1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * efi_selftest_debug_support
4  *
5  * Copyright (c) 2025 Ying-Chun Liu, Linaro Ltd. <paul.liu@linaro.org>
6  *
7  * Test the EFI_DEBUG_SUPPORT
8  */
9 
10 #include <efi_loader.h>
11 #include <efi_selftest.h>
12 #include <linux/sizes.h>
13 
14 /**
15  * efi_st_debug_support_execute() - execute test
16  *
17  * Test EFI_DEBUG_SUPPORT tables.
18  *
19  * Return:	status code
20  */
efi_st_debug_support_execute(void)21 static int efi_st_debug_support_execute(void)
22 {
23 	struct efi_debug_image_info_table_header *efi_st_debug_info_table_header = NULL;
24 	efi_guid_t efi_debug_image_info_table_guid = EFI_DEBUG_IMAGE_INFO_TABLE_GUID;
25 	struct efi_mem_desc *memory_map;
26 	efi_uintn_t map_size = 0;
27 	efi_uintn_t map_key;
28 	efi_uintn_t desc_size;
29 	u32 desc_version;
30 	efi_status_t ret;
31 
32 	/* get EFI_DEBUG_IMAGE_INFO_TABLE */
33 	efi_st_debug_info_table_header = efi_st_get_config_table(&efi_debug_image_info_table_guid);
34 
35 	if (!efi_st_debug_info_table_header) {
36 		efi_st_error("Missing EFI_DEBUG_IMAGE_INFO_TABLE\n");
37 		return EFI_ST_FAILURE;
38 	}
39 
40 	/* Load memory map */
41 	ret = st_boottime->get_memory_map(&map_size, NULL, &map_key, &desc_size,
42 					  &desc_version);
43 	if (ret != EFI_BUFFER_TOO_SMALL) {
44 		efi_st_error
45 			("GetMemoryMap did not return EFI_BUFFER_TOO_SMALL\n");
46 		return EFI_ST_FAILURE;
47 	}
48 	/* Allocate extra space for newly allocated memory */
49 	map_size += sizeof(struct efi_mem_desc);
50 	ret = st_boottime->allocate_pool(EFI_BOOT_SERVICES_DATA, map_size,
51 					 (void **)&memory_map);
52 	if (ret != EFI_SUCCESS) {
53 		efi_st_error("AllocatePool failed\n");
54 		return EFI_ST_FAILURE;
55 	}
56 	ret = st_boottime->get_memory_map(&map_size, memory_map, &map_key,
57 					  &desc_size, &desc_version);
58 	if (ret != EFI_SUCCESS) {
59 		efi_st_error("GetMemoryMap failed\n");
60 		return EFI_ST_FAILURE;
61 	}
62 	/* Find the system table pointer */
63 	for (efi_uintn_t i = 0; map_size; ++i, map_size -= desc_size) {
64 		struct efi_mem_desc *entry = &memory_map[i];
65 		u64 end;
66 
67 		if (entry->type != EFI_RUNTIME_SERVICES_DATA)
68 			continue;
69 
70 		end = entry->physical_start +
71 		      (entry->num_pages << EFI_PAGE_SHIFT);
72 		for (u64 pos = ALIGN(entry->physical_start, SZ_4M);
73 		     pos <= end; pos += SZ_4M) {
74 			struct efi_system_table_pointer *systab_pointer =
75 				(void *)(uintptr_t)pos;
76 
77 			/* check for overflow */
78 			if (pos < entry->physical_start)
79 				break;
80 			if (systab_pointer->signature ==
81 			    EFI_SYSTEM_TABLE_SIGNATURE) {
82 				if (systab_pointer->efi_system_table_base !=
83 				    (uintptr_t)st_systable) {
84 					efi_st_error("Wrong system table address\n");
85 					ret = EFI_ST_FAILURE;
86 					goto out;
87 				}
88 				ret = EFI_ST_SUCCESS;
89 				goto out;
90 			}
91 		}
92 	}
93 	efi_st_error("System table pointer not found\n");
94 	ret = EFI_ST_FAILURE;
95 
96 out:
97 	st_boottime->free_pool(memory_map);
98 
99 	return ret;
100 }
101 
102 EFI_UNIT_TEST(debug_support) = {
103 	.name = "debug_support",
104 	.phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
105 	.execute = efi_st_debug_support_execute,
106 };
107