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Commit | Line | Data |
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5234f5eb | 1 | /* |
835c34a1 | 2 | * handle transition of Linux booting another kernel |
5234f5eb EB |
3 | * Copyright (C) 2002-2005 Eric Biederman <ebiederm@xmission.com> |
4 | * | |
5 | * This source code is licensed under the GNU General Public License, | |
6 | * Version 2. See the file COPYING for more details. | |
7 | */ | |
8 | ||
12db5562 VG |
9 | #define pr_fmt(fmt) "kexec: " fmt |
10 | ||
5234f5eb EB |
11 | #include <linux/mm.h> |
12 | #include <linux/kexec.h> | |
5234f5eb | 13 | #include <linux/string.h> |
5a0e3ad6 | 14 | #include <linux/gfp.h> |
5234f5eb | 15 | #include <linux/reboot.h> |
fd59d231 | 16 | #include <linux/numa.h> |
f43fdad8 | 17 | #include <linux/ftrace.h> |
fef3a7a1 | 18 | #include <linux/io.h> |
fee7b0d8 | 19 | #include <linux/suspend.h> |
d6472302 | 20 | #include <linux/vmalloc.h> |
f43fdad8 | 21 | |
9ebdc79f | 22 | #include <asm/init.h> |
5234f5eb | 23 | #include <asm/pgtable.h> |
5234f5eb EB |
24 | #include <asm/tlbflush.h> |
25 | #include <asm/mmu_context.h> | |
8643e28d | 26 | #include <asm/io_apic.h> |
17f557e5 | 27 | #include <asm/debugreg.h> |
27f48d3e | 28 | #include <asm/kexec-bzimage64.h> |
4545c898 | 29 | #include <asm/setup.h> |
8bf27556 | 30 | |
74ca317c | 31 | #ifdef CONFIG_KEXEC_FILE |
cb105258 | 32 | static struct kexec_file_ops *kexec_file_loaders[] = { |
27f48d3e | 33 | &kexec_bzImage64_ops, |
cb105258 | 34 | }; |
74ca317c | 35 | #endif |
cb105258 | 36 | |
f5deb796 HY |
37 | static void free_transition_pgtable(struct kimage *image) |
38 | { | |
39 | free_page((unsigned long)image->arch.pud); | |
40 | free_page((unsigned long)image->arch.pmd); | |
41 | free_page((unsigned long)image->arch.pte); | |
42 | } | |
43 | ||
44 | static int init_transition_pgtable(struct kimage *image, pgd_t *pgd) | |
45 | { | |
46 | pud_t *pud; | |
47 | pmd_t *pmd; | |
48 | pte_t *pte; | |
49 | unsigned long vaddr, paddr; | |
50 | int result = -ENOMEM; | |
51 | ||
52 | vaddr = (unsigned long)relocate_kernel; | |
53 | paddr = __pa(page_address(image->control_code_page)+PAGE_SIZE); | |
54 | pgd += pgd_index(vaddr); | |
55 | if (!pgd_present(*pgd)) { | |
56 | pud = (pud_t *)get_zeroed_page(GFP_KERNEL); | |
57 | if (!pud) | |
58 | goto err; | |
59 | image->arch.pud = pud; | |
60 | set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE)); | |
61 | } | |
62 | pud = pud_offset(pgd, vaddr); | |
63 | if (!pud_present(*pud)) { | |
64 | pmd = (pmd_t *)get_zeroed_page(GFP_KERNEL); | |
65 | if (!pmd) | |
66 | goto err; | |
67 | image->arch.pmd = pmd; | |
68 | set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); | |
69 | } | |
70 | pmd = pmd_offset(pud, vaddr); | |
71 | if (!pmd_present(*pmd)) { | |
72 | pte = (pte_t *)get_zeroed_page(GFP_KERNEL); | |
73 | if (!pte) | |
74 | goto err; | |
75 | image->arch.pte = pte; | |
76 | set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE)); | |
77 | } | |
78 | pte = pte_offset_kernel(pmd, vaddr); | |
79 | set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL_EXEC)); | |
80 | return 0; | |
81 | err: | |
82 | free_transition_pgtable(image); | |
83 | return result; | |
84 | } | |
85 | ||
9ebdc79f YL |
86 | static void *alloc_pgt_page(void *data) |
87 | { | |
88 | struct kimage *image = (struct kimage *)data; | |
89 | struct page *page; | |
90 | void *p = NULL; | |
91 | ||
92 | page = kimage_alloc_control_pages(image, 0); | |
93 | if (page) { | |
94 | p = page_address(page); | |
95 | clear_page(p); | |
96 | } | |
97 | ||
98 | return p; | |
99 | } | |
100 | ||
5234f5eb EB |
101 | static int init_pgtable(struct kimage *image, unsigned long start_pgtable) |
102 | { | |
9ebdc79f YL |
103 | struct x86_mapping_info info = { |
104 | .alloc_pgt_page = alloc_pgt_page, | |
105 | .context = image, | |
106 | .pmd_flag = __PAGE_KERNEL_LARGE_EXEC, | |
107 | }; | |
084d1283 | 108 | unsigned long mstart, mend; |
8bf27556 | 109 | pgd_t *level4p; |
f5deb796 | 110 | int result; |
084d1283 YL |
111 | int i; |
112 | ||
8bf27556 | 113 | level4p = (pgd_t *)__va(start_pgtable); |
9ebdc79f | 114 | clear_page(level4p); |
0e691cf8 YL |
115 | for (i = 0; i < nr_pfn_mapped; i++) { |
116 | mstart = pfn_mapped[i].start << PAGE_SHIFT; | |
117 | mend = pfn_mapped[i].end << PAGE_SHIFT; | |
118 | ||
119 | result = kernel_ident_mapping_init(&info, | |
120 | level4p, mstart, mend); | |
121 | if (result) | |
122 | return result; | |
123 | } | |
084d1283 | 124 | |
53594547 | 125 | /* |
084d1283 YL |
126 | * segments's mem ranges could be outside 0 ~ max_pfn, |
127 | * for example when jump back to original kernel from kexeced kernel. | |
128 | * or first kernel is booted with user mem map, and second kernel | |
129 | * could be loaded out of that range. | |
53594547 | 130 | */ |
084d1283 YL |
131 | for (i = 0; i < image->nr_segments; i++) { |
132 | mstart = image->segment[i].mem; | |
133 | mend = mstart + image->segment[i].memsz; | |
134 | ||
9ebdc79f YL |
135 | result = kernel_ident_mapping_init(&info, |
136 | level4p, mstart, mend); | |
084d1283 YL |
137 | |
138 | if (result) | |
139 | return result; | |
140 | } | |
141 | ||
f5deb796 | 142 | return init_transition_pgtable(image, level4p); |
5234f5eb EB |
143 | } |
144 | ||
145 | static void set_idt(void *newidt, u16 limit) | |
146 | { | |
36c4fd23 | 147 | struct desc_ptr curidt; |
5234f5eb EB |
148 | |
149 | /* x86-64 supports unaliged loads & stores */ | |
36c4fd23 EB |
150 | curidt.size = limit; |
151 | curidt.address = (unsigned long)newidt; | |
5234f5eb EB |
152 | |
153 | __asm__ __volatile__ ( | |
36c4fd23 EB |
154 | "lidtq %0\n" |
155 | : : "m" (curidt) | |
5234f5eb EB |
156 | ); |
157 | }; | |
158 | ||
159 | ||
160 | static void set_gdt(void *newgdt, u16 limit) | |
161 | { | |
36c4fd23 | 162 | struct desc_ptr curgdt; |
5234f5eb EB |
163 | |
164 | /* x86-64 supports unaligned loads & stores */ | |
36c4fd23 EB |
165 | curgdt.size = limit; |
166 | curgdt.address = (unsigned long)newgdt; | |
5234f5eb EB |
167 | |
168 | __asm__ __volatile__ ( | |
36c4fd23 EB |
169 | "lgdtq %0\n" |
170 | : : "m" (curgdt) | |
5234f5eb EB |
171 | ); |
172 | }; | |
173 | ||
174 | static void load_segments(void) | |
175 | { | |
176 | __asm__ __volatile__ ( | |
36c4fd23 EB |
177 | "\tmovl %0,%%ds\n" |
178 | "\tmovl %0,%%es\n" | |
179 | "\tmovl %0,%%ss\n" | |
180 | "\tmovl %0,%%fs\n" | |
181 | "\tmovl %0,%%gs\n" | |
2ec5e3a8 | 182 | : : "a" (__KERNEL_DS) : "memory" |
5234f5eb | 183 | ); |
5234f5eb EB |
184 | } |
185 | ||
74ca317c | 186 | #ifdef CONFIG_KEXEC_FILE |
dd5f7260 VG |
187 | /* Update purgatory as needed after various image segments have been prepared */ |
188 | static int arch_update_purgatory(struct kimage *image) | |
189 | { | |
190 | int ret = 0; | |
191 | ||
192 | if (!image->file_mode) | |
193 | return 0; | |
194 | ||
195 | /* Setup copying of backup region */ | |
196 | if (image->type == KEXEC_TYPE_CRASH) { | |
40c50c1f TG |
197 | ret = kexec_purgatory_get_set_symbol(image, |
198 | "purgatory_backup_dest", | |
dd5f7260 VG |
199 | &image->arch.backup_load_addr, |
200 | sizeof(image->arch.backup_load_addr), 0); | |
201 | if (ret) | |
202 | return ret; | |
203 | ||
40c50c1f TG |
204 | ret = kexec_purgatory_get_set_symbol(image, |
205 | "purgatory_backup_src", | |
dd5f7260 VG |
206 | &image->arch.backup_src_start, |
207 | sizeof(image->arch.backup_src_start), 0); | |
208 | if (ret) | |
209 | return ret; | |
210 | ||
40c50c1f TG |
211 | ret = kexec_purgatory_get_set_symbol(image, |
212 | "purgatory_backup_sz", | |
dd5f7260 VG |
213 | &image->arch.backup_src_sz, |
214 | sizeof(image->arch.backup_src_sz), 0); | |
215 | if (ret) | |
216 | return ret; | |
217 | } | |
218 | ||
219 | return ret; | |
220 | } | |
74ca317c VG |
221 | #else /* !CONFIG_KEXEC_FILE */ |
222 | static inline int arch_update_purgatory(struct kimage *image) | |
223 | { | |
224 | return 0; | |
225 | } | |
226 | #endif /* CONFIG_KEXEC_FILE */ | |
dd5f7260 | 227 | |
5234f5eb EB |
228 | int machine_kexec_prepare(struct kimage *image) |
229 | { | |
4bfaaef0 | 230 | unsigned long start_pgtable; |
5234f5eb EB |
231 | int result; |
232 | ||
233 | /* Calculate the offsets */ | |
72414d3f | 234 | start_pgtable = page_to_pfn(image->control_code_page) << PAGE_SHIFT; |
5234f5eb EB |
235 | |
236 | /* Setup the identity mapped 64bit page table */ | |
237 | result = init_pgtable(image, start_pgtable); | |
72414d3f | 238 | if (result) |
5234f5eb | 239 | return result; |
5234f5eb | 240 | |
dd5f7260 VG |
241 | /* update purgatory as needed */ |
242 | result = arch_update_purgatory(image); | |
243 | if (result) | |
244 | return result; | |
245 | ||
5234f5eb EB |
246 | return 0; |
247 | } | |
248 | ||
249 | void machine_kexec_cleanup(struct kimage *image) | |
250 | { | |
f5deb796 | 251 | free_transition_pgtable(image); |
5234f5eb EB |
252 | } |
253 | ||
254 | /* | |
255 | * Do not allocate memory (or fail in any way) in machine_kexec(). | |
256 | * We are past the point of no return, committed to rebooting now. | |
257 | */ | |
3ab83521 | 258 | void machine_kexec(struct kimage *image) |
5234f5eb | 259 | { |
4bfaaef0 MD |
260 | unsigned long page_list[PAGES_NR]; |
261 | void *control_page; | |
fee7b0d8 | 262 | int save_ftrace_enabled; |
5234f5eb | 263 | |
fee7b0d8 | 264 | #ifdef CONFIG_KEXEC_JUMP |
6407df5c | 265 | if (image->preserve_context) |
fee7b0d8 HY |
266 | save_processor_state(); |
267 | #endif | |
268 | ||
269 | save_ftrace_enabled = __ftrace_enabled_save(); | |
f43fdad8 | 270 | |
5234f5eb EB |
271 | /* Interrupts aren't acceptable while we reboot */ |
272 | local_irq_disable(); | |
17f557e5 | 273 | hw_breakpoint_disable(); |
5234f5eb | 274 | |
fee7b0d8 HY |
275 | if (image->preserve_context) { |
276 | #ifdef CONFIG_X86_IO_APIC | |
277 | /* | |
278 | * We need to put APICs in legacy mode so that we can | |
279 | * get timer interrupts in second kernel. kexec/kdump | |
280 | * paths already have calls to disable_IO_APIC() in | |
281 | * one form or other. kexec jump path also need | |
282 | * one. | |
283 | */ | |
284 | disable_IO_APIC(); | |
285 | #endif | |
286 | } | |
287 | ||
4bfaaef0 | 288 | control_page = page_address(image->control_code_page) + PAGE_SIZE; |
fee7b0d8 | 289 | memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE); |
4bfaaef0 | 290 | |
e3ebadd9 | 291 | page_list[PA_CONTROL_PAGE] = virt_to_phys(control_page); |
fee7b0d8 | 292 | page_list[VA_CONTROL_PAGE] = (unsigned long)control_page; |
4bfaaef0 MD |
293 | page_list[PA_TABLE_PAGE] = |
294 | (unsigned long)__pa(page_address(image->control_code_page)); | |
5234f5eb | 295 | |
fee7b0d8 HY |
296 | if (image->type == KEXEC_TYPE_DEFAULT) |
297 | page_list[PA_SWAP_PAGE] = (page_to_pfn(image->swap_page) | |
298 | << PAGE_SHIFT); | |
299 | ||
fef3a7a1 HY |
300 | /* |
301 | * The segment registers are funny things, they have both a | |
2a8a3d5b EB |
302 | * visible and an invisible part. Whenever the visible part is |
303 | * set to a specific selector, the invisible part is loaded | |
304 | * with from a table in memory. At no other time is the | |
305 | * descriptor table in memory accessed. | |
5234f5eb EB |
306 | * |
307 | * I take advantage of this here by force loading the | |
308 | * segments, before I zap the gdt with an invalid value. | |
309 | */ | |
310 | load_segments(); | |
fef3a7a1 HY |
311 | /* |
312 | * The gdt & idt are now invalid. | |
5234f5eb EB |
313 | * If you want to load them you must set up your own idt & gdt. |
314 | */ | |
fef3a7a1 HY |
315 | set_gdt(phys_to_virt(0), 0); |
316 | set_idt(phys_to_virt(0), 0); | |
4bfaaef0 | 317 | |
5234f5eb | 318 | /* now call it */ |
fee7b0d8 HY |
319 | image->start = relocate_kernel((unsigned long)image->head, |
320 | (unsigned long)page_list, | |
321 | image->start, | |
322 | image->preserve_context); | |
323 | ||
324 | #ifdef CONFIG_KEXEC_JUMP | |
6407df5c | 325 | if (image->preserve_context) |
fee7b0d8 HY |
326 | restore_processor_state(); |
327 | #endif | |
328 | ||
329 | __ftrace_enabled_restore(save_ftrace_enabled); | |
5234f5eb | 330 | } |
2c8c0e6b | 331 | |
fd59d231 KO |
332 | void arch_crash_save_vmcoreinfo(void) |
333 | { | |
401721ec | 334 | VMCOREINFO_NUMBER(phys_base); |
69243f91 | 335 | VMCOREINFO_SYMBOL(init_level4_pgt); |
92df5c3e KO |
336 | |
337 | #ifdef CONFIG_NUMA | |
338 | VMCOREINFO_SYMBOL(node_data); | |
339 | VMCOREINFO_LENGTH(node_data, MAX_NUMNODES); | |
340 | #endif | |
b6085a86 | 341 | vmcoreinfo_append_str("KERNELOFFSET=%lx\n", |
4545c898 | 342 | kaslr_offset()); |
401721ec | 343 | VMCOREINFO_NUMBER(KERNEL_IMAGE_SIZE); |
fd59d231 KO |
344 | } |
345 | ||
cb105258 VG |
346 | /* arch-dependent functionality related to kexec file-based syscall */ |
347 | ||
74ca317c | 348 | #ifdef CONFIG_KEXEC_FILE |
cb105258 VG |
349 | int arch_kexec_kernel_image_probe(struct kimage *image, void *buf, |
350 | unsigned long buf_len) | |
351 | { | |
352 | int i, ret = -ENOEXEC; | |
353 | struct kexec_file_ops *fops; | |
354 | ||
355 | for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) { | |
356 | fops = kexec_file_loaders[i]; | |
357 | if (!fops || !fops->probe) | |
358 | continue; | |
359 | ||
360 | ret = fops->probe(buf, buf_len); | |
361 | if (!ret) { | |
362 | image->fops = fops; | |
363 | return ret; | |
364 | } | |
365 | } | |
366 | ||
367 | return ret; | |
368 | } | |
369 | ||
370 | void *arch_kexec_kernel_image_load(struct kimage *image) | |
371 | { | |
dd5f7260 VG |
372 | vfree(image->arch.elf_headers); |
373 | image->arch.elf_headers = NULL; | |
374 | ||
cb105258 VG |
375 | if (!image->fops || !image->fops->load) |
376 | return ERR_PTR(-ENOEXEC); | |
377 | ||
378 | return image->fops->load(image, image->kernel_buf, | |
379 | image->kernel_buf_len, image->initrd_buf, | |
380 | image->initrd_buf_len, image->cmdline_buf, | |
381 | image->cmdline_buf_len); | |
382 | } | |
383 | ||
384 | int arch_kimage_file_post_load_cleanup(struct kimage *image) | |
385 | { | |
386 | if (!image->fops || !image->fops->cleanup) | |
387 | return 0; | |
388 | ||
27f48d3e | 389 | return image->fops->cleanup(image->image_loader_data); |
cb105258 | 390 | } |
12db5562 | 391 | |
978e30c9 | 392 | #ifdef CONFIG_KEXEC_VERIFY_SIG |
8e7d8381 VG |
393 | int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel, |
394 | unsigned long kernel_len) | |
395 | { | |
396 | if (!image->fops || !image->fops->verify_sig) { | |
397 | pr_debug("kernel loader does not support signature verification."); | |
398 | return -EKEYREJECTED; | |
399 | } | |
400 | ||
401 | return image->fops->verify_sig(kernel, kernel_len); | |
402 | } | |
978e30c9 | 403 | #endif |
8e7d8381 | 404 | |
12db5562 VG |
405 | /* |
406 | * Apply purgatory relocations. | |
407 | * | |
408 | * ehdr: Pointer to elf headers | |
409 | * sechdrs: Pointer to section headers. | |
410 | * relsec: section index of SHT_RELA section. | |
411 | * | |
412 | * TODO: Some of the code belongs to generic code. Move that in kexec.c. | |
413 | */ | |
414 | int arch_kexec_apply_relocations_add(const Elf64_Ehdr *ehdr, | |
415 | Elf64_Shdr *sechdrs, unsigned int relsec) | |
416 | { | |
417 | unsigned int i; | |
418 | Elf64_Rela *rel; | |
419 | Elf64_Sym *sym; | |
420 | void *location; | |
421 | Elf64_Shdr *section, *symtabsec; | |
422 | unsigned long address, sec_base, value; | |
423 | const char *strtab, *name, *shstrtab; | |
424 | ||
425 | /* | |
426 | * ->sh_offset has been modified to keep the pointer to section | |
427 | * contents in memory | |
428 | */ | |
429 | rel = (void *)sechdrs[relsec].sh_offset; | |
430 | ||
431 | /* Section to which relocations apply */ | |
432 | section = &sechdrs[sechdrs[relsec].sh_info]; | |
433 | ||
434 | pr_debug("Applying relocate section %u to %u\n", relsec, | |
435 | sechdrs[relsec].sh_info); | |
436 | ||
437 | /* Associated symbol table */ | |
438 | symtabsec = &sechdrs[sechdrs[relsec].sh_link]; | |
439 | ||
440 | /* String table */ | |
441 | if (symtabsec->sh_link >= ehdr->e_shnum) { | |
442 | /* Invalid strtab section number */ | |
443 | pr_err("Invalid string table section index %d\n", | |
444 | symtabsec->sh_link); | |
445 | return -ENOEXEC; | |
446 | } | |
447 | ||
448 | strtab = (char *)sechdrs[symtabsec->sh_link].sh_offset; | |
449 | ||
450 | /* section header string table */ | |
451 | shstrtab = (char *)sechdrs[ehdr->e_shstrndx].sh_offset; | |
452 | ||
453 | for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) { | |
454 | ||
455 | /* | |
456 | * rel[i].r_offset contains byte offset from beginning | |
457 | * of section to the storage unit affected. | |
458 | * | |
459 | * This is location to update (->sh_offset). This is temporary | |
460 | * buffer where section is currently loaded. This will finally | |
461 | * be loaded to a different address later, pointed to by | |
462 | * ->sh_addr. kexec takes care of moving it | |
463 | * (kexec_load_segment()). | |
464 | */ | |
465 | location = (void *)(section->sh_offset + rel[i].r_offset); | |
466 | ||
467 | /* Final address of the location */ | |
468 | address = section->sh_addr + rel[i].r_offset; | |
469 | ||
470 | /* | |
471 | * rel[i].r_info contains information about symbol table index | |
472 | * w.r.t which relocation must be made and type of relocation | |
473 | * to apply. ELF64_R_SYM() and ELF64_R_TYPE() macros get | |
474 | * these respectively. | |
475 | */ | |
476 | sym = (Elf64_Sym *)symtabsec->sh_offset + | |
477 | ELF64_R_SYM(rel[i].r_info); | |
478 | ||
479 | if (sym->st_name) | |
480 | name = strtab + sym->st_name; | |
481 | else | |
482 | name = shstrtab + sechdrs[sym->st_shndx].sh_name; | |
483 | ||
484 | pr_debug("Symbol: %s info: %02x shndx: %02x value=%llx size: %llx\n", | |
485 | name, sym->st_info, sym->st_shndx, sym->st_value, | |
486 | sym->st_size); | |
487 | ||
488 | if (sym->st_shndx == SHN_UNDEF) { | |
489 | pr_err("Undefined symbol: %s\n", name); | |
490 | return -ENOEXEC; | |
491 | } | |
492 | ||
493 | if (sym->st_shndx == SHN_COMMON) { | |
494 | pr_err("symbol '%s' in common section\n", name); | |
495 | return -ENOEXEC; | |
496 | } | |
497 | ||
498 | if (sym->st_shndx == SHN_ABS) | |
499 | sec_base = 0; | |
500 | else if (sym->st_shndx >= ehdr->e_shnum) { | |
501 | pr_err("Invalid section %d for symbol %s\n", | |
502 | sym->st_shndx, name); | |
503 | return -ENOEXEC; | |
504 | } else | |
505 | sec_base = sechdrs[sym->st_shndx].sh_addr; | |
506 | ||
507 | value = sym->st_value; | |
508 | value += sec_base; | |
509 | value += rel[i].r_addend; | |
510 | ||
511 | switch (ELF64_R_TYPE(rel[i].r_info)) { | |
512 | case R_X86_64_NONE: | |
513 | break; | |
514 | case R_X86_64_64: | |
515 | *(u64 *)location = value; | |
516 | break; | |
517 | case R_X86_64_32: | |
518 | *(u32 *)location = value; | |
519 | if (value != *(u32 *)location) | |
520 | goto overflow; | |
521 | break; | |
522 | case R_X86_64_32S: | |
523 | *(s32 *)location = value; | |
524 | if ((s64)value != *(s32 *)location) | |
525 | goto overflow; | |
526 | break; | |
527 | case R_X86_64_PC32: | |
528 | value -= (u64)address; | |
529 | *(u32 *)location = value; | |
530 | break; | |
531 | default: | |
532 | pr_err("Unknown rela relocation: %llu\n", | |
533 | ELF64_R_TYPE(rel[i].r_info)); | |
534 | return -ENOEXEC; | |
535 | } | |
536 | } | |
537 | return 0; | |
538 | ||
539 | overflow: | |
540 | pr_err("Overflow in relocation type %d value 0x%lx\n", | |
541 | (int)ELF64_R_TYPE(rel[i].r_info), value); | |
542 | return -ENOEXEC; | |
543 | } | |
74ca317c | 544 | #endif /* CONFIG_KEXEC_FILE */ |
1e5768ae XP |
545 | |
546 | static int | |
547 | kexec_mark_range(unsigned long start, unsigned long end, bool protect) | |
548 | { | |
549 | struct page *page; | |
550 | unsigned int nr_pages; | |
551 | ||
552 | /* | |
553 | * For physical range: [start, end]. We must skip the unassigned | |
554 | * crashk resource with zero-valued "end" member. | |
555 | */ | |
556 | if (!end || start > end) | |
557 | return 0; | |
558 | ||
559 | page = pfn_to_page(start >> PAGE_SHIFT); | |
560 | nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; | |
561 | if (protect) | |
562 | return set_pages_ro(page, nr_pages); | |
563 | else | |
564 | return set_pages_rw(page, nr_pages); | |
565 | } | |
566 | ||
567 | static void kexec_mark_crashkres(bool protect) | |
568 | { | |
569 | unsigned long control; | |
570 | ||
571 | kexec_mark_range(crashk_low_res.start, crashk_low_res.end, protect); | |
572 | ||
573 | /* Don't touch the control code page used in crash_kexec().*/ | |
574 | control = PFN_PHYS(page_to_pfn(kexec_crash_image->control_code_page)); | |
575 | /* Control code page is located in the 2nd page. */ | |
576 | kexec_mark_range(crashk_res.start, control + PAGE_SIZE - 1, protect); | |
577 | control += KEXEC_CONTROL_PAGE_SIZE; | |
578 | kexec_mark_range(control, crashk_res.end, protect); | |
579 | } | |
580 | ||
581 | void arch_kexec_protect_crashkres(void) | |
582 | { | |
583 | kexec_mark_crashkres(true); | |
584 | } | |
585 | ||
586 | void arch_kexec_unprotect_crashkres(void) | |
587 | { | |
588 | kexec_mark_crashkres(false); | |
589 | } |