1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Load ELF vmlinux file for the kexec_file_load syscall.
4 *
5 * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
6 * Copyright (C) 2004 IBM Corp.
7 * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
8 * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
9 * Copyright (C) 2016 IBM Corporation
10 *
11 * Based on kexec-tools' kexec-elf-exec.c and kexec-elf-ppc64.c.
12 * Heavily modified for the kernel by
13 * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>.
14 */
15
16 #define pr_fmt(fmt) "kexec_elf: " fmt
17
18 #include <linux/elf.h>
19 #include <linux/kexec.h>
20 #include <linux/libfdt.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_fdt.h>
24 #include <linux/slab.h>
25 #include <linux/types.h>
26 #include <asm/kexec_ranges.h>
27
28 static void *elf64_load(struct kimage *image, char *kernel_buf,
29 unsigned long kernel_len, char *initrd,
30 unsigned long initrd_len, char *cmdline,
31 unsigned long cmdline_len)
32 {
33 int ret;
34 unsigned long kernel_load_addr;
35 unsigned long initrd_load_addr = 0, fdt_load_addr;
36 void *fdt;
37 const void *slave_code;
38 struct elfhdr ehdr;
39 char *modified_cmdline = NULL;
40 struct crash_mem *rmem = NULL;
41 struct kexec_elf_info elf_info;
42 struct kexec_buf kbuf = { .image = image, .buf_min = 0,
43 .buf_max = ppc64_rma_size };
44 struct kexec_buf pbuf = { .image = image, .buf_min = 0,
45 .buf_max = ppc64_rma_size, .top_down = true,
46 .mem = KEXEC_BUF_MEM_UNKNOWN };
47
48 ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info);
49 if (ret)
50 return ERR_PTR(ret);
51
52 if (IS_ENABLED(CONFIG_CRASH_DUMP) && image->type == KEXEC_TYPE_CRASH) {
53 /* min & max buffer values for kdump case */
54 kbuf.buf_min = pbuf.buf_min = crashk_res.start;
55 kbuf.buf_max = pbuf.buf_max =
56 ((crashk_res.end < ppc64_rma_size) ?
57 crashk_res.end : (ppc64_rma_size - 1));
58 }
59
60 ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr);
61 if (ret)
62 goto out;
63
64 kexec_dprintk("Loaded the kernel at 0x%lx\n", kernel_load_addr);
65
66 ret = kexec_load_purgatory(image, &pbuf);
67 if (ret) {
68 pr_err("Loading purgatory failed.\n");
69 goto out;
70 }
71
72 kexec_dprintk("Loaded purgatory at 0x%lx\n", pbuf.mem);
73
74 /* Load additional segments needed for panic kernel */
75 if (IS_ENABLED(CONFIG_CRASH_DUMP) && image->type == KEXEC_TYPE_CRASH) {
76 ret = load_crashdump_segments_ppc64(image, &kbuf);
77 if (ret) {
78 pr_err("Failed to load kdump kernel segments\n");
79 goto out;
80 }
81
82 /* Setup cmdline for kdump kernel case */
83 modified_cmdline = setup_kdump_cmdline(image, cmdline,
84 cmdline_len);
85 if (!modified_cmdline) {
86 pr_err("Setting up cmdline for kdump kernel failed\n");
87 ret = -EINVAL;
88 goto out;
89 }
90 cmdline = modified_cmdline;
91 }
92
93 if (initrd != NULL) {
94 kbuf.buffer = initrd;
95 kbuf.bufsz = kbuf.memsz = initrd_len;
96 kbuf.buf_align = PAGE_SIZE;
97 kbuf.top_down = false;
98 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
99 ret = kexec_add_buffer(&kbuf);
100 if (ret)
101 goto out;
102 initrd_load_addr = kbuf.mem;
103
104 kexec_dprintk("Loaded initrd at 0x%lx\n", initrd_load_addr);
105 }
106
107 ret = get_reserved_memory_ranges(&rmem);
108 if (ret)
109 goto out;
110
111 fdt = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
112 initrd_len, cmdline,
113 kexec_extra_fdt_size_ppc64(image, rmem));
114 if (!fdt) {
115 pr_err("Error setting up the new device tree.\n");
116 ret = -EINVAL;
117 goto out;
118 }
119
120 ret = setup_new_fdt_ppc64(image, fdt, rmem);
121 if (ret)
122 goto out_free_fdt;
123
124 if (!IS_ENABLED(CONFIG_CRASH_HOTPLUG) || image->type != KEXEC_TYPE_CRASH)
125 fdt_pack(fdt);
126
127 kbuf.buffer = fdt;
128 kbuf.bufsz = kbuf.memsz = fdt_totalsize(fdt);
129 kbuf.buf_align = PAGE_SIZE;
130 kbuf.top_down = true;
131 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
132 ret = kexec_add_buffer(&kbuf);
133 if (ret)
134 goto out_free_fdt;
135
136 /* FDT will be freed in arch_kimage_file_post_load_cleanup */
137 image->arch.fdt = fdt;
138
139 fdt_load_addr = kbuf.mem;
140
141 kexec_dprintk("Loaded device tree at 0x%lx\n", fdt_load_addr);
142
143 slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
144 ret = setup_purgatory_ppc64(image, slave_code, fdt, kernel_load_addr,
145 fdt_load_addr);
146 if (ret)
147 pr_err("Error setting up the purgatory.\n");
148
149 goto out;
150
151 out_free_fdt:
152 kvfree(fdt);
153 out:
154 kfree(rmem);
155 kfree(modified_cmdline);
156 kexec_free_elf_info(&elf_info);
157
158 return ret ? ERR_PTR(ret) : NULL;
159 }
160
161 const struct kexec_file_ops kexec_elf64_ops = {
162 .probe = kexec_elf_probe,
163 .load = elf64_load,
164 };
165
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