 2/9] efi/x86: Get full memory map in allocate_e820()
From: Kirill A. Shutemov <hidden>
Date: 2023-05-13 22:05:03
Also in:
linux-efi, linux-mm, lkml
Subsystem:
extensible firmware interface (efi), the rest · Maintainers:
Ard Biesheuvel, Linus Torvalds
Currently allocate_e820() is only interested in the size of map and size of memory descriptor to determine how many e820 entries the kernel needs. UEFI Specification version 2.9 introduces a new memory type -- unaccepted memory. To track unaccepted memory kernel needs to allocate a bitmap. The size of the bitmap is dependent on the maximum physical address present in the system. A full memory map is required to find the maximum address. Modify allocate_e820() to get a full memory map. Signed-off-by: Kirill A. Shutemov <redacted> Reviewed-by: Borislav Petkov <redacted> Acked-by: Ard Biesheuvel <ardb@kernel.org> --- drivers/firmware/efi/libstub/x86-stub.c | 26 +++++++++++-------------- 1 file changed, 11 insertions(+), 15 deletions(-)
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index a0bfd31358ba..fff81843169c 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c@@ -681,28 +681,24 @@ static efi_status_t allocate_e820(struct boot_params *params, struct setup_data **e820ext, u32 *e820ext_size) { - unsigned long map_size, desc_size, map_key; + struct efi_boot_memmap *map; efi_status_t status; - __u32 nr_desc, desc_version; + __u32 nr_desc; - /* Only need the size of the mem map and size of each mem descriptor */ - map_size = 0; - status = efi_bs_call(get_memory_map, &map_size, NULL, &map_key, - &desc_size, &desc_version); - if (status != EFI_BUFFER_TOO_SMALL) - return (status != EFI_SUCCESS) ? status : EFI_UNSUPPORTED; + status = efi_get_memory_map(&map, false); + if (status != EFI_SUCCESS) + return status; - nr_desc = map_size / desc_size + EFI_MMAP_NR_SLACK_SLOTS; - - if (nr_desc > ARRAY_SIZE(params->e820_table)) { - u32 nr_e820ext = nr_desc - ARRAY_SIZE(params->e820_table); + 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 (status != EFI_SUCCESS) - return status; } - return EFI_SUCCESS; + efi_bs_call(free_pool, map); + return status; } struct exit_boot_struct {
--
2.39.3