1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Kernel module help for powerpc. 3 Copyright (C) 2001, 2003 Rusty Russell IBM Corporation. 4 Copyright (C) 2008 Freescale Semiconductor, Inc. 5 6 */ 7 #include <linux/elf.h> 8 #include <linux/moduleloader.h> 9 #include <linux/err.h> 10 #include <linux/vmalloc.h> 11 #include <linux/mm.h> 12 #include <linux/bug.h> 13 #include <linux/execmem.h> 14 #include <asm/module.h> 15 #include <linux/uaccess.h> 16 #include <asm/firmware.h> 17 #include <linux/sort.h> 18 #include <asm/setup.h> 19 #include <asm/sections.h> 20 21 static LIST_HEAD(module_bug_list); 22 23 static const Elf_Shdr *find_section(const Elf_Ehdr *hdr, 24 const Elf_Shdr *sechdrs, 25 const char *name) 26 { 27 char *secstrings; 28 unsigned int i; 29 30 secstrings = (char *)hdr + sechdrs[hdr->e_shstrndx].sh_offset; 31 for (i = 1; i < hdr->e_shnum; i++) 32 if (strcmp(secstrings+sechdrs[i].sh_name, name) == 0) 33 return &sechdrs[i]; 34 return NULL; 35 } 36 37 int module_finalize(const Elf_Ehdr *hdr, 38 const Elf_Shdr *sechdrs, struct module *me) 39 { 40 const Elf_Shdr *sect; 41 int rc; 42 43 rc = module_finalize_ftrace(me, sechdrs); 44 if (rc) 45 return rc; 46 47 /* Apply feature fixups */ 48 sect = find_section(hdr, sechdrs, "__ftr_fixup"); 49 if (sect != NULL) 50 do_feature_fixups(cur_cpu_spec->cpu_features, 51 (void *)sect->sh_addr, 52 (void *)sect->sh_addr + sect->sh_size); 53 54 sect = find_section(hdr, sechdrs, "__mmu_ftr_fixup"); 55 if (sect != NULL) 56 do_feature_fixups(cur_cpu_spec->mmu_features, 57 (void *)sect->sh_addr, 58 (void *)sect->sh_addr + sect->sh_size); 59 60 #ifdef CONFIG_PPC64 61 sect = find_section(hdr, sechdrs, "__fw_ftr_fixup"); 62 if (sect != NULL) 63 do_feature_fixups(powerpc_firmware_features, 64 (void *)sect->sh_addr, 65 (void *)sect->sh_addr + sect->sh_size); 66 #endif /* CONFIG_PPC64 */ 67 68 #ifdef CONFIG_PPC64_ELF_ABI_V1 69 sect = find_section(hdr, sechdrs, ".opd"); 70 if (sect != NULL) { 71 me->arch.start_opd = sect->sh_addr; 72 me->arch.end_opd = sect->sh_addr + sect->sh_size; 73 } 74 #endif /* CONFIG_PPC64_ELF_ABI_V1 */ 75 76 #ifdef CONFIG_PPC_BARRIER_NOSPEC 77 sect = find_section(hdr, sechdrs, "__spec_barrier_fixup"); 78 if (sect != NULL) 79 do_barrier_nospec_fixups_range(barrier_nospec_enabled, 80 (void *)sect->sh_addr, 81 (void *)sect->sh_addr + sect->sh_size); 82 #endif /* CONFIG_PPC_BARRIER_NOSPEC */ 83 84 sect = find_section(hdr, sechdrs, "__lwsync_fixup"); 85 if (sect != NULL) 86 do_lwsync_fixups(cur_cpu_spec->cpu_features, 87 (void *)sect->sh_addr, 88 (void *)sect->sh_addr + sect->sh_size); 89 90 return 0; 91 } 92 93 static struct execmem_info execmem_info __ro_after_init; 94 95 struct execmem_info __init *execmem_arch_setup(void) 96 { 97 pgprot_t prot = strict_module_rwx_enabled() ? PAGE_KERNEL : PAGE_KERNEL_EXEC; 98 unsigned long fallback_start = 0, fallback_end = 0; 99 unsigned long start, end; 100 101 /* 102 * BOOK3S_32 and 8xx define MODULES_VADDR for text allocations and 103 * allow allocating data in the entire vmalloc space 104 */ 105 #ifdef MODULES_VADDR 106 unsigned long limit = (unsigned long)_etext - SZ_32M; 107 108 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR); 109 110 /* First try within 32M limit from _etext to avoid branch trampolines */ 111 if (MODULES_VADDR < PAGE_OFFSET && MODULES_END > limit) { 112 start = limit; 113 fallback_start = MODULES_VADDR; 114 fallback_end = MODULES_END; 115 } else { 116 start = MODULES_VADDR; 117 } 118 119 end = MODULES_END; 120 #else 121 start = VMALLOC_START; 122 end = VMALLOC_END; 123 #endif 124 125 execmem_info = (struct execmem_info){ 126 .ranges = { 127 [EXECMEM_DEFAULT] = { 128 .start = start, 129 .end = end, 130 .pgprot = prot, 131 .alignment = 1, 132 .fallback_start = fallback_start, 133 .fallback_end = fallback_end, 134 }, 135 [EXECMEM_MODULE_DATA] = { 136 .start = VMALLOC_START, 137 .end = VMALLOC_END, 138 .pgprot = PAGE_KERNEL, 139 .alignment = 1, 140 }, 141 }, 142 }; 143 144 return &execmem_info; 145 } 146