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_fdt.h> 23 #include <linux/slab.h> 24 #include <linux/types.h> 25 26 static void *elf64_load(struct kimage *image, char *kernel_buf, 27 unsigned long kernel_len, char *initrd, 28 unsigned long initrd_len, char *cmdline, 29 unsigned long cmdline_len) 30 { 31 int ret; 32 unsigned int fdt_size; 33 unsigned long kernel_load_addr; 34 unsigned long initrd_load_addr = 0, fdt_load_addr; 35 void *fdt; 36 const void *slave_code; 37 struct elfhdr ehdr; 38 char *modified_cmdline = NULL; 39 struct kexec_elf_info elf_info; 40 struct kexec_buf kbuf = { .image = image, .buf_min = 0, 41 .buf_max = ppc64_rma_size }; 42 struct kexec_buf pbuf = { .image = image, .buf_min = 0, 43 .buf_max = ppc64_rma_size, .top_down = true, 44 .mem = KEXEC_BUF_MEM_UNKNOWN }; 45 46 ret = kexec_build_elf_info(kernel_buf, kernel_len, &ehdr, &elf_info); 47 if (ret) 48 goto out; 49 50 if (image->type == KEXEC_TYPE_CRASH) { 51 /* min & max buffer values for kdump case */ 52 kbuf.buf_min = pbuf.buf_min = crashk_res.start; 53 kbuf.buf_max = pbuf.buf_max = 54 ((crashk_res.end < ppc64_rma_size) ? 55 crashk_res.end : (ppc64_rma_size - 1)); 56 } 57 58 ret = kexec_elf_load(image, &ehdr, &elf_info, &kbuf, &kernel_load_addr); 59 if (ret) 60 goto out; 61 62 pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr); 63 64 ret = kexec_load_purgatory(image, &pbuf); 65 if (ret) { 66 pr_err("Loading purgatory failed.\n"); 67 goto out; 68 } 69 70 pr_debug("Loaded purgatory at 0x%lx\n", pbuf.mem); 71 72 /* Load additional segments needed for panic kernel */ 73 if (image->type == KEXEC_TYPE_CRASH) { 74 ret = load_crashdump_segments_ppc64(image, &kbuf); 75 if (ret) { 76 pr_err("Failed to load kdump kernel segments\n"); 77 goto out; 78 } 79 80 /* Setup cmdline for kdump kernel case */ 81 modified_cmdline = setup_kdump_cmdline(image, cmdline, 82 cmdline_len); 83 if (!modified_cmdline) { 84 pr_err("Setting up cmdline for kdump kernel failed\n"); 85 ret = -EINVAL; 86 goto out; 87 } 88 cmdline = modified_cmdline; 89 } 90 91 if (initrd != NULL) { 92 kbuf.buffer = initrd; 93 kbuf.bufsz = kbuf.memsz = initrd_len; 94 kbuf.buf_align = PAGE_SIZE; 95 kbuf.top_down = false; 96 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 97 ret = kexec_add_buffer(&kbuf); 98 if (ret) 99 goto out; 100 initrd_load_addr = kbuf.mem; 101 102 pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr); 103 } 104 105 fdt_size = kexec_fdt_totalsize_ppc64(image); 106 fdt = kmalloc(fdt_size, GFP_KERNEL); 107 if (!fdt) { 108 pr_err("Not enough memory for the device tree.\n"); 109 ret = -ENOMEM; 110 goto out; 111 } 112 ret = fdt_open_into(initial_boot_params, fdt, fdt_size); 113 if (ret < 0) { 114 pr_err("Error setting up the new device tree.\n"); 115 ret = -EINVAL; 116 goto out; 117 } 118 119 ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr, 120 initrd_len, cmdline); 121 if (ret) 122 goto out; 123 124 fdt_pack(fdt); 125 126 kbuf.buffer = fdt; 127 kbuf.bufsz = kbuf.memsz = fdt_size; 128 kbuf.buf_align = PAGE_SIZE; 129 kbuf.top_down = true; 130 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 131 ret = kexec_add_buffer(&kbuf); 132 if (ret) 133 goto out; 134 fdt_load_addr = kbuf.mem; 135 136 pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr); 137 138 slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset; 139 ret = setup_purgatory_ppc64(image, slave_code, fdt, kernel_load_addr, 140 fdt_load_addr); 141 if (ret) 142 pr_err("Error setting up the purgatory.\n"); 143 144 out: 145 kfree(modified_cmdline); 146 kexec_free_elf_info(&elf_info); 147 148 /* Make kimage_file_post_load_cleanup free the fdt buffer for us. */ 149 return ret ? ERR_PTR(ret) : fdt; 150 } 151 152 const struct kexec_file_ops kexec_elf64_ops = { 153 .probe = kexec_elf_probe, 154 .load = elf64_load, 155 }; 156