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