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 27 static void *elf64_load(struct kimage *image, char *kernel_buf, 28 unsigned long kernel_len, char *initrd, 29 unsigned long initrd_len, char *cmdline, 30 unsigned long cmdline_len) 31 { 32 int ret; 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 return ERR_PTR(ret); 49 50 if (IS_ENABLED(CONFIG_CRASH_DUMP) && 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 kexec_dprintk("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 kexec_dprintk("Loaded purgatory at 0x%lx\n", pbuf.mem); 71 72 /* Load additional segments needed for panic kernel */ 73 if (IS_ENABLED(CONFIG_CRASH_DUMP) && 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 kexec_dprintk("Loaded initrd at 0x%lx\n", initrd_load_addr); 103 } 104 105 fdt = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr, 106 initrd_len, cmdline, 107 kexec_extra_fdt_size_ppc64(image)); 108 if (!fdt) { 109 pr_err("Error setting up the new device tree.\n"); 110 ret = -EINVAL; 111 goto out; 112 } 113 114 ret = setup_new_fdt_ppc64(image, fdt, initrd_load_addr, 115 initrd_len, cmdline); 116 if (ret) 117 goto out_free_fdt; 118 119 fdt_pack(fdt); 120 121 kbuf.buffer = fdt; 122 kbuf.bufsz = kbuf.memsz = fdt_totalsize(fdt); 123 kbuf.buf_align = PAGE_SIZE; 124 kbuf.top_down = true; 125 kbuf.mem = KEXEC_BUF_MEM_UNKNOWN; 126 ret = kexec_add_buffer(&kbuf); 127 if (ret) 128 goto out_free_fdt; 129 130 /* FDT will be freed in arch_kimage_file_post_load_cleanup */ 131 image->arch.fdt = fdt; 132 133 fdt_load_addr = kbuf.mem; 134 135 kexec_dprintk("Loaded device tree at 0x%lx\n", fdt_load_addr); 136 137 slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset; 138 ret = setup_purgatory_ppc64(image, slave_code, fdt, kernel_load_addr, 139 fdt_load_addr); 140 if (ret) 141 pr_err("Error setting up the purgatory.\n"); 142 143 goto out; 144 145 out_free_fdt: 146 kvfree(fdt); 147 out: 148 kfree(modified_cmdline); 149 kexec_free_elf_info(&elf_info); 150 151 return ret ? ERR_PTR(ret) : NULL; 152 } 153 154 const struct kexec_file_ops kexec_elf64_ops = { 155 .probe = kexec_elf_probe, 156 .load = elf64_load, 157 }; 158